Ruataniwha Water Storage Scheme PART C Assessment of Environmental Effects May 2013
Ruataniwha Water Storage Scheme PART C
Assessment of Environmental Effects
May 2013
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Table of Contents
PREAMBLE ......................................................................................................................... 1
1 INTRODUCTION ...................................................................................................... 5
1.1 Scheme History Summary .......................................................................................................... 5
1.2 Ruataniwha – A Nationally Significant Scheme .......................................................................... 6
1.3 Resource Consent Applications, Notice of Requirement and Proposed Conditions ................. 8
1.3.1 District and Regional Consents....................................................................................... 8
1.3.2 Notice of Requirement ................................................................................................... 9
1.3.3 Proposed Conditions ....................................................................................................10
1.4 Management Plan Approach....................................................................................................10
1.5 Integrated Assessment of Environmental Effects ....................................................................12
1.6 HBRIC Ltd ..................................................................................................................................12
1.7 AEE Report Structure................................................................................................................13
1.8 Studies Undertaken ..................................................................................................................14
1.9 External Peer Reviews ..............................................................................................................17
1.10 Proposed Conditions ................................................................................................................18
2 SCHEME DEVELOPMENT PROCESS ......................................................................... 20
2.1 Identification of Scheme Potential ...........................................................................................20
2.2 Pre-Feasibility Studies ..............................................................................................................20
2.3 Feasibility Study........................................................................................................................21
2.4 Alternatives Assessment - Scheme Refinement .......................................................................22
2.5 Smaller Off-river Storage Sites versus In-river Dam Approach ................................................22
2.6 On-farm Storage Schemes........................................................................................................24
2.7 Primary Distribution System – Zones A to D ............................................................................26
2.8 Liaison with Regulatory Authorities .........................................................................................27
2.9 Consultation Summary .............................................................................................................28
3 TUKITUKI CATCHMENT AND THE EXISTING ENVIRONMENT ................................... 29
3.1 Introduction .............................................................................................................................29
3.2 Location and Area Reference Information and Terminology ...................................................29
3.3 Geological Features ..................................................................................................................31
3.4 Surface Water Resources .........................................................................................................33
3.5 Groundwater Resources ...........................................................................................................35
3.5.1 The Ruataniwha Basin and Aquifer ..............................................................................35
3.5.2 The Otane Basin and Aquifer .......................................................................................36
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3.5.3 The Lower Tukituki Aquifer System .............................................................................36
3.6 Values .......................................................................................................................................36
3.6.1 Cultural Values .............................................................................................................37
3.6.2 Social Values .................................................................................................................38
3.6.3 Economic Values ..........................................................................................................38
3.6.4 Ecological Values ..........................................................................................................38
3.6.5 Landscape Values .........................................................................................................39
3.7 Current Use ..............................................................................................................................39
3.8 Urban Development .................................................................................................................40
3.8.1 Central Hawke’s Bay District ........................................................................................40
3.8.2 Hastings District............................................................................................................41
3.9 Social Environment and Community Profile ............................................................................41
3.9.1 Central Hawke’s Bay District ........................................................................................41
3.9.2 Hastings District............................................................................................................42
3.10 Terrestrial Ecology and Vegetation ..........................................................................................42
3.11 Landscape .................................................................................................................................43
3.12 Noise Environment ...................................................................................................................43
3.13 Traffic Environment ..................................................................................................................44
3.14 Air Environment .......................................................................................................................44
3.15 Climate Change ........................................................................................................................45
4 PROJECT DESCRIPTION SUMMARY ........................................................................ 48
4.1 Project Description Document .................................................................................................48
4.2 Scheme Overview .....................................................................................................................48
4.3 Dam Design ..............................................................................................................................49
4.4 Reservoir Operating Regime ....................................................................................................50
4.5 Water Distribution System .......................................................................................................51
4.6 Hydroelectric Power Generation .............................................................................................53
4.7 Scheme Construction & Commissioning ..................................................................................54
4.8 Scheme Operation & Maintenance ..........................................................................................55
4.9 Potential Impacts from Operation ...........................................................................................55
5 ZONE M HEADRACE CONCEPT ............................................................................... 56
6 ENVIRONMENTAL FLOW OPTIMISATION ............................................................... 58
6.1 Introduction and Basis for Assessment ....................................................................................58
6.2 Assessment Undertaken ..........................................................................................................58
6.3 Results of Assessment ..............................................................................................................60
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6.3.1 Flushing Flows ..............................................................................................................60
6.3.2 Effects on Downstream Low Flows and Low Flow Supplementation ..........................61
6.4 Report Recommendations .......................................................................................................62
7 IRRIGATION ENVIRONMENTAL MANAGEMENT PLAN ............................................ 65
8 INTEGRATED MITIGATION AND OFFSET APPROACH .............................................. 68
9 RMA ACT FRAMEWORK ........................................................................................ 72
9.1 Introduction .............................................................................................................................72
9.2 District Councils ........................................................................................................................72
9.2.1 RMA Status of Activities within the Central Hawke’s Bay District ...............................72
9.2.2 RMA Status of Activities within the Hastings District ..................................................75
9.3 Hawke’s Bay Regional Council ..................................................................................................76
9.3.1 RMA Status of Activities within the Hawke’s Bay Region ............................................76
9.4 Department of Conservation ...................................................................................................80
9.5 Consenting Approach ...............................................................................................................80
9.5.1 District Council Jurisdiction ..........................................................................................81
9.5.2 Regional Council Jurisdiction ........................................................................................81
9.6 Term of Consents and Lapse Periods .......................................................................................85
9.7 Applications to be made at a Later Date ..................................................................................86
9.8 Other Matters to be addressed at a Later Date .......................................................................88
9.9 Policy Context ...........................................................................................................................88
9.9.1 National Policy Statements ..........................................................................................90
9.9.2 National Environmental Standards / Regulations ........................................................90
9.9.3 Regional Policy and Planning Documents ....................................................................91
9.9.4 District Plans .................................................................................................................93
9.10 Statutory Assessment of Notice of Requirement.....................................................................94
9.11 Part 2 of the RMA .....................................................................................................................96
10 INTRODUCTION TO MODELLING ASSESSMENTS .................................................... 98
11 GROUND / SURFACE WATER FLOWS – SCENARIO MODELLING .............................. 99
11.1 Scenarios Modelled ..................................................................................................................99
11.2 Effects on the Aquifer System ................................................................................................100
11.3 Effects on River Flows ............................................................................................................102
12 TUKITUKI RIVER NUTRIENT MODELLING .............................................................. 105
12.1 Introduction ...........................................................................................................................105
12.2 OVERSEER® Nutrient Budget’s Modelling ..............................................................................105
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12.3 Stream Modelling (TRIM2 Calibration) ..................................................................................105
12.4 Stream Modelling (TRIM2 Scenario Modelling) .....................................................................106
13 GROUNDWATER – DRINKING WATER MODELLING .............................................. 111
14 EFFECTS ASSESSMENT METHODOLOGY ............................................................... 113
14.1 Assessment Methodology ......................................................................................................113
14.1.1 Water Quality Assessments .......................................................................................113
14.1.2 Ecology Assessments ..................................................................................................113
14.1.3 Cultural Social and Recreational Assessment Reports ...............................................113
14.1.4 Construction, Landscape and Operations Assessment Reports .................................113
14.1.5 Economic Assessment Reports ..................................................................................113
15 EFFECTS OF RESERVOIR WATER QUALITY ON RECEIVING WATERS ....................... 115
15.1 Potential Environmental Effects .............................................................................................115
15.2 Assessments Undertaken .......................................................................................................115
15.3 Results of Assessment ............................................................................................................117
15.4 Suggested Approach for Effects Identified .............................................................................118
16 AQUATIC ECOLOGY ............................................................................................. 120
16.1 Potential Environmental Effects .............................................................................................120
16.2 Assessments Undertaken .......................................................................................................121
16.3 Results of Assessments ..........................................................................................................121
16.4 Suggested Approach for Effects Identified .............................................................................127
17 TERRESTRIAL ECOLOGY ....................................................................................... 130
17.1 Potential Environmental Effects .............................................................................................130
17.2 Assessments Undertaken .......................................................................................................130
17.3 Results of Assessment ............................................................................................................131
17.4 Suggested Approach for Effects Identified. ............................................................................132
18 CULTURAL IMPACT ASSESSMENT ........................................................................ 135
18.1 Introduction ...........................................................................................................................135
18.2 Involvement of Mana Whenua ..............................................................................................135
18.3 First CIA Report – Overarching Issues ....................................................................................136
18.4 Supplementary CIA Report .....................................................................................................136
18.5 Lower Tukituki (Heretaunga) Specific Issues ..........................................................................137
18.6 Zone M Addendum Report .....................................................................................................138
19 SOCIAL IMPACT ASSESSMENT ............................................................................. 140
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19.1 Potential Environmental Effects .............................................................................................140
19.2 Assessments Undertaken .......................................................................................................140
19.3 Results of Assessment ............................................................................................................141
19.4 Suggested Approach for Effects Identified .............................................................................142
20 RECREATION ASSESSMENT ................................................................................. 144
20.1 Potential Environmental Effects .............................................................................................144
20.2 Assessments Undertaken .......................................................................................................145
20.3 Results of Assessment ............................................................................................................146
20.4 Suggested Approach for Effects Identified .............................................................................146
21 ROAD INFRASTRUCTURE AND TRAFFIC ................................................................ 148
21.1 Potential Environmental Effects .............................................................................................148
21.2 Assessments Undertaken .......................................................................................................148
21.3 Results of Assessment ............................................................................................................148
21.3.1 Bridge Infrastructure ..................................................................................................148
21.3.2 Road Pavement and Surfacing ...................................................................................149
21.3.3 Road Alignment ..........................................................................................................149
21.3.4 New Access Roads ......................................................................................................149
21.3.5 Beach Nourishment Operation ..................................................................................150
21.4 Suggested Approach for Effects Identified .............................................................................150
22 NOISE EFFECTS .................................................................................................... 153
22.1 Potential Environmental Effects .............................................................................................153
22.2 Assessment Undertaken ........................................................................................................153
22.3 Results of Assessment ............................................................................................................153
22.4 Suggested Approach for Effects Identified .............................................................................154
23 REGIONAL ECONOMICS ...................................................................................... 155
23.1 Potential Effects .....................................................................................................................155
23.2 Assessments Undertaken .......................................................................................................155
23.3 Results of Assessment ............................................................................................................156
23.3.1 Economic Benefits ......................................................................................................156
23.3.2 Economic Impacts ......................................................................................................159
24 ARCHAEOLOGICAL ASSESSMENT ......................................................................... 164
24.1 Potential Environmental Effects .............................................................................................164
24.2 Assessment Undertaken ........................................................................................................164
24.3 Result of Assessment .............................................................................................................165
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24.4 Suggested Approach for Effects Identified .............................................................................165
25 LANDSCAPE AND VISUAL EFFECTS ....................................................................... 168
25.1 Potential Environmental Effects .............................................................................................168
25.2 Assessments Undertaken .......................................................................................................169
25.3 Results of Assessment ............................................................................................................170
25.4 Suggested Approach for Effects Identified .............................................................................172
26 SEDIMENTATION EFFECTS ................................................................................... 174
26.1 Potential Environmental Effects .............................................................................................174
26.2 Assessments Undertaken .......................................................................................................174
26.3 Results of Assessment ............................................................................................................175
26.4 Suggested Approach for Effects Identified .............................................................................176
27 DAM BREAK STUDY ............................................................................................ 180
27.1 Potential Environmental Effects .............................................................................................180
27.2 Assessments Undertaken .......................................................................................................180
27.3 Results of Assessment ............................................................................................................181
27.4 Suggested Approach for Effects Identified .............................................................................182
28 COMMUNITY ENGAGEMENT ............................................................................... 183
28.1 Introduction ...........................................................................................................................183
28.2 Leadership Group ...................................................................................................................183
28.3 Ruataniwha Stakeholder Group .............................................................................................184
28.4 Landowners in Main Scheme Infrastructure Areas ................................................................190
28.5 Land Use Intensification Working Party .................................................................................191
28.6 Mana Whenua ........................................................................................................................193
28.7 Pan Sector Group ...................................................................................................................197
28.8 Key Farmer Reference Group .................................................................................................198
28.9 Hawke’s Bay District Health Board .........................................................................................198
28.10 Outcomes of Consultation .....................................................................................................200
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PREAMBLE Hawke’s Bay Regional Investment Company Limited (HBRIC Ltd) seeks resource consents and
confirmation of a notice of requirement to enable it to build and operate a 90 million cubic metre
storage reservoir and associated intakes, canals, pipelines and outfalls together providing a water
distribution network. The dam and reservoir will be located in the upper Makaroro River in Central
Hawke’s Bay where it will harvest winter and other high flows and provide the storage capacity to
supply water at a high level of reliability for irrigation to between 25,000 and 30,000 hectares of
rural land.
The reservoir will also provide an important resource to maintain higher flows from the Makaroro
River contributing to the Tukituki River system at times when flows are most under stress and assist
the management of excess periphyton that currently diminishes recreational amenity in the lower
river. The Scheme includes a small (6.5MW) renewable energy hydro-electric power station to be
constructed adjacent to the dam.
The assets and operations for which resource consents and notice of requirement are sought in this
Application and Assessment of Effects are collectively referred to as the Ruataniwha Water Storage
Scheme (RWSS or the Scheme).
The Tukituki Catchment Proposal
The Ministers for the Environment and of Conservation are being requested to refer two matters to
be considered by a single Board of Inquiry being the RWSS resource consents and designation
package and Proposed Plan Change 6 (Change 6). These matters are collectively termed “The
Tukituki Catchment Proposal”. The Scheme is a cornerstone of the integrated management strategy
developed and adopted by the Hawke’s Bay Regional Council (HBRC) which has assessed1 the key
land and water management issues in the Tukituki Catchment as:
• Excessive growths of algae and slime, particularly in the Lower Tukituki River which are
impacting on swimming, fishing and other amenity values
• Inadequate physical habitat and habitat quality at times of low flow for the regionally
significant trout fishery and native fish
• Demand for more water for irrigation particularly in the Ruataniwha Plains areas.
Factors considered to be contributing to these issues have included:
• Existing minimum flows set too low 1 See s32 Evaluation Summary Report on Change 6 approved and adopted by the Council on 24 April 2013
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• Too much water authorised to be taken from rivers and groundwater
• Existing wastewater discharges from the Waipukurau and Waipawa oxidation ponds
degrading water quality, particularly with regard to phosphorus
• Stock in waterways.
HBRC’s studies supporting Change 6 have shown that the Ruataniwha Basin is characterised by a high
level of interaction between the groundwater and surface water. While the contribution of surface
water to groundwater through river bed losses is small, the contribution that groundwater makes to
the river flow at the eastern side of the basin is large. Pumping groundwater from the basin affects
the contribution groundwater makes to the river flows so it is important to manage the allocation of
groundwater holistically with the management of the surface water resource.
Land use activities drive demand for water for consumptive purposes such as urban and industrial
water supplies and for irrigation. Recent droughts, most recently in the summer of 2012-13, have
underscored the susceptibility of agricultural production to drought and the demand for a reliable
water supply, as well as the susceptibility of the Tukituki River environment which is under
considerable stress during prolonged droughts which are prevalent in Hawke’s Bay.
Climate change predictions of an increased frequency and severity of droughts in the future are only
likely to increase that demand. Land use activities can also influence the quality of both the surface
water and any underlying groundwater resource. Managing the effects of land uses therefore needs
to be integrated with the management of groundwater and surface water resources.
Arising from its analysis of catchment issues and the inter-relationship of groundwater and surface
water, HBRC developed a Tukituki Water Strategy which is summarised in the following table:
Resilient Ecosystems How do we get there:
Resilient Economy How do we get there:
Resilient communities How do we get there:
Harvest winter flows for summer use as a replacement to surface and groundwater takes
Storage based Community Irrigation Scheme
Flow on effects from business certainty and security
Review minimum flow and allocation limits and set water quality limits or targets
Plan provides allocation framework (water quantity and quality)
Flow on effects from water allocation framework
Support CHBDC to meet wastewater upgrade requirements in the current consent
Land and riparian management to minimise sediment and nutrient inputs to rivers
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The key mechanisms for implementing the elements of the Tukituki Water Strategy are Change 6 to
the RRMP, and the RWSS.
In order to deliver the Tukituki Water Strategy, HBRC recognised that the traditional planning
processes that were available to it for Change 6 and the RWSS would not provide the level of
integrated decision-making, certainty and timeliness of the decisions necessary for such a significant
strategic response to a resource management issue.
The HBRC therefore took an integrated approach in which it was proposed that the HBRIC Ltd
applications for resource consents for RWSS and HBRC’s own Change 6 would be considered
contemporaneously by a Board of Inquiry as a Proposal of National Significance. Preceding this
application, during 2012, there had been an extensive public consultation process using a document
entitled “Tukituki Choices” which established and discussed with the community and stakeholders
the options available for environmental management of the catchment both with, and without
storage, and the consequential effects of each option.
Change 6 provides for the implementation of allocation limits on surface and groundwater takes
while enabling community irrigation schemes in the Tukituki Catchment such as the RWSS, provided
freshwater objectives are met. The storage schemes are enabled in that any application for taking
water outside allocation limits can be made as a discretionary activity.
Main areas in which consents are sought
The consents which are the subject of this application are sought in four key areas
• Construction, operation and maintenance of dam and related structures
• Construction, operation and maintenance of upstream and downstream water intakes and
diversions
• Construction, operation and maintenance of downstream outfall structures and discharges
• Mitigation and offset work, including planting and beach nourishment.
The accompanying notice of requirement enables construction, operation and maintenance of the
primary water distribution network, and there are related resource consent applications within the
HBRC jurisdiction.
Key Scheme Benefits
As a community storage scheme, the RWSS enables a range of benefits to be achieved across the full
spectrum of ecological, economic and social values. The key benefits are considered to be:
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• The delivery of a summer river flow regime supporting ecological values and maintenance of
biodiversity in the river system
• Capacity for flushing flows each year to maintain natural flow variability and to help remove
excess periphyton growths and contribute to managing the public health risks associated
with cyanobacterial growth in the Makaroro, Waipawa and Lower Tukituki Rivers
• An attractive option for landowners with existing groundwater bores and surface takes to
access an alternative water supply and thereby assist them to adjust to proposed revised
minimum river flows in Change 6 without excessive disruption and enabling spring-fed rivers
and streams to be replenished
• Greater ability to introduce and enforce farm management plans for all landowners receiving
water from the Scheme, specifying (inter alia) nutrient discharge limits, implementation of
on-farm best management practices, protection of groundwater bores used for drinking
water, and the avoidance of stock damage to water bodies, wetlands and margins
• Regional GDP will increase by a one-off $1.1 billion mainly over the first four years as Scheme
construction and new farm investment occurs. As farms convert over time to Scheme
irrigation and increase production from changing land uses, economic analysis suggests the
regional GDP will benefit from an estimated additional $235 million per year and 2,250 full-
time equivalent jobs will be created from farm and farm support, and potential downstream
processing and processing support
• The construction of a 6.5MW renewable energy hydro-electricity generation resource
• Improvement in habitat for taonga species including longfin eel, koaro and bluegill bully over
the summer months, and the progressive return to natural flows (as groundwater
abstraction ramps down) of wetlands and waipuna.
Application Suite
The RWSS Application documents comprise the following:
RWSS Application Suite Section Component Reference
Part A Resource Consent Applications HBRIC (May 2013a)
Part B Notice of Requirement HBRIC (May 2013b)
Part C Assessment of Environmental Effects HBRIC (May 2013c)
Part D Proposed Conditions HBRIC (May 2013d)
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1 INTRODUCTION
1.1 Scheme History Summary
The Tukituki River is one of the Hawke’s Bay Region’s largest catchments with headwaters in the
Ruahine Ranges and covering 2,500 square kilometres. Six rivers and a number of streams cross the
Ruataniwha Plains merging into the Waipawa and Tukituki Rivers west of the Waipawa and
Waipukurau townships. East of the townships, the Waipawa River joins the Tukituki River and flows
north to enter Hawke Bay at Haumoana.
Apart from some areas of exotic forestry and the native vegetation in Ruahine Forest Park, the
catchment is largely deforested. Land use in the hill country is predominantly dry stock farming with
more intensive farming on the plains.
Beneath the Ruataniwha Plains, a complex system of gravels, silts and clays contain water from
rainfall and rivers. Some of the water leaves the Ruataniwha Basin through springs, joining the
Tukituki and Waipawa Rivers through their river beds.
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The lower Tukituki River is part of the iconic landscape of Te Mata Peak and the Kahuranaki Range.
The river is appreciated for its aesthetic, recreational and cultural values and, along with the aquifers
described in Section 3, is valued for the water it provides for household, stock and public supply,
commercial use and irrigation.
On-going droughts, drawing water for irrigation, and wastewater discharges have all had a negative
impact on the river. 153 water take consents in the Tukituki catchment are all due for renewal
between 2013 and 2015 and it is clear that many of these cannot be sustained at current levels. The
regional community including environment interest groups have expressed continuing concern since
2003 about the minimum flow levels in the Tukituki River, in addition to algal blooms with potential
effects on fish and other river life.
Addressing many of the issues identified in the catchment will tend to have flow-on adverse
consequences for one or more group of stakeholders. For example, increasing the minimum flows in
the river will affect the security of supply for irrigators. As well as developing a land and water
management strategy, and utilising regulatory processes to set minimum new flow limits, HBRC has
investigated the establishment of water storage schemes capable of harvesting river water in the
winter and during periods of high flows, in order to provide a source of irrigation water and a means
to supplement low flows during the summer. The Tukituki Catchment Proposal comprising Change 6
and the RWSS represents the culmination of this initiative.
1.2 Ruataniwha – A Nationally Significant Scheme
On the recommendation of the Environmental Protection Authority (EPA) the Minister for the
Environment and the Minister of Conservation2 may make a direction under the Resource
Management Act 1991 (RMA) for a matter to be referred to a Board of Inquiry or the Environment
Court for a decision, but may only do so if the matter is, or is part of, a proposal of national
significance3.
The RMA describes certain factors4 that may be relevant to whether a matter is, or is part of, a
proposal of national significance. These include (inter alia) whether the matter:
• Involves or is likely to involve significant use of natural and physical resources; or
2 The Minister of Conservation has a role under section 148(2) because one application forming part of the RWSS suite of resource consents (HBRC Consent CD120400D) involves deposition of sediment in the coastal marine area as a mitigation measure. 3 See section 147 4 See section 142 (3)
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• Involves or is likely to involve technology, processes or methods that are new to New
Zealand and that may affect its environment; or
• Affects or is likely to affect more than one region or district.
This section considers how these criteria might apply in the context of the RWSS.
The Land and Water Forum has described5 water as:
“…important to everyone in New Zealand because it provides great opportunities for all of us
– for our ecologies and environments, our farms and our cities, for recreation and for tourists,
as well as for energy production and industry. It is a source of life and food, and it is a central
part of our identity, particularly for iwi.
We all know that we need to manage it better for all of its multiple uses and values. We also
know that the health of our water bodies depends on what we do on the land. We share
responsibility as city dwellers and farmers, as domestic and industrial users, as foresters,
horticulturalists and energy generators, as tangata tiaki – in short, as New Zealanders”.
Around 68% of New Zealand’s national water allocation is supplied by groundwater with another
29% of the resource derived from surface water. Only around 3% of water is sourced from storage
reservoirs, mostly for urban supply6.
The RWSS has the capability to make a material impact on the growth of water storage infrastructure
in the New Zealand economy. With storage capability of 90 million cubic metres the Scheme will
easily be the largest reservoir for irrigation purposes in New Zealand, the next biggest being the
Opuha Dam in South Canterbury which stores 72 million cubic metres and supplies irrigation water
to an estimated 16,000 hectares.
Additionally the Scheme will provide enhanced minimum flows during dry summers to help support
ecological systems and flushing flows to help manage nuisance periphyton growth in summer.
The Scheme will involve the construction of an on-river dam on the Makaroro River in order to
harness winter and high river flows. The Application Design proposes an 83m high structure. The
crest of the dam will be 505m across the valley and the Makaroro River will be inundated for
approximately seven kilometres upstream of the dam. In relation to the criteria of national
significance this is considered to be a significant use of natural and physical resources.
5 Second Report of the Land and water Forum - April 2012 6 Update of Water Allocation Data and Estimate of Actual Water Use of Consented Takes 2009–10 Aqualinc Research Ltd
Prepared for Ministry for the Environment (Report No H10002/3, October 2010)
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New Zealand is one of the most water-rich countries in the world and one of only a few net food
exporters. But there is evidence that available surface and groundwater is already over-allocated
within a significant part of the country. This pressure on traditional sources arises as a result of
growth in more water-intensive agricultural uses (dairying and cropping) and climate change. The
capturing, storage and use of surplus water that would otherwise flow out to sea, such as is
proposed by the RWSS, is considered to be an excellent means by which New Zealand can improve
its agricultural output and contribute to the social and economic wellbeing of the Hawke’s Bay
community without exacerbating over-allocation issues.
The concept of creating winter storage of water for summer irrigation use is not new to New
Zealand, but its use on the scale proposed is new. For the same reason, the proposal is at the cutting
edge of best practice water and land management providing for the implementation of the National
Policy Statement (Freshwater Management) through imposition of quality and quantity limits in
combination with large-scale irrigation storage and irrigation use.
Finally, the Scheme has national significance because it affects more than one district. The activities
associated with the RWSS are located in the Central Hawke’s Bay District and the Hastings District,
whose Councils have jurisdiction for the control of land uses in each district respectively.
Additionally, the activities of taking water and the discharge of water and contaminants to water,
land and air fall within the jurisdiction of HBRC.
1.3 Resource Consent Applications, Notice of Requirement and Proposed Conditions
The resource consent applications being lodged with the EPA are contained in Part A – Resource
Consent Applications. The Notice of Requirement is contained in Part B – Notice of Requirement, and
proposed conditions of any consents that may be granted are contained in Part D – Proposed
Conditions.
1.3.1 District and Regional Consents
Comprehensive land use consent applications cover the activities associated with the Scheme within
the administrative jurisdiction of each of the Central Hawke’s Bay District Council (hereafter referred
to as CHBDC) and Hastings District Council (hereafter referred to as HDC).
Applications for a total of fifteen resource consents cover those aspects of the Scheme within the
administrative jurisdiction of the HBRC. The first twelve applications are structured in a manner
whereby there is a single comprehensive resource consent application for the construction,
operation and maintenance of each key element of the RWS Scheme (or group of similar activities)
along with separate resource consent applications for the damming, diversion, take, use and
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discharge of water associated with each of the various elements of the RWS Scheme as required
(post construction). In addition, there are two regional land use consent applications, one for the
use of production land, and the other for plantings within a Flood Control Scheme area, and an
application for a coastal permit to authorise deposition of sediment within the Coastal Marine area
to the north and south of the mouth of the Tukituki River for the purposes of beach nourishment.
The aspects of the RWS Scheme that are permitted activities and which are not therefore the subject
of any notice of requirement or a resource consent application are:
• The pipelines making up the secondary distribution system
• The 33kV electricity lines
• Bridges associated with the primary distribution system headrace canal within Zones A - D.
1.3.2 Notice of Requirement
A notice of requirement being lodged with the EPA is contained in Part B – Notice of Requirement. It
falls within the administrative jurisdiction of the CHBDC and covers the proposed primary headrace
canal and pipelines located within Zones A to D.
The Notice of Requirement and (if confirmed) the designation it relates to, perform a dual role:
• It provides consent for HBRIC Ltd to construct, operate and maintain the primary water
distribution canal and pipeline system from a district land use perspective
• It constrains third parties from undertaking activities within the corridor the subject of the
Notice of Requirement that have the effect of preventing or hindering HBRIC Ltd’s ability to
undertake the works covered by its Notice of Requirement without HBRIC Ltd’s consent.
Schedule 3 in Part B contains greater detail on the restrictions in question.
The Notice of Requirement has a separate set of conditions in Part D of the application suite. Key
conditions are those requiring HBRIC Ltd to submit an outline plan to CHBDC and a narrowing of the
designated corridor following completion of detailed design.
The outline plan procedure is provided for in the Resource Management Act 1991 as a formal
process for ensuring the consent authority (in this case CHBDC) has an input into the process by
which relatively generally expressed designations are converted to detailed plans and specifications.
The condition requiring narrowing of the corridor reflects the fact that detailed design of the works
the subject of the Notice of Requirement has yet to occur. The condition ensures that when detailed
design has been undertaken, the designated corridor is narrowed to cover only that land which is
ultimately required for the designated works.
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At present, the proposed conditions for the Notice of Requirement cross refer and incorporate the
conditions in Schedules One and Two of Part D. This is because the Notice of Requirement covers
similar activities to many of the resource consents that have been sought and should meet the same
standards in relation to construction, operating and maintenance. Because the wording of the
relevant conditions could change during the hearing process, they have been kept together in Part D
as one set covering all consents, along with the Notice of Requirement. The intention is, however,
that when the wording is settled, the conditions relevant to the Notice of Requirement will be
separated out from Schedules One and Two and incorporated into the specific conditions for the
designation so that they form one standalone set of conditions for that element of the RWSS.
Consideration of the Notice of Requirement requires an assessment of alternatives and for that
reason, Schedule 4 of Part B contains an analysis of alternatives.
1.3.3 Proposed Conditions
HBRIC Ltd has prepared sets of proposed conditions to accompany the applications which are
contained within Part D – Proposed Conditions. The proposed conditions are discussed in greater
detail in Section 1.4 and 1.10 below.
1.4 Management Plan Approach
A feature of the Proposed Conditions in Part D is the provision of a number of Management and
Monitoring Plans to govern both the construction and future operation of the Dam and Distribution
System. These are described and explained below:
• A Construction Environmental Management Plan (CEMP) which will generally follow the
draft set out in Schedule Six of Part D – Proposed Conditions. The CEMP will be finalised
once the main contractors are appointed and prior to construction commencing. The
proposed conditions provide that during that finalisation process, matters of detail in the
Scheme design as set out in the Project Description (Tonkin & Taylor, May 2013a)) may
change, provided the objectives and performance standards set out in the Draft CEMP and
conditions are still met and any change does not cause any greater environmental effect.
The proposed conditions also provide a process for more significant variations from the
Scheme design as set out in the Project Description, subject to specific safeguards. In
particular, it is envisaged that in the detailed design process, the exact location and the
design elements of the dam structure and related diversion tunnel, spillway and power
station structures may change. The proposed conditions make it clear that this is permissible
provided the works occur within the area identified in the consent application plans; that the
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change results in an outcome which meets or exceeds the relevant specified engineering
design standards, and is of no materially greater or different effect in relation to
environmental outcomes. A dual certification process is required whereby the engineer
responsible for the Scheme design certifies that the variations meet or exceed the dam
design criteria relevant to dam safety, and that opinion is confirmed by a second engineer
approved by HBDC and CHBDC. A similar process is provided for changes to the upstream
and downstream water intake structures, but without the added process step of a second
engineer’s opinion because the same potential safety issues do not arise for such changes to
the design of those structures.
• To ensure that an appropriate level of environmental management is applied, all principal
components of the RWSS will require Supplementary Construction Environmental
Management Plans (SCEMPs). These SCEMPs are location or activity specific and will be
prepared in accordance with the objectives and performance standards outlined in the Draft
CEMP and conditions.
• An Emergency Action Plan (EAP) to ensure appropriate management of the risk associated
with unplanned abnormal or excessive flow releases from the Dam.
• A Water Level Safety Plan (WLSP) to detail procedures (signage, warning sirens, and public
information) to warn of the risk to public safety of planned sudden operational changes in
river flows along the Makaroro River below the Makaroro Dam at points accessible to the
public.
• A Reservoir Filling and Edge Rehabilitation Plan (RFERP) to minimise (inter alia) as far as
practicable the loss of indigenous fauna and manage clearance of vegetation and reservoir
edge erosion resulting from construction earthworks, vegetation removal and reservoir
filling. The RFERP will also address optimisation of public access and recreation
opportunities associated with the reservoir.
• A Construction Traffic Management Plan (CTMP) to ensure that traffic generated during the
construction phase of the Scheme is effectively managed so that increases in traffic volume
are safely accommodated within the existing road network.
• An Infrastructure Stormwater and Maintenance Management Plan (ISMMP) governing
stormwater management (including oil containment) and maintenance activities on
structures forming part of the RWSS.
• A Sediment Management Plan as described in Sedimentation Assessment (Tonkin & Taylor,
May 2013b) dealing with the management of sediment, gravel and dust in the reservoir, river
system and coastal environment.
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• A Groundwater Monitoring Plan (GMP), to identify and monitor the quality of existing bores
utilized for the supply of human drinking water prior to and post the exercise of the
consents, including actions to be taken by Scheme users upstream from such bores where
there is potential to exceed Drinking Water Standards as a result of the consents being
exercised.
• A Groundwater Mounding and Drainage Monitoring Plan (GMDP) to monitor groundwater
mounding in areas identified as susceptible to surface and near-surface effects resulting from
the groundwater table rising, and to provide for effective management of that risk.
• An Irrigation Environmental Management Plan (IEMP) and associated Farm Environment
Management Plans (more particularly described in Section 7 of this document) which
describes how irrigation users who join the Scheme will be required to interact with HBRC’s
planned sustainable water quality regime in the Tukituki Catchment.
• An On Farm Monitoring Plan to cover monitoring of soil conservation on a range of irrigated
and non-irrigated properties within the Ruataniwha and Papanui Basins to provide
information to improve the ongoing effectiveness of the FEMPs.
All of these Management and Monitoring Plans are incorporated in, or are required to be prepared
pursuant to Part D – Proposed Conditions. The proposed conditions require each management plan
to be certified by the relevant consent authorities against set objectives, performance standards
and/or matters to be addressed.
1.5 Integrated Assessment of Environmental Effects
This Part C Assessment of Environmental Effects document has been produced covering both the
district and regional related aspects of the Scheme.
1.6 HBRIC Ltd
The applicant is HBRIC Ltd, which was established in February 2012 and is wholly-owned by the
HBRC. HBRIC Ltd took over responsibility for the RWSS following the completion of the feasibility
stage of the Scheme in late 2012.
HBRIC Ltd is a council-controlled trading organisation (CCTO) for the purposes of the Local
Government Act 2002. For an initial period from February 2012 to December 2013, HBRC appointed
a Transition Board comprising seven directors - three Councillors and three external directors, and
ex-officio, the Council’s Chief Executive as Managing Director. It is intended that the Transition
Board will be replaced with an ongoing Board after December 2013, with the Transition Board
directors being eligible for re-appointment.
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HBRIC Ltd acts as the holding company for the Council’s commercial investments. As at the date of
this application its sole operating investment was the 100% ownership of the Port of Napier valued
at $177 million in April 2012.
The company’s other major investment is the RWSS in which it will complete remaining investigation
and feasibility studies. If resource consents are granted and further commercial analysis justifies
investment in water harvesting and storage, HBRIC Ltd is likely to become a partner with other
investors in the construction and ownership of the Scheme.
The structuring of that investment has yet to be resolved. But if, as is likely to be the case, a new
entity is formed for this purpose, HBRIC Ltd will continue to hold and have financial responsibility for
the designation covering the primary water distribution system and will contract with the new entity
to ensure the terms of the designation are complied with. This approach is consistent with that
adopted by Central Government in recent public and private partnership projects in New Zealand
such as the Wiri Mens Prison project in South Auckland. HBRIC Ltd was approved as a requiring
authority pursuant to section 167 of the Resource Management Act 1991 on 20 March 2013.7
1.7 AEE Report Structure
The structure of this Assessment of Environmental Effects (AEE) is as follows:
Table 1.7 Assessment of Environmental Effects Content Outline
Section Assessment of Environmental Effects Content Outline
1 Provides background information on HBRIC Ltd, explains the national significance of the
proposed Scheme, and lists the technical studies undertaken which are relevant to the
applications, along with management and monitoring plans that will govern the
Scheme’s operation
2 Describes the process for the development of the Scheme
3 Describes the Tukituki River System and Existing Environment so as to form a basis for
subsequent effects assessment in Sections 15-27
4 -5 Describes the physical plant proposed to be constructed and operational regime used in
the effects assessments in Sections 15 -27
6 Describes Flow Optimisation Analysis and Modelling for the catchment if the RWSS
7 Refer The Resource Management (Approval of Hawke’s Bay Regional Investment Company Limited a Requiring Authority) Notice 2013, NZ Gazette, 28 March 2013, number 1888.
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proceeds
7 Describes the Irrigation Environmental Plan to manage adverse environmental effects
consequential on the use of the irrigation water to enable intensification of production
land uses
8 Describes the proposed integrated mitigation offset programme proposed to address
environmental effects
9 Discusses the RMA framework for this application
10 Introduces the Modelling Reports
11 Summarises the Groundwater / Surface water Flows Modelling
12 Summarises the Tukituki River In-stream modelling reports assessing nutrient issues
13 Summarises the results of Groundwater – Drinking Water Modelling
14 Describes the assessment methodology used in the AEE
15-27 Assesses potential effects associated with the project, and describes suggested
approaches including mitigation measures for those adverse effects identified
28 Identifies those persons interested in or affected by the proposal and provides an
overview of consultation undertaken
1.8 Studies Undertaken
A number of reports have been commissioned to describe the processes and technical inputs of the
Scheme and to investigate and report on environmental, cultural, social, and economic effects.
The investigations undertaken have provided a comprehensive analysis of the environmental issues
associated with the proposed RWSS that are required to be assessed under the RMA. The reports
are summarised in this document and form part of the Assessment of Environmental Effects for the
purposes of the resource consent applications made in Part A – Resource Consent Applications and
Part B - Notice of Requirement.
Copies of all these reports can be found in the associated CD-ROM and on the HBRC website.
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Table 1.8.1 - Key Reference Reports
Key Reference Reports
Short Title Date Organisation Reference CD-Rom
Number
Project Description May 2013 Tonkin & Taylor Tonkin & Taylor (May
2013a)
K1
Zone M Headrace Concept May 2013 EMS EMS (May 2013a) K2
Climate Change Review May 2013 J A Renwick Renwick (May 2013) K3
Environmental Flow
Optimisation
May 2013 Aquanet
Cawtrhon
Tonkin & Taylor
HBRC Science
Aquanet (May 2013) K4
Irrigation Environmental
Management Plan (IEMP)
May 2013 HBRIC Ltd HBRIC (May 2013e) K5
Integrated Mitigation & Offset
Approach
May 2013 HBRIC Ltd HBRIC (May 2013f) K6
Table 1.8.2 - Modelling Reports
Modelling Reports
Short Title Date Organisation Reference CD-Rom
Number
Ground & Surface Water Flow
Modelling
May 2013 HBRC Science HBRC Science (May
2013a)
M1
OVERSEER® Nutrient Budgets
Modelling
May 2013 AgResearch AgResearch (May
2013)
M2
Stream Modelling (TRIM2
Calibration)
May 2013 NIWA NIWA (May 2013a) M3
Stream Modelling (TRIM2
Scenario Modelling)
May 2013 NIWA NIWA (May 2013b) M4
Groundwater Drinking Water
Modelling
May 2013 HBRC Science HBRC Science (May
2013b)
M5
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Table 1.8.3 - Assessment Reports
Assessment Reports
Short Title Date Organisation Reference CD-Rom Number
Planning Assessment May 2013 EMS EMS (May 2013b) A1
Reservoir Water Quality
Assessment
May 2013 NIWA NIWA (May 2013c) A2
Aquatic Ecology
Assessment
May 2013 Cawthron
Institute
Cawthron (May
2013)
A3
Terrestrial Ecology
Assessment
May 2013 Kessels and
Associates
Kessels and
Associates (May
2013)
A4
Cultural Impact
Assessment
June 2012 Taiwhenua ō
Tamatea &
Taiwhenua ō
Heretaunga
Taiwhenua ō
Tamatea &
Taiwhenua ō
Heretaunga (June
2012)
A5a
Cultural Impact
Assessment – Zone M
Addendum
April 2013 Taiwhenua ō
Tamatea
Taiwhenua ō
Tamatea (April 2013)
A5b
Social Impact
Assessment
May 2013 Taylor Baines Taylor Baines (May
2013)
A6
Regional Economic
Impact Assessment
May 2013 Butcher
Partners
Butcher (May 2013) A7
Archaeological
Assessment
May 2013 Clough and
Associates
Clough and
Associates (May
2013)
A8
Recreation Assessment May 2013 OPUS OPUS (May 2013a) A9
Road and Traffic
Assessment
May 2013 OPUS OPUS (May 2013b) A10
Noise Assessment May 2013 Marshall Day Marshall Day (May
2013)
A11
Landscape and Visual
Assessment
May 2013 Isthmus Group Isthmus (May 2013) A12
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Dam Break Assessment May 2013 HBRC
Engineering
HBRC Engineering
(May 2013)
A13
Sedimentation
Assessment
May 2013 Tonkin & Taylor Tonkin &Taylor (May
2013b)
A14
1.9 External Peer Reviews
Certain key technical reports that have been prepared to accompany this application have not only
been subjected to internal review processes, but have also been peer reviewed by external experts
to provide additional quality assurance. These are set out in the table below.
Table 1.9.1 - Table of Key Reports Externally Peer Review
Key Reference Reports
Short Title Date Organisation Reference Peer Reviewer
Environmental Flow
Optimisation
May 2013 Aquanet Aquanet (May
2013)
David Leong
(Tonkin & Taylor)
Modelling Reports
Short Title Date Organisation Reference Peer Reviewer
Ground & Surface Water Flow
Modelling
May 2013 HBRC Science HBRC Science
(May 2013a)
David Leong
(Tonkin & Taylor)
Hugh Middlemis
(RPS Aquaterra)
Groundwater Drinking Water
Modelling
May 2013 HBRC Science HBRC Science
(May 2013b)
Hugh Middlemis
(RPS Aquaterra)
Assessment Reports
Short Title Date Organisation Reference Peer Reviewer
Aquatic Ecology Assessment May 2013 Cawthron
Institute
Cawthron (May
2013)
Dr Phil Mitchell
(Mitchell
Partnerships)
Terrestrial Ecology Assessment
May 2013 Kessels &
Associates
Kessels &
Associates (May
2013)
Dr Vaughan
Keesing
(Boffa Miskell)
Dam Break Study May 2013 HBRC HBRC Engineering David Leong
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Engineering (May 2013) (Tonkin & Taylor)
Sedimentation Assessment May 2013 Tonkin &
Taylor
Tonkin & Taylor
(May 2013b)
Dr Murray Hicks
(NIWA)
In addition, the TRIM2 Modelling Reports (NIWA, May 2013(a) and NIWA, 2013(b)), have had input
from Dr Ian Webster ex CSIRO in Melbourne, now consulting in his own right. In particular, Dr
Webster has discussed the approach taken in the NIWA reports with their author (Dr Kit Rutherford)
and has provided initial comment identifying areas for improvement, principally relating to the
desirability of undertaking additional sensitivity analysis. At the time of completing the NIWA
Reports, Dr Webster was unavailable to complete his formal Peer Review of the finalised documents
and it is intended that he and Dr Rutherford will confer again when he is available to discuss future
work on testing the sensitivity of the modelling. Any additional updates will be provided by Dr
Rutherford in his evidence to the hearing.
1.10 Proposed Conditions
This Assessment of Environmental Effects and the supporting reports outlined in the tables above
needs to be read together with the proposed conditions set out in Part D – Proposed Conditions.
The structure of the proposed conditions recognises the degree of overlap between the resource
consents and designation applied for. Accordingly:
• The construction related activities are subject to a single set of conditions in Schedule One of
the proposed conditions.
• Conditions related to Operations and Maintenance activities are similarly collected together
in Schedule Two of the proposed conditions.
• Production land use activities are governed by Schedule Three of the proposed conditions.
These conditions apply both within the five defined irrigation zones (Zones A-D and M) and
to the use of RWSS water by existing irrigation consent holders outside those zones. The
latter have water permits of their own (as will some water users within Zones A-D and M),
but it will be a contractual condition of water supply to them that they comply with the
obligations arising from the proposed Schedule Three conditions in respect of their entire
properties irrespective of whether they choose to retain their existing resource consents.
In addition, several of the consents have specific conditions proposed relating only to that consent
(or designation). As already noted, while Schedules One and Two relating to Construction and
Operations & Maintenance currently contain conditions applying to the Notice of Requirement, it is
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intended that the relevant conditions will be split off later in the application process so that the
designation (if confirmed) has its own standalone set of conditions for ease of administration.
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2 SCHEME DEVELOPMENT PROCESS
This section provides a description of the process that has been followed in the development of the
RWSS culminating in the finalisation of a comprehensive Project Description (Tonkin &Taylor 2013a)
which forms the basis of the RWSS applications.
2.1 Identification of Scheme Potential
Hawke’s Bay suffered a series of droughts over a four year period from 2006 - 2009. According to
MAF estimates at the time, the negative economic impact for the region was in the order of
hundreds of millions of dollars. In 2007, 153 water take consents were renewed through a notified
consent process. However, due to the uncertainty regarding the sustainability of these takes, the
consents were assigned a relative short duration of five years and are due for renewal through 2013
to 2015. Furthermore, since 2007 no new water take consents have been granted within the
Tukituki catchment.
In 2008 HBRC reviewed its regional water strategy and determined a number of objectives or issues:
• When managing freshwater allocation and quality issues, a supply and demand framework
would be utilised, especially in catchments where allocation limits had been reached
• When managing freshwater resources, Regional Councils have traditionally concentrated on
“supply side” allocation
• Somewhat aspirationally, there was a need to speed up the implementation of strategy and
policy so as to get plan changes and / or rural water management projects underway in a
timelier manner.
In developing a series of initiatives to meet these objectives, HBRC determined (inter alia) that it
should initiate water storage prefeasibility and feasibility projects in catchments where the initial
evidence pointed towards the need for infrastructure solutions for water use. The RWSS was
identified as one such project.
2.2 Pre-Feasibility Studies
The RWSS pre-feasibility level investigations into winter flow harvesting to storage dams in Central
Hawke’s Bay were completed in June 20098. As discussed in Section 2.4 below, the Tonkin & Taylor
study identified a range of possible off-river storage dams. Reports were also compiled on the value
8 Pre-feasibility Study of Water Augmentation Opportunities Ruataniwha Plains - Tonkin & Taylor June 2009.
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proposition and suggested commercial arrangements. An environmental gap analysis was also
completed.
2.3 Feasibility Study
The first stage of the full feasibility study9 established leadership and stakeholder groups and saw
the completion of an initial water demand assessment to identify the irrigation zones to be served.
An initial fatal flaw analysis to identify the costs and most economic dam sites and distribution layout
was completed. Geotechnical and seismic issues reduced the number of potential dam sites and
ultimately identified the selection of the preferred site the subject of these applications.
The subsequent stage of the full feasibility study was initiated in January 2011. The purpose of the
full feasibility study was to undertake sufficient investigation and assessment of effects to be able to
establish the technical, commercial and environmental feasibility, and of the development of a
storage dam at the favoured Makaroro site; and the associated supply distribution to the farm gate
across proposed irrigation zones making up the likely Ruataniwha Plains service area.
More than thirty key environmental (including social and cultural) technical, and economic
assessments were undertaken throughout the full feasibility phase involving expert advisors from a
wide cross-section of disciplines, as well as technical input from within HBRC’s own professional
staff.
The land use intensification study was a large and important component of the environmental study
package, drawing significant resources to advance knowledge and understanding of the potential
effects associated with both current and more intensive land use on the Ruataniwha Plains.
Engagement through Leadership, Stakeholder, Mana Whenua, Pan Sector and Landowner groups
was ongoing from the outset of the full feasibility process.
The full feasibility study culminated in a report10 to the Regional Council in September 2012. On 31
October 2012, HBRC Councillors voted for the RWSS to move forward to resource consent
application stage. As already noted, HBRIC Ltd took over responsibility for the Scheme following that
decision.
9 Ruataniwha Plains Water Augmentation Scheme - Advanced Pre-feasibility Study - Summary Report February 2011 10 Ruataniwha Water Storage Project - Feasibility Report to Council - Report No. WI 12-24 September 2012
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2.4 Alternatives Assessment - Scheme Refinement
The RMA requires11 that where it is likely that an activity will result in any significant adverse effect
on the environment, the AEE shall include a description of any possible alternative locations or
methods for undertaking the activity. Case law indicates that complying with this requirement
involves a description of alternatives tailored to the nature and scale of effects (the greater the
adverse effect, the greater the level of detail in the description of alternatives) but there is no
obligation to demonstrate that the chosen alternative is the best one and the consideration of
alternatives is limited to the region or district of the consent authority12.
The following sections outline the process undertaken to consider alternatives and the rationale for
selection of the proposed site that is the subject of this consent application.
2.5 Smaller Off-river Storage Sites versus In-river Dam Approach
The pre-feasibility study referred to in Section 2.2 above was based on the self-imposed constraint
that on-river storage dams (particularly large dams) on any of the main rivers would have higher
environmental impact and consenting challenges, issues associated with the substantial gravel bed
load from the ranges which would be trapped in such a reservoir (dead storage), and to a degree,
greater problems with distribution of water from one or more large dams over a large service area.
Hence the initial preference was to look at a range of smaller off-river storages utilising natural
valleys that could be filled from a combination of run-off and adjacent rivers during periods when
flows were elevated and there was little demand on water resources.
Taking into account the area to be covered and likely water use, Tonkin & Taylor’s June 2009 storage
identification study involved a desk assessment and subsequent identification of fourteen short-
listed sites.
From the shortlisted sites, and after further investigation, a scheme requiring six storage dams was
identified with potential to service full demand for irrigation water across the four zones on the
Ruataniwha Plains.
Tonkin & Taylor considered that for the six proposed storage sites, the local runoff provided, on
average, only a small proportion of the storage infill necessary and water harvesting would be
required from principal rivers located nearby. It was anticipated that this would be achieved using
either gravity or pumped river intakes. Storage refill assumed winter-only flow harvesting from April
to October when flows are naturally higher, with an appropriate environmental flow retained in the 11 Schedule Four section 1(b) 12 Meridian Energy Limited v Central Otago DC [2010] NZRMA 477 (High Court)
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adjacent river for protection of in-stream values. Potential summer capture from any high river flows
was conservatively ignored. Tonkin & Taylor considered that when the scheme was fully developed,
the average volume of surface water abstracted on an annual basis would be less than 6% of the
river flow otherwise exiting the Ruataniwha basin.
This initial pre-feasibility work was supplemented by the advanced feasibility study referred to in
Section 2.3 above to assess and refine the options further. As the study of alternatives progressed
further Tonkin & Taylor re-evaluated its self-imposed constraint of avoiding large in-river dams. The
study introduced the further concept of investigating dams on significant tributaries which avoided
the lower reaches of the main rivers of the plains. The reasons behind this widening of scope
included:
• That the geologically feasible off-river options offered little excess capacity (over the
required capacity), and there were limited replacement options if one or more of the
identified storages was found to be flawed
• Recognition of the geological risk at one of the “anchor” sites in the shortlisted group of six
(Duck Creek)
• Based on interim cost estimates, the cost escalation of off-river options from a variety of
factors, including high seismic design requirements and replacement of pumped mill
transfers with gravity systems which avoid energy costs for pumping but which are
considerably longer and more costly at the outset
• Expected economies of scale (i.e. lowest cost per cubic metre of stored water) offered by
larger and higher capacity on-river storage dams.
The February 2011 Tonkin & Taylor study also recognised the following on-river storage benefits over
off-river storages:
• The requirement for storage infill from an external water source (i.e. transfer of water from
an adjacent waterway) which can have a high capital cost if based on a gravity transfer
system is eliminated
• Significant potential to augment natural low flows in the downstream river
• Hydropower generation potential
• More efficient use of storage resulting from dynamic refill during the irrigation season
through capture of summer floods and freshes
• Potential for stocked fishery in the reservoir
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• Modest downstream flood mitigation benefit from reservoir storage attenuation
• Trapping of bedload in the reservoir could alleviate to a small extent any riverbed
aggradation problem downstream.
As a result of including on-river dam sites as part of the alternatives evaluation, two further dam
sites were identified - A7 on the Makaroro River (the subject of these applications) and D5 on the
Makaretu River. The on-river dams were found to be more cost-effective than the off-river options
partly because of the economies of scale, since larger storage capacities were able to be sustained
and partly because separate (and more costly) in-fill transfer systems were not needed. Analysis of
the cost and storage capacity for all options demonstrated a general inverse relationship between
the unit cost of storage (inclusive of transfer) and the size of the storage; that is, the smaller storages
were found to be relatively expensive compared with their service capacity while the larger storages
were more cost-effective.
Particularly on cost-effectiveness grounds, HBRC selected the two larger dam sites for more detailed
investigation, including development and costing to pre-feasibility level of a supply distribution
system anchored by the two dams. Subsequently the Makaretu site was disregarded due to
geotechnical concerns, and the Scheme focussed solely on the Makaroro site built to a capacity
capable of meeting irrigation requirements and environmental flows for the Tukituki catchment.
This latter point was seen to provide significant opportunity to achieve environmental gains for the
improvement and sustainability of existing riverine habitats that might serve to mitigate any adverse
effects arising from the construction of the upstream dam.
2.6 On-farm Storage Schemes
During the consultation process, and in a number of responses to the Tukituki Choices document
canvassing different options for development of Tukituki catchment planning, it has been suggested
that the environmental objectives of the Scheme could be achieved by building on-farm storage for
irrigation purposes.
The presumption appears to be that farm owners will build such storage in their own right if it is
justified by the economics of changed land uses, and that the provision of large community storage
schemes such as envisaged under this application will result in a disproportionate economic burden
falling on parties who do not stand to gain directly from its objectives.
HBRIC Ltd considers that on-farm storage does not provide a viable alternative to the RWSS. The
reasons are as follows:
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Invalid Comparison - Primary versus Secondary Source
The Scheme intends to provide a primary source of irrigation for land owners who choose to join.
The Scheme has been designed to deliver water to the farm gate at 5mm per day (0.579l/s/ha) based
on a range of possible land use scenarios. It is based on high level of drought reliability and a
seasonal volume of 5,315 cubic metres per hectare with a seasonal volume cap at the 85th percentile.
As the Scheme is a primary source of irrigation, it will displace existing groundwater and surface
water takes by landowners who seek to have water provided by the Scheme and who hold existing
consents. This is an important environmental objective of the Scheme.
Very few farms have sufficient on-farm storage to supply an entire irrigation season. On-farm
storage is primarily a secondary source of water. Macfarlane Rural Business advisors estimate13 that
on-farm storage typically ranges in size from 300 - 1200 cubic metres per hectare, with a median of
around 600-700 cubic metres, or about 10-15 days of storage.
This is well short of the supply security provided by the RWSS.
Inefficient Use of Productive Land
If an average irrigated area of 100 ha was required to be supplied by secondary on-farm storage at,
say, 650 cubic metres per hectare, the farm would need to store 65,000 cubic metres. Assuming the
area for storage was 2.5 metres depth, this would require a total area of 2.6 hectares of land which
would be further increased after allowing for waste area around the pond and pond banks, to 3.0
hectares.
To provide a primary source of water such as that proposed by the Scheme (5,315 cubic metres per
hectare), this storage area would need to increase to 25 hectares assuming that it were even
possible to source the required in-fill storage.
Put another way, in order to generate the same capacity as the proposed RWS scheme it would be
necessary to build over 1,000 average sized on-farm dams occupying thousands of hectares of
productive farm land.
Non-achievement of Wider Environmental Objectives
As an alternative, on-farm storage does not provide the integrated Tukituki catchment management
environmental outcomes that are sought by HBRIC Ltd and which can be significantly achieved
through the RWSS. In particular:
13 Correspondence from MRB to HBRC 26 July 2012
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• An increase to low flows in the catchment river system as current surface and ground water
abstractions are migrated to the Scheme water would not be achievable
• The provision of minimum flows through reservoir water reserved for that purpose would
not be possible
• Use of flushing flows aimed at controlling periphyton biomass in the Makaroro, Waipawa,
and Tukituki rivers would not be achievable
• The ability to use contractual mechanisms to introduce and enforce nitrate-nitrogen and
phosphorus discharge limits through Farm Environment Management Plans entered into by
famers joining the Scheme, would be compromised to the extent that HBRC would need to
rely upon a slower implementation via the provisions of Change 6.
2.7 Primary Distribution System – Zones A to D
The Scheme includes a primary distribution system for Zones A to D that has been designed and
assessed in the context of s171 of the RMA (assessment of alternatives), as this aspect of the water
distribution network will be designated, including as to what alternative options or locations might
be used to undertake that activity.
A report prepared by EMS (Alternatives Assessment for Primary Distribution System - Zones A to D)
in Schedule Four of Part B forms part of the suite of documents accompanying this application,
describes the process of selecting the proposed headrace and distribution network from a range of
alternative options.
The upstream water intake structure on the Waipawa River is located near the 260m RL contour
(Hawke’s Bay datum). The intake site was initially selected from the approximate reach of the river
that could potentially provide the required water level (at least 250m RL) to maximise the area of the
scheme that could be fed by gravity. The location of the intake was selected based on the expected
river morphology, site topography and the presence of a favourable rock outcrop at the outside
bend of the current river channel. No other suitable intake sites to feed Zones A to D were found by
Tonkin & Taylor Ltd on the Waipawa River, within the required elevation range.
The irrigation zones were mapped as part of the pre-feasibility and feasibility investigations
described above in Sections 2.2 and 2.3. Concurrently, a number of planning constraints were
identified and mapped alongside the proposed dam footprint, irrigation zones and distribution
corridor to identify areas where potential issues could arise. Planning constraints included features
such as QEII parcels, registered archaeological, cultural, and historic sites and buildings, significant
landscapes and natural features, DoC conservation units, planning zones, and major energy
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infrastructure networks. This early screening phase ensured factors likely to be of significance under
Part 2 of the RMA were identified at the outset and informed the initial selection of alignments so as
to substantially avoid impacts on such resources and values.
The topography of the area and the elevation of the intake site acted as further constraints for the
alignment of the primary distribution system, and any headrace canal component in particular, in
terms of maximising gravity fed supply.
After further development and costing of alternative distribution pipeline options, a baseline
landscape assessment was undertaken to inform subsequent multi criteria analysis of five
conveyance and alignment options by a team comprising experts in planning, landscape and
engineering, through which, two preferred options were identified. A further landscape and visual
assessment was undertaken of the hybrid (headrace canal and pipeline) conveyance option selected
through the multi criteria analysis.
Overall, the assessment concluded that the degree of residual adverse landscape or visual effects
would be relatively modest for a Scheme of this type. Landscape experts (Isthmus) suggested further
measures to mitigate residual adverse effects and enhance amenity include implementing landscape
principles and guidelines for the detailed design of the headrace. Following further design
optimisation and refinement of the two selected options, a preferred hybrid option was discussed
with landowners.
For that purpose, HBRIC Ltd mapped the refined hybrid alignment/conveyance option, identifying
the properties potentially affected by the headrace canal. Property owners were provided with
maps identifying the proposed canal alignment and in some instances suggested minor realignment
options for consideration in future optimisation works, to better suit their farming operations and
existing property infrastructure. This resulted in some changes to the final canal alignment,
conversion of a previous section of canal in Zone A to pipeline and rerouting of the pipeline along
road reserves.
The primary distribution system for Zones A to D proposed comprises an open canal headrace
totalling approximately 18km in length and extending through Zones B, and C with the pipeline
component extending over a further 18km within Zones A, C and D.
2.8 Liaison with Regulatory Authorities
CHBDC, and HBRC in their role as the main regulatory authorities have been represented on the
Stakeholder Group described more fully in Section 28.
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HDC and CHBDC have been involved in a business development planning group convened by
Business Hawke’s Bay that has been looking at future planning for community economic and social
change.
The EPA has directly engaged planners representing HBRC, CHBDC, and HDC to prepare the key
issues reports required by s149G of the RMA, alongside an independent planning advisor. As part of
pre-application completeness checking, Council planners and their planning advisor have provided
feedback on aspects of this Assessment of Environmental Effects, Part D-Proposed Conditions, and
the Planning Assessment (EMS, May 2013b))
2.9 Consultation Summary
The process of consultation is described in Section 28 of this document and has involved constructive
and positive engagement with a wide range of regional stakeholders, mana whenua and other
interested parties. The process is more fully outlined in that section of this document.
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3 TUKITUKI CATCHMENT AND THE EXISTING ENVIRONMENT
3.1 Introduction
This section provides an overview of the existing environment of the Tukituki Catchment by
describing its location, area reference information, natural resources, and current values, together
with likely changes over time where these can be identified.
More in depth hydrological and groundwater information is contained in the Ground & Surface
Water Flow Modelling Report (HBRC Science, May 2013a). The differing values and uses of the
Tukituki Catchment are described in more detail in technical reports accompanying this application
including (but not limited to) the Social Impact Assessment (Taylor Baines, May 2013), Regional
Economic Benefits Assessment (Butcher, May 2013), Cultural Impact Assessment (Taiwhenua ō
Tamatea & Taiwhenua ō Heretaunga, June 2012), the Zone M CIA Addendum (Taiwhenua ō
Tamatea, April 2013)and Recreation Assessment (OPUS, May 2013a), as well as the HBRC document
entitled Tukituki Choices14 (2012). Future changes to climate are discussed in the Climate Change
Report (Renwick, May 2013).
3.2 Location and Area Reference Information and Terminology
The RWSS is located within the Tukituki Catchment which stretches from the Ruahine Ranges to the
coast of Hawke Bay near the Haumoana township. The Tukituki Catchment contains the Ruataniwha
Basin which lies between the Ruahine Ranges in the west and Raukawa Ranges in the east. The
Ruataniwha Basin contains the Ruataniwha Plains, which are the fertile arable river plains or flats,
and the aquifers below, all of which are located in the Central Hawke’s Bay District within the
Hawke’s Bay Region. A number of faultlines (geological features which are commonplace in New
Zealand) are located adjacent to the Ruahine Ranges and near the proposed Makaroro Dam site.
In the 1880’s, the Waipawa River was diverted to join the Tukituki River at its current confluence.
The Papanui Stream, initially fed by groundwater and supplemented by run-off from surrounding
land, now flows down the old Waipawa River Bed in a north north-easterly direction, through the
area defined as Zone M.
Figure 3.2.1 below shows the main features of the Tukituki Catchment (such as the main rivers) and
main features of the RWSS (such as the dam and reservoir location, primary distribution system and
production land areas). Features of Figure 3.2.1 are described in more detail in the sections below.
14 This report is a consultative document that presented four different scenarios for future land and water management for the Tukituki Catchment and was the pre-cursor for the Tukituki Catchment Change 6 (RRMP).
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Figure 3.2.1 – Main Features of the Tukituki Catchment and the Scheme
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3.3 Geological Features
Figure 3.3.1 below shows the geology of the Ruataniwha Basin and illustrates the limestone and
greywacke boundaries.
Figure 3.3.1: Geology of the Ruataniwha Plains (Source: GNS, 2009)
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Figure: 3.3.2 below shows the lithological separations and sub-surface geological formations of the
Ruataniwha Basin.
Figure 3.3.2: West-East Sub-Surface Geology (Source: GNS, 200915)
Figure 3.3.3 below shows the major faultlines adjacent to the Makaroro Dam and Reservoir Site such
as the Mohaka Fault, Ruahine Fault, Makaroro Fault and Wakarara Fault. The figure shows known
active faults (red) and inactive faults (thin black lines) within 10 km of the proposed Scheme.
Geology is from 1:250,000 scale QMap (Lee et al. in press). Abbreviations used are HT, Hinerua
Thrust; PF, Pukenui Fault; LRF, Lookout Road Fault; MF, Mangataura Fault. The A7 dam site
(proposed Makaroro Dam for RWSS) is sited within the Wakarara Block (blue; greywacke) between
the Mohaka and Wakarara faults. (Source: GNS 2011).
15 Undereiner G., White P.A & Meilhac. C., 2009. Groundwater-surface water investigations along the Waipwa River, Ruataniwha Plains, Hawke’s Bay. Institute of Geological & Nuclear Sciences, 2009.
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Figure 3.3.3: Faultlines adjacent to the Makaroro Dam and Reservoir Site (Source: GNS 201116).
3.4 Surface Water Resources
The Tukituki Catchment is made up of 17 sub-catchments (see Figure 3.4.2) with different stream
types ranging from large open braided gravel bed rivers (e.g. Waipawa River) to smaller spring fed
channelised stream (Porangahau Stream). Gravel streams are sourced from the Ruahine Ranges with
some reaches running dry where the river loses water to the Ruataniwha Aquifer. Hill country
streams experience rapid floods and little base flow, whereas groundwater fed streams flowing over
the Ruataniwha Plains commonly have gaining reaches and a more reliable base flow (see Figure
3.4.3). The headwaters originate in the Ruahine Ranges to the west which are wet (receiving more
16 Langridge, R.M.; McVerry, G.H.; Cabeza, M. 2011. A7 Makaroro River dam site – Phase 1B: Updated active fault and surface rupture displacement hazard assessment and acceleration response spectra reassessment, GNS Science Consultancy Report 2011/300.
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than two metres of rain per year) compared with the drier Hill Country sub-catchments to the east
(which receive less than one metre of rain per year). A summary of the key river flow statistics for
the Tukituki Catchment is shown in Figure 3.4.1 below.
Site
Mean Annual Low Flow (7 Day) (litres/sec)
Long-term Mean Flow (litres/sec)
Natural1 Recorded2 Natural1 Recorded2
Waipawa River at RDS 3009 2839 14970 14949
Tukituki River at Tapairu Rd 2865 2534 15830 15150
Tukituki River at Red Bridge 6258 5902 44505 44544
Figure 3.4.1: Key Tukituki River and Waipawa River Flow Statistics (Source: Tukituki Choices, 2012)
Note 1: 'Natural' means that the hydrological statistic was determined based on flow data that has been ‘naturalised'; that is, estimated abstractions during the time of measurement are added back in. It is as if there had been no abstractions.
Note 2: 'Recorded' means that it is the flow series as recorded at the date of measurement with the effect of any abstractions.
Figure 3.4.2: Tukituki Catchment Sub-Catchments
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Figure 3.4.3: Tukituki Catchment Stream Types
3.5 Groundwater Resources
There are two main productive aquifers in the Tukituki Catchment, the Ruataniwha Basin and the
Otane Basin. A third aquifer system at the lower end of the catchment where the river intersects
with the Heretaunga Plains system is referred to as the Lower Tukituki Aquifer System.
The most productive aquifer systems in the Tukituki Catchment are formed in the more permeable
sediments in the Ruataniwha Basin (beneath the Ruataniwha Plains), and at the lower end of the
catchment where the Tukituki aquifer overlaps and merges with the main aquifer system of the
Heretaunga Plains. Smaller productive groundwater resources are found east of the Ruataniwha
Plains, along alluvial deposits of the Waipawa and Tukituki Rivers and along the old Waipawa River
bed and the Papanui Stream near Otane.
3.5.1 The Ruataniwha Basin and Aquifer
The Ruataniwha Aquifer sits in a geologically contained basin referred to as the Ruataniwha Basin
(see Figure 3.2.1 above). Water enters the aquifer when rain falls on land and through losses in some
parts of the rivers that cross the plains. Groundwater is generally moving in a west-east direction
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under pressure and all water leaves or discharges the basin, entering the Tukituki and Waipawa
Rivers via springs or through the river bed and tributaries. The rate of discharge depends on the
pressure in the aquifer system. Pumping groundwater can lower the pressure in the aquifer and
groundwater modelling (HBRC Science, May 2013a) indicates that this has reduced the rate of
discharge into the river system.
3.5.2 The Otane Basin and Aquifer
An aquifer system lies within the Otane Basin (see Figure 3.2.1 above). Groundwater can be found in
most geological formations within the Otane Basin. The most productive aquifer system appears to
be within gravels located beneath both the old Waipawa River bed and the Papanui Stream. Well
depths indicate the aquifer system is deeper at the southern end of the catchment near the middle
of the old Waipawa River bed; in this area, wells penetrate gravels up to 50 metres deep. Further
north, along the Papanui Stream, well lithology suggests alluvium is up to 30 metres thick. Toward
the west, along Drumpeel Road in the middle of the catchment, the aquifer system grades into
swampy deposits from the geologic Quaternary period. The general directional flow of groundwater
within the aquifer is unknown but is thought to move with the topographical gradient from
southwest to northeast along the old Waipawa River bed.
3.5.3 The Lower Tukituki Aquifer System
The Lower Tukituki Aquifer System (see Figure 3.2.1 above) is where the Tukituki River intersects
with the Heretaunga Plains Aquifer System. The Lower Tukituki Aquifer System, like the Heretaunga
Plains Aquifer System, is characterised by inter-bedded layers of gravels with “confining” clay layers.
Groundwater flows in an east to north east direction and discharges out at sea. The Lower Tukituki
Aquifer System is relatively productive and most wells in the area that are screened at depths of
greater than 30 m have water levels above ground (artesian).
3.6 Values
Values and uses of the Tukituki Catchment have been identified in a range of technical reports as
outlined below. The Tukituki Catchment is appreciated for its aesthetic, recreational and cultural
values and its rivers and aquifers are valued for the water it provides for household, stock and public
supply, commercial use and irrigation. This section provides a brief overview of the values and
current uses of the Tukituki Catchment.
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Cultural values • Mauri - the life force • Wahi tapu - sacred places • Tikanga - protocols • Kaiti akitanga - guardianship • Manaakitanga - being good hosts • Mahinga kai - food gathering places • Matauranga Maori - knowledge • Te Reo - language • Taonga - highly prized things
Economic values • Long term economic growth (including potential al) • Flexibility • Investment certainty • Employment opportunities • Reliable water supplies for commercial, industrial and irrigation • Tourism
Ecological values • Healthy ecosystems - life supporting capacity • Biodiversity • Native fish habitats • Trout habitats • Fish passage
Social values • Human and stock drinking water needs • Swimming and fishing • Passive enjoyment • Food gathering • Public access • Lifestyle
Figure 3.6.1: Summary of Tukituki Catchment Values17
3.6.1 Cultural Values
Cultural values and uses are comprehensively documented in Te Taiwhenua ō Tamatea and Te
Taiwhenua ō Heretaunga (June 2012), which defines cultural values as relating to ‘the concept of
holistic ecological health of the land, water, sea and all living things in general that are inextricably
inter-connected with the well-being of mana whenua. These cultural values are conceptualised
through their origin in Te Ao Maori (Maori world view) and understood according to whakapapa
which connects Maori beliefs and values towards, and about the natural environment.’
The report recognises the role that water flows and water quality have in sustaining the mauri of the
Tukituki River. Elements of water flow and water quality that relate to mauri were identified as
including natural character, flow variability, natural energy, rainfall, aquifer recharge, flushing flows,
flows for fish habitats, changing flow paths flooding or exposing wahi tapu18.
Cultural Values and uses in the Zone M sector are discussed a separate addendum Report (Te
Taiwhenua ō Tamatea (April 2013). That report highlights that the Zone M area was an important
place for food gathering and that there are a number of registered and unregistered wahi tapu sites
in the area. The report records the concern Mana Whenua have had and expressed over a number
17 Extracted from Tukituki Choices – HBRC 2012 18 See Te Taiwhenua ō Tamatea and Te Taiwhenua ō Heretaunga, June 2012, Table 3.0.
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of years regarding the loss of mauri in the old Waipawa Riverbed, the Papanui Stream and lakes in
the area.
3.6.2 Social Values
Social values and uses of the Tukituki Catchment identified in the Tukituki Choices (HBRC, 2012)
discussion document included: human and stock drinking, swimming and fishing, passive enjoyment,
food gathering, public access and lifestyle. Social and economic values are detailed in a Social Impact
Assessment report (Taylor Baines, May 2013). Recreational values have also been identified and
described in detail in the Recreation Assessment (OPUS, May 2013a).
3.6.3 Economic Values
Economic values and uses of the Tukituki Catchment identified in the Tukituki Choices (HBRC, 2012)
discussion document and the Regional Economic Impact Assessment (Butcher, May 2013) include
long term economic growth (including potential), flexibility, investment certainty, employment
opportunities; and reliable water supplies for the primary sector and other commercial and industrial
sectors.
3.6.4 Ecological Values
Environmental (ecological) values and uses of the Tukituki River catchment identified in the Tukituki
Choices (HBRC, 2012) discussion document, and in Kessels and Associates (May 2013), Cawthron
(May 2013) and Te Taiwhenua ō Tamatea and Te Taiwhenua ō Heretaunga (June 2012) include, (but
are not limited to):
• Healthy ecosystems
• Life supporting capacity
• Mauri
• Biodiversity
• Significant indigenous flora and fauna habitat
• Native fish habitats
• Trout habitats
• Fish passage.
The terrestrial flora and fauna in the dam and reservoir consent application area are described in
detail in Kessels and Associates (May 2013).
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3.6.5 Landscape Values
The Landscape and Visual Effects Assessment (Isthmus, May 2013) outlines a range of aesthetic
values associated with natural features, landscapes and natural character with the Ruataniwha Plains
essentially comprising a “working landscape” set against the wilderness landscape of the Ruahine
ranges.
3.7 Current Use
The Tukituki River catchment is a largely a rural catchment with a number of townships which service
and support the primary industry sector. Water is taken throughout the Tukituki Catchment from
surface water bodies and aquifers for a range of purposes such as for irrigation, industrial purposes
and drinking water.
The headwaters and upper Tukituki Catchment in the Ruahine Ranges are in native forest, and in
native shrub and tussock above the tree line. Apart from some areas of exotic forestry, and the
native vegetation in the Ruahine Forest Park and some private farmland, the catchment is largely
deforested. Land use in the hill country is predominantly dry stock farming. The Ruataniwha Plains
too have been traditionally set with sheep and beef farms but since the 1960’s agricultural cropping
increased, with horticulture expanding in the 1970’s and dairying since the 1990’s. In the past few
years converting to cropping from traditional dry stock farming and horticulture has increased. The
rest of the upper Tukituki Catchment has some areas of exotic forestry, hill country sheep and beef
farming. In the lower end of the catchment there is more viticulture and horticulture, with a larger
number of small farm blocks and vineyards. Near Havelock North sub-divisions have sprawled since
the 1990’s and near Haumoana small horticultural blocks have remained a steady increase up until
the last decade where some vineyards and orchards have been converted to cropping.
On the eastern edge of the Ruataniwha Plains the river flows past two urban centres, Waipukurau
and Waipawa. The discharge from the municipal sewage treatment plants discharges into tributaries
(Pah Flat Stream and Bush Waterway) of the Tukituki and Waipawa Rivers. Initiatives are underway
to improve the water quality of the discharge, with the CHBDC in the process of upgrading the
municipal sewage treatment plants in order to meet consent conditions requiring a reduction in
phosphorus concentrations by 2014. The existing environment therefore includes that reduction in in
phosphorus inputs to the river below the discharge points, and the consequent reduction in
periphyton biomass accumulation in the lower Tukituki.
The most recent national angler survey rated the Tukituki River as the most heavily fished river in the
Hawke’s Bay Region (and 29th out of 848 nationally). A significant proportion of the anglers fishing
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the river are overseas visitors. The majority of fishing effort occurs in the middle and lower reaches
of the river, below the Waipawa confluence.
The Waipawa River itself is also a popular river in its own right, but only supports 11% of the total
effort expended in the entire Tukituki Catchment. Other tributaries such as the Mangaonuku,
Tukipo, Kahahakuri and Makaroro also provide angling opportunities, but are less important angling
destinations than the mainstems of the Tukituki and Waipawa. However, these tributaries (and
other smaller ones) are important spawning and juvenile trout rearing areas. Some tributaries, such
as the Papanui, provide little contribution to the Tukituki trout fishery or trout population due to low
flows or poor water quality.
Most hill country since deforestation has been in dry stock farming and this remains today.
3.8 Urban Development
3.8.1 Central Hawke’s Bay District
Within the Tukituki Catchment and Central Hawke’s Bay District, the two main towns of Waipukurau
and Waipawa lie next to the Tukituki River and the Waipawa River respectively. Approximately 50
per cent of the District's population (13,500, year ending June 2011) live in urban Waipukurau and
Waipawa that are located outside of the consent application areas in between Zones A to D and
Zone M.
Central Hawke’s Bay District housing is typical of the rural Districts nationally. The average household
unit is becoming smaller, moving towards 2.5 persons per household (CHBDP, 2003). This reduction
in the number per household is particularly evident in the urban areas and has resulted in further
residential building. There is a demand for life-style blocks which is a nation-wide trend with some
people wanting to live in the countryside but work in town (CHBDP, 2003). Both Waipukurau and
Waipawa have CBD’s zoned as Inner Commercial Environment (Business Zone 1, CHBDP, 2003) and
Mixed Commercial and Industrial Environment (Business Zone 2, CHBDP, 2003).
The small rural townships of Tikokino, Onga Onga, and Takapau are within irrigation zones A to D
(although the consent applications do not seek approval for activities within those townships). The
township of Otane is within Zone M although it too is excluded from the area covered by HBRIC Ltd’s
resource consent applications. The CHBDP (Objective 6.2.1 and Policy 6.2.2, 2003) seeks to retain the
spacious appearance of these rural townships by restricting factory farming and extractive industries
in order to ensure that an appropriate level of township amenity is retained, whilst at the same time
enabling a range of businesses to establish and operate.
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3.8.2 Hastings District
Within the Tukituki Catchment in Hastings’s District, is the small coastal settlement of Haumoana
that is located near the Tukituki River mouth. One of HBRIC Ltd’s consent applications relates to
beach nourishment adjacent to the township. Haumoana is part of the Heretaunga Plains Urban
Development Strategy (HPUDS, 2010) which is a long term (2045) joint approach between Napier
City Council, HDC, HBRC and mana whenua. HPUDS aims to assist the local authorities to plan and
manage growth on the Heretaunga Plains.
Haumoana is low lying and parts of it have been subject to flooding, coastal inundation, and coastal
erosion. Infrastructure limitations and topographical considerations generally make the settlement
unsuitable for further growth. There is however a small area of land located off the southern side of
East Road, close to the existing Coastal Residential Zone and to the Suburban Commercial Zone off
Clifton Road, that is free of flooding and coastal hazard constraints and suitable for residential
growth (HPUDS, 2010).
3.9 Social Environment and Community Profile
3.9.1 Central Hawke’s Bay District
A number of marae are located throughout the Tukituki Catchment and Ruataniwha Plains and
Maori settled there in approximately the late 1200’s and 1300’s. The Ruahine Ranges were not
extensively settled by Maori who preferred the lowlands and coastal areas and included tribes from
Ngati Kahungunu, Ngai Tahu, Ngati Apa and Rangitane.
Throughout the early 1800s, there was the arrival of whalers, sealers, traders, settlers and
missionaries. Land purchases and towns and townships were established in the 1850’s and 1860’s.
There are 19 schools (primary and secondary) in the Central Hawke’s Bay District within the Tukituki
Catchment.
The part of the Tukituki Catchment within Central Hawke’s Bay District is well known for its
recreational activities such as fishing and hiking, centred upon the Tukituki River system and the
Ruahine Ranges.
Central Hawke’s Bay District is also well known for farming and is marketed as “Lamb Country”,
promoting the district’s various industries and attractions such as golf courses and wineries.
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Central Hawke’s Bay District covers an area of 333,450 hectares with a population of 13,480 persons
(as of June 2011) and the population is likely to decline by 2.52% to 13,140 persons in 2022 (Statistics
New Zealand, 2011 cited in CHBDC LTCCP, 2012 - 2022).
3.9.2 Hastings District
From about the CHBDC and HDC boundary near the boundary of Zone M until the coastal settlement
of Haumoana lies the Tukituki River valley and bordering hill country farms with a typical rural
setting.
Haumoana is a small coastal settlement with a school, church, General Store, takeaway shop, garage,
hall and Fire Station. The village has developed as a bach (holiday) settlement and lifestyle blocks
and grape growing have become more prominent in recent times. Many inhabitants commute to
nearby cities to work. There are approximately 430 houses within the community
3.10 Terrestrial Ecology and Vegetation
Within the proposed dam and reservoir footprint on private and Crown land there is native forest,
shrub land and tussock land. However, as already noted, apart from exotic forests, the Tukituki
Catchment is largely in pastoral and agricultural cover. A comprehensive assessment of the
terrestrial ecological and vegetation values associated with the existing environment directly
affected by the RWSS and the surrounding area is contained within Kessels & Associates (May 2013).
Ecologically significant indigenous vegetation and habitat is located within the area that would be
flooded by the proposed reservoir. This comprises of mature and secondary indigenous forest
(containing podocarps: matai, kahikatea, rimu, totara and miro); secondary indigenous scrub; gravel
river bed; and wetland or seep zones. Kessels & Associates (May 2013) found one at risk plant
species, namely red mistletoe. A total of 38 bird species (11 endemic) were identified at the
proposed reservoir locality during field surveys. Of these birds 55% were native and 45% introduced.
Threatened or At Risk species comprise 2.5% of all observations, including one pair of the Nationally
Vulnerable New Zealand bush falcon and one adult banded dotterel with a chick. Nationally ‘At Risk’
species detected were pied stilt, New Zealand pipit, black shag and North Island fernbird. Long-
tailed bats were found throughout the proposed Dam and reservoir footprint during ultrasonic
surveys and the report notes that blue duck had recently been identified within 10 kilometres of the
dam and reservoir footprint.
Eleven lizard species are known from the southern Hawke’s Bay region or neighbouring areas of the
southern North Island. However, only one lizard (southern North Island forest gecko) was found
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during the field survey (Kessels & Associates, May 2013). It is not classified as being a nationally At
Risk or Threatened species.
There is a rich diversity of insects and land snails. Two individuals of the At Risk Hawke’s Bay tree
weta have been discovered in the study area.
3.11 Landscape
The Ruataniwha Plains are outwash gravels in a long valley bordered on one side by the Ruahine
Ranges greywacke mountain range and on the other by the Turiri / Raukawa limestone hills. The
valley contains a series of terraces and flood plains. The higher terraces and foothills under the
shadow of the Ruahine Ranges are mostly pastoral farms.
The only outstanding natural feature or landscape in any of the consent application areas is the
Ruahine Ranges as identified in the Hastings District Plan. There are no outstanding natural features
or landscapes identified in the CHB District Plan but the plan does identify six Outstanding Landscape
Views which include the Tukituki River valley, Makaroro River valley and the Waipawa River.
A more detailed analysis of the key landscaping and visual attributes of the surrounding environment
is contained within Isthmus (May 2013).
3.12 Noise Environment
Ambient sound levels in rural areas are generally low due to the lack of significant noise sources and
the dispersed nature of noise sources that do exist. The proposed dam site is surrounded by rural
pastoral farming land and native and exotic forest and scrub. The proposed Primary and Secondary
Distribution Systems including the intake structures is through farmland and along road reserves. At
the coast where the proposed beach nourishment is to occur, the surroundings are a gravel beach,
Hastings Council Sewage Treatment Plant, houses, the Hawke’s Bay trail cycleway and protected
wetlands. Ambient noise levels within these environments are affected by such sounds as:
• Sounds from animals, birds and insects
• Natural sounds from the Makaroro River and sea including water movement, tides,
waves and wind
• Farm equipment and machinery
• Traffic and surrounding roads
• Recreational users such as walkers and fisherman.
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Short-term sound levels at the proposed dam site consent application area are typical of rural areas
and lie in the range of 35 – 55 dBA over varying weather conditions (Marshall Day, May 2013).
A more detailed discussion of the ambient noise environment is contained in Marshall Day (May
2013).
3.13 Traffic Environment
Due to the breadth of the RWSS a high number of Local Authority and New Zealand Transport
Authority roads are located within the consent application areas.
At the proposed RWSS dam site Wakarara Road is the main point of entry and new site access roads
need to be constructed (OPUS, May 2013b).
State Highway 50 connects to Wakarara Road and crosses through the consent application area in
Zones A to D before meeting with State Highway 2 which runs entirely through Zone D. Zone M is
comprised of Local Authority rural roads that connect to State Highway 2.
At the beach nourishment consent application area, Local Authority roads Richmond Road and
Domain Road provide access to the beach.
The existing road environment is described in detail in technical reports OPUS (May 2013b) and
Tonkin &Taylor (May 2013a).
3.14 Air Environment
Air in the Hawke’s Bay Region is generally of a high quality. The area in which the RWSS is proposed
is a rural environment with no major industrial activities or other significant sources of potential
adverse effects on air quality.
The HBRC monitors a number of key ambient (outdoor) air quality parameters, all of which are
included in the National Environmental Standards for Air Quality. The standards for these pollutants
are based on criteria that relate to health and/or environmental effects and are the minimum
requirements that outdoor air quality should meet. HBRC monitoring shows that the parameters are
within safe levels in Hawke’s Bay, with the exception of PM-10. For this reason, the Council monitors
PM10 continuously at a number of locations in Hawke’s Bay while other pollutants are periodically
monitored to check that they remain at safe levels and do not show any worrying trends.
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Key ambient air quality parameters are:
• PM10 – particulate matter that is less than 10 micrometres in diameter
• Carbon monoxide (CO)
• Nitrogen dioxide (NO2)
• Sulphur dioxide (SO2)
• Ozone (O3)
HBRC’s air quality monitoring network includes three stations with automatic beta attenuation PM10
monitors which continuously record PM-10. These are located in Napier, Hastings and Awatoto.
An airshed is an area where air quality is likely, or known, to exceed the NES. There are two airsheds
in the Hawke’s Bay Region, being Napier and Hastings.
There are no identified air quality issues in the Central Hawke’s Bay District and the southern part of
the Hastings District (within which the RWSS is proposed) apart from occasional localised issues such
as dust from agricultural activities and spray-drift associated with the use of agri-chemicals.
3.15 Climate Change
Climate change is now a foreseeable change to the existing environment and the effects of climate
change are a matter to which the RMA decision makers are required to have particular regard.
A report prepared by Dr James Renwick (Renwick, May 2013) discusses the basics of climate change,
and global-scale climate change projections. After discussing factors that influence the New Zealand
climate, climate change scenarios for New Zealand and the implications for the Hawke’s Bay Region
and the RWSS are described.
Climate change projections are based on scenarios of global emissions of greenhouse gases and
aerosols, assuming different social and economic futures. The A1B scenario is often taken as
representative, being in many ways in the mid-range for greenhouse gas concentrations and for
global mean temperature changes. The A1B scenario remains plausible, but in light of recent
emissions, A1B may be conservative in terms of the magnitude of climate change by the end of the
century. However, the difference between the A1B scenario and alternative less conservative
scenarios is unlikely to be sufficiently significant to justify using a different basis for Scheme planning
purposes than the A1B scenario, which has been widely used to date, given the uncertainties around
local-scale predictions.
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Global mean surface temperature rise is likely to be at least 3°C by the end of the 21st century
(compared to the late 20th century) and may reach 4°C or more. The target agreed at the United
Nations Framework Convention on Climate Change meeting in 2009 of no more than 2°C of warming
is virtually certain to be exceeded. Projected rainfall changes through this century follow a broad
pattern of wetter conditions near the equator and poleward of about 45° latitude, and drier
conditions in the subtropics.
Other conclusions reached were:
• New Zealand climate is variable, controlled by the strength of the mid-latitude westerly
winds, which are in turn modulated by the El Niño-La Niña cycle and the Interdecadal Pacific
Oscillation
• Rainfall changes are critically dependent on changes in the westerly winds, which are likely
to increase over the country during winter and spring, and decrease during summer and
autumn
• Temperature rises of between 2° and 3°C are likely in most areas by 2100 (a rate slower than
the global mean warming)
• Rainfall changes are likely to exhibit an east-west gradient associated with changes in the
westerly winds
• Rainfall is likely to increase in winter and spring (5-10% typically) in western regions by 2100,
with similar-magnitude decreases in eastern and northern regions, and associated increased
soil moisture deficits in eastern and northern regions
• Rainfall is likely to decrease in summer and autumn, with increases in rainfall in eastern
regions and decreases in the west and far south (magnitudes on the order of 5%). The
magnitude of projected average changes is well within the range of natural variability, hence
it must be borne in mind that the actual year-to-year (or decade-to-decade) sequence of
change is unlikely to follow a simple linear trend
• Climate change in Hawke’s Bay is likely to be consistent with the scenarios outlined above.
• Temperatures across the whole region are likely to increase by 1-1.5°C by mid-century.
• Temperatures increases in Hawke’s Bay of between 2° and 3°C are likely by 2100.
• Rainfall in Hawke’s Bay is likely to decrease in winter and spring (up to ~5% by mid-century,
and up to 10% by late century)
• Rainfall in Hawke’s Bay is likely to increase slightly in summer and autumn (5-10% by late
century).
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Flows from the headwaters of the Makaroro River are linked to rainfall from western regions
crossing the Ruahine ranges – accordingly, small increases in winter and spring average flows and
small decreases in summer and autumn flows are likely.
The risk of heat waves and drought conditions is likely to increase significantly, while the risk of
frosts and cold nights is likely to decrease. Drought risk is likely to increase most in eastern regions,
including Hawke’s Bay, where a doubling or tripling of the risk is likely by the end of the century. The
risk of heavy rainfall events is also likely to increase, although it is likely this will not become evident
in Hawke’s Bay until the late 21st century.
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4 PROJECT DESCRIPTION SUMMARY
4.1 Project Description Document
The Scheme is comprehensively described in the Ruataniwha Water Storage Scheme – Project
Description (Tonkin & Taylor, May 2013a) which is included on the CD-ROM provided with this AEE.
This section provides a summary based on that document.
This section, and those that follow it, provide the frame of reference for consideration of the RWSS.
They summarise the series of reports labelled as Key Reference (or K) reports in the suite of
supporting documents.
4.2 Scheme Overview
The following map represents the Scheme overview, showing dam location, reservoir extent,
production land use areas and the proposed water distribution network.
Figure 4.2.1 Scheme Overview (Tonkin & Taylor, May 2013a)
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4.3 Dam Design
The proposed dam site is located on the upper Makaroro River approximately 1 km east of Wakarara
Road and 6.4 km northwest (upstream) of the confluence of the Makaroro and Waipawa Rivers. The
dam is located approximately 1 km from the Mohaka fault which also crosses the proposed dam
reservoir.
The proposed total water storage requirement of 90 million cubic metres at the site results in a dam
of approximately 83 metres height at the rivers deepest point. In order to provide a gross storage of
90 million cubic metres, the “Full Supply Level” of the reservoir is RL 469.5 m.
The Ruataniwha basin is located within an area subject to significant earthquake shaking and where
the geological formations are susceptible to deformation during such events. As a result, a number
of geological and geotechnical issues were identified during the feasibility studies that complicate
the design.
The dam is assessed as being within the High Potential Impact Category (PIC) for dams as defined by
NZSOLD19 (2000) Dam Safety Guidelines. This is the highest classification in the Guidelines and the
design of the proposed works is based on this rating. A High PIC requires the dam to have sufficient
spillway capacity to handle a flood between the 1 in 10,000 AEP Flood and the Probable Maximum
Flood (PMF). A PMF is assessed in a different way to lower frequency floods and it is not usually
described as having an AEP. It could, however, be said to have an infinite probability. The
Application Design adopts a Maximum Design Flood (MDF) equivalent to the PMF therefore meeting
NZSOLD guidelines.
Following a dam type option assessment that concentrated on the dam’s ability to accommodate
foundation deformation as a result of extreme seismic events, and the use of locally available
construction materials, a Concrete Faced Rockfill Dam (CFRD) was selected during the Feasibility
Stage as the recommended dam type for this site and this has been advanced as the “Application
Design”. Design arrangements for a CFRD type have been developed including zoning, spillways,
diversion tunnel, and intake towers, as described in more detail in Tonkin & Taylor (May 2013a).
19 New Zealand Society on Large Dams
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Table 4.3.1 - Key Dam Characteristics (Tonkin & Taylor, May 2013a)
Item Description
Dam type CFRD
Potential Impact category High
Spillway type Concrete lined primary spillway ogee weir (un-gated); Unlined auxiliary spillway for the 1 in 200 AEP plus climate change or larger events
Spillway capacity Probable Maximum Flood (approximately 752 cubic metres per second peak outflow
Full Supply Level (FSL) 469.5 metres Reduced level (height above datum)
Approximate dam storage volume at FSL 90,700,000 cubic metres
Approximate buffer storage for hydro generation 700,000 cubic metres corresponding to 0.2 metres water depth
Dam height Approximately 83 metres at river’s deepest point
Approximate reservoir area at FSL 3,700,000 square metres (370 hectares)
Dam crest level 475.5 metres Reduced level (plus 0.5m camber)
Dam crest width 8 metres
Dam crest length 505 metres
Dam batter slopes 1V:1.5H
4.4 Reservoir Operating Regime
The dam’s operating regime has been modelled to simulate the operation of the storage dam to
harvest, store and release river flows to meet irrigation demand and an environmental flow regime.
A number of “tranches” of water have been identified, which will be released from the dam within
the limits of available water in the following order of priority:
• A primary residual flow released from the dam of 1.23 cumecs equal to 90% of the 7-day
mean annual low flow (7-day MALF)
• A primary flushing flow allocation of 2.0 million cubic metres. (The size, timing and release
triggers for the primary flushing flows are described further in Tonkin & Taylor (May 2013a)
and in Aquanet (May 2013))
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• A primary irrigation volume of up to 95.8 million cubic metres, corresponding to a secure
primary irrigation volume of 91 million cubic metres delivered at the farm gate at full
Scheme uptake. The 95.8 million cubic metres accounts for the static storage of the dam and
an infill component
• A secondary flushing flow provision of 2.0 million cubic metres (The size, timing and release
triggers for the secondary flushing flows are described further in Tonkin & Taylor (May
2013a) and in Aquanet (May 2013))
• A secondary irrigation volume of up to 28 million m3. This volume is to be used to supply
water to existing irrigators and to a “spot market”. Provision for residual flow augmentation
to ensure downstream consent holders are not prejudiced by an increase in the number of
days minimum flow restrictions apply as a result of the RWSS is also included within this
tranche. (The size, timing and release triggers for these flow releases are described further in
the Proposed Conditions - Part D).
Reservoir storage modelling indicates that a reservoir with a gross capacity of 90 million cubic metres
can supply an irrigation volume of up to 95.8 million cubic metres per season, as required, with a
reliability of 11 out of 12 years, i.e. full supply security up to an 11 year return period drought. A
minor shortfall late in the irrigation season would occur once every 12 years on long term average.
4.5 Water Distribution System
The water distribution network commences with the upstream water intake structure on the
Waipawa River. This structure will collect the flows released from the proposed dam and distribute
the water via the primary and secondary distribution systems, primarily for use within the
production land use areas (Zones A to D and M) as shown on Figure 4.2.1. The primary distribution
system is intended to provide driving pressure for the secondary distribution system where possible,
although some areas will require pumping within the secondary pipeline network.
For Zones A – D, as shown on Figure 4.2.1, the primary distribution system headrace canal alignment
is constrained by the geography of the area (e.g. the foothills of the Ruahine Range) and the
elevation of the upstream water intake site (which acts as a control for the maximum elevation of
the primary distribution system). Following consideration of a number of options, an alignment has
been selected that balances the advantage of maintaining a high elevation to reduce pumping costs,
with an alignment that minimises the canal length and earthworks volumes.
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The primary distribution system for Zones A to D is a hybrid headrace canal and pipeline that
includes a combination of trapezoidal open channel where the design flows are greater than about
three cubic metres per second, and buried pipes for lesser flows.
The secondary distribution system is a network of pipes that have generally been located in road
reserves where possible, with a layout aimed to provide water to within two kilometres of all farm
gates within the defined production land use areas.
A tertiary pipe and pump system will be required for the on-farm supply. The required on farm
pressures have not been specifically considered in the primary and secondary distribution system
design outlined in Tonkin & Taylor (May 2013a) although the design presented in that document is
based on some positive pressure being available at the farm gate. Consequently, revision of aspects
of the water distribution network, particularly secondary distribution system components, may be
required when the specific locations and demand flow rates of individual users are defined. Further
optimisation and refined construction cost estimates for the developed alignment can then be
undertaken.
Outlets capable of energy dissipation are necessary because the system will otherwise cause stream
damage. This stream damage would be caused by the high pressures that may occur when the
Scheme has few users, such as during the initial phase after construction. Outlet structures are
located to suit environmental constraints including fish spawning and related issues as advised by
Cawthron20.
The design proposes outlet structures including three stilling basins and a plungepool. The stilling
basins have been designed following steps set out by the United States Bureau of Reclamation and
the plunge pool was designed following a design note produced by the United States Department of
Agriculture.
The water distribution network for Zone M (refer Figure 4.2.1) commences with the downstream
water intake structure on the Waipawa River, located immediately upstream of the confluence of
the Waipawa and Tukituki rivers. This will collect flows released from an outfall located adjacent to
the Mangaonuku Stream (within Zone A).
The existing Old Waipawa River Bed / Papanui Stream (“Papanui Stream”) is utilised to provide
primary distribution of irrigation water to Zone M. The stream would, in effect, function as an open
course headrace canal. Within specific sections of the Papanui Stream, particularly in the upper
20 See Aquatic Ecology assessment – Cawthron (May 2013)
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reaches where the old river bed is much wider, a channel will be established utilising a combination
of canal and stopbank construction within the old bed. In other sections, the existing stream profile
may be used. Engineered sections of the canal would incorporate specific design elements to
provide habit and enhance ecological values.
Irrigation water supplied by the RWS Scheme will be diverted from the Waipawa River and released
into the Papanui Stream in accordance with irrigation demand in Zone M. At peak demand,
irrigation flow has been estimated at 1.77 m3/s. Individual farm irrigation takes would be installed at
various locations along the length of the stream.
A residual flow of fifty litres per second will be supplied continuously to the Papanui Stream via a
diversion from the Waipawa River to support in-stream ecology except when the Papanui Stream
already has high flows. The distribution of irrigation water to Zone M is seen as having the potential
to facilitate a significant improvement to the environmental values of the Papanui Stream. The
concept HBRIC Ltd is pursuing is discussed in more detail in Section 5 of the Assessment of
Environmental Effects.
4.6 Hydroelectric Power Generation
Because the construction of the dam creates a large head difference on the river between the
upstream and downstream faces, it is possible to harness the energy from the controlled release of
water from the dam. A single power station at the foot of the dam is included in the Scheme design.
Preliminary optimisation of the capacity of the power plant, and costs against potential energy
output, has indicated an installed capacity of around 6.5 MW. The corresponding generation design
flow is 9.73 cubic metres per second, consisting of 1.23 cubic metres per second for the residual flow
turbine and 8.50 cubic metres per second for the main turbine, with both turbines housed in the
same power station. An operational buffer of 0.20 m dedicated to hydropower operation, over and
above the provision for irrigation storage, is included in the adopted Full Supply Level.
Power generated is proportional to the product of the generation flow and head, the latter of which
is given by the water level difference between the reservoir and the river downstream. The height of
the dam and thus the maximum generating head is more or less fixed. The energy output is thus
dependent on the size of the installed plant, specifically the maximum design generation flow and, to
a lesser extent, the buffering storage (0.2 m) provided within the reservoir. When the reservoir is full
or nearly full, this buffering storage allows partial capture of small floods and freshes (which would
otherwise be spilled) for generation.
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Because of its size, the power station will need to connect into Transpower’s grid exit point (GXP)
located at Ongaonga substation, about 21.5 km southeast of the Makaroro dam site via a 33kV line
which is a permitted activity under Central Hawke’s Bay District Plan rules.
4.7 Scheme Construction & Commissioning
A detailed Construction Environmental Management Plan (CEMP) will be finalised (based on the
draft submitted as Schedule Six in Part D – Proposed Conditions and will be required to be certified
by the relevant Consent Authorities prior to work commencing on site. The draft CEMP provides for
a number of Supplementary Construction Environmental Management Plans (SCEMPS) to be
prepared and certified governing specific elements of the Scheme. Those SCEMPS must meet the
objectives and performance standards specified in the draft CEMP.
The total construction time from contract award to Scheme completion of the “Application Design”
Dam structure is currently estimated at 54 months. The programme is based on getting 240
productive days per annum, the latter being derived from an assumed five productive days per week
for 48 weeks per annum (this allows for 2 weeks of Statutory holidays and two weeks of project shut
down for worker annual leave). It is expected that there will be an average of approximately 70
workers at the dam site over the construction programme.
Some activities such as the concrete face construction, once started, will continue 7 days per week,
24 hours per day, subject to compliance with resource consent conditions (for example as to
construction noise) and the CEMP.
Dam building by definition involves in-river construction works. It is generally desirable from a
constructability point of view to minimise the amount of work in the river whilst the river is flowing.
To achieve this, a temporary coffer dam will be constructed upstream of the main dam embankment
and the river diverted through a cutting and diversion tunnel through the terrace on the right bank.
Once built, this will enable the main dam to be constructed in the river without mobilising sediment.
River gravels will be utilised for concrete production. Extraction of river gravels is common in
Hawke's Bay. As such, the contractor will be required to comply with documents such as the HBRC's
Environmental Code of Practice for River Control and Drainage Works (June 2003). Methods such as
having designated river crossing locations and utilising out of river shoals will be used to minimise
disturbance of the river.
Hold points during reservoir filling are not normally required for CFRD constructions as the upstream
concrete face and the free draining rockfill ensure there is no build-up of pore pressure within the
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embankment. International practice is to place no restraint on filling rates and accordingly no hold
points or an additional low level outlet are therefore proposed for eventual dam filling.
In parallel to the construction of the dam the water distribution network broadly described above,
and in more detail in Tonkin & Taylor (May 2013), will be built.
4.8 Scheme Operation & Maintenance
A series of activities will need to be undertaken to ensure proper maintenance of the structures
forming part of the Scheme. Schedule Two of the Proposed Conditions govern operations and
maintenance activities.
Among other things those conditions ensure proper controls are in place to manage environmental
effects of maintenance activities, monitoring and management of sediment accumulation,
maintenance of flow level and measurement equipment and appropriate ongoing management of
dam safety issues.
The dam and distribution will be run remotely through the use of a SCADA/telemetry either with the
use of cell phone, landline or radio based systems.
The office for remote operating systems to be located will be a matter for HBRIC Ltd to determine. It
will either be an integral part of HBRC’s existing Hawke’s Bay office network, or devolved by way of
sub-contract to an entity with a different regional operating location.
Operations and maintenance will be undertaken by a suitable third party under a procurement
contract.
4.9 Potential Impacts from Operation
Potential impacts have been assessed and are more fully described in Tonkin &Taylor (May 2013a)
and the various effects assessment reports contained in later sections of this AEE.
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5 ZONE M HEADRACE CONCEPT
The report prepared by EMS (EMS, May 2013a) presents and assesses an option to utilise the
existing Old Waipawa River Bed and the Papanui Stream as the primary distribution mechanism for
Zone M of the proposed RWSS.
The dual objective of the proposal is to provide for the efficient delivery of irrigation water to Zone
M and enhance the in-stream and riparian ecological values of the Old Waipawa River Bed and the
Papanui Stream.
Old Waipawa River Bed and Papanui Stream are separate but connected waterways. In the 1880’s,
the Waipawa River was diverted to join the Tukituki River at its current confluence. The Papanui
Stream, initially fed by groundwater and supplemented by run-off from surrounding land, flows
down the path of the Old Waipawa River Bed in a north north-easterly direction, through the area
defined as Zone M.
Sheep and beef and arable farming make up over 90% of land use within the Papanui catchment.
An ecological assessment of the Papanui Stream has shown that it is currently in poor ecological
condition. Extensive macrophyte growth has been recorded. The stream has little shading, and
suffers from generally unrestricted stock access.
A cultural impact assessment has been prepared by Te Taiwhenua ō Tamatea that identifies historic
and cultural values associated with the area. The assessment notes that Tangata Whenua generally
support the ecological restoration proposed, subject to ongoing consultation, and engineering works
avoiding wahi tapu sites. There are few other social or recreational values present given the current
degraded state of the waterways.
The stream bed is held in private ownership for much of its length. It is likely that the proposal would
affect up to 98 parcels of land, representing around 40 different landowners.
The current Old Waipawa River Bed is characterised by a wider, steeper upper section, and a
narrower, flatter lower section where it becomes the Papanui Stream. Some works would be
required to form an effective canal system. A conceptual cross section for the proposal has been
developed providing design criteria to meet ecological and engineering perspectives.
Hydrodynamic modelling has shown that it is feasible to construct a channel as presented in the
conceptual cross-section contained within the report, and that such a channel can effectively convey
the anticipated full irrigation demand of approximately 1.77 m3/s to Zone M plus a 50 litres/second
residual flow. Further work is required to determine the extent of subsurface infiltration that may
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occur, but any excessive infiltration can be addressed by channel sealing and provision for this has
been made in the RWSS consent applications.
This concept has been shown to provide an effective means of distributing irrigation water to Zone
M at lower cost. It also presents opportunities for significant ecological benefits for the Old Waipawa
River Bed, the Papanui Stream, and the wider Tukituki catchment. This supports the direction
promoted by the Change 6. For example, phosphorus loading can be reduced through riparian
filtering and stock exclusion, and the periphyton and macrophyte growth are expected to be reduced
through stream shading from riparian planting.
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6 ENVIRONMENTAL FLOW OPTIMISATION
6.1 Introduction and Basis for Assessment
The way in which flows are managed in the Tukituki catchment is a key issue for the RWSS. The
Scheme both creates risks of adverse environmental effects which must be managed, and provides
opportunities for environmental benefits which would not otherwise be achieved.
As discussed in previous sections, the Tukituki River and its catchment support a number of values,
including ecological (e.g. habitat for indigenous species), cultural e.g. (Mauri of the river and eel
fishery), recreational (e.g. amenity, contact recreation and trout fishery) and socio-economic values
(e.g. production land, industrial and public water supply). The report noted that these values are
however currently limited by extended periods of low summer flows and excessive filamentous algae
growth, particularly in the lower Tukituki River (“lower Tukituki corridor”). Summer low flows occur
naturally in the Tukituki River, but their frequency, severity and duration are currently compounded
by surface and groundwater abstraction for irrigation, industrial use and community water supply.
Excessive periphyton growth is a result of a combination of nutrient enrichment and the river’s
natural characteristics, in particular the extended periods of low flows. Again, this issue is likely
compounded by surface and groundwater abstraction.
Surface and groundwater abstraction (primarily used for irrigation) in the Tukituki catchment has
increased substantially over the last decade. This has contributed to the over-allocation of surface
water in the Tukituki catchment, based on current allocation limits. If water allocation limits are
altered by provision of increased regulatory minimum flows, as is proposed in the Tukituki Proposed
Change 6 to provide for improved ecological, recreational and cultural outcomes, the result would be
a significantly reduced security of supply for existing irrigators with a consequential material
economic impact on them, and reduced regional economic output.
6.2 Assessment Undertaken
A report co-ordinated by Aquanet Consulting Ltd (Aquanet, May 2013) assesses flow optimisation in
greater detail. The aim of the Environmental Flow Optimisation study was to explore options
available to the RWSS to provide additional water for irrigation or environmental purposes, over and
above, but without compromising, the assumed primary irrigation and environmental flow
provisions described in the Feasibility Project Description (Tonkin & Taylor, 2012).
The study was undertaken in several phases, including an initial assessment of opportunities for the
RWSS to provide additional water, an assessment of possible environmental use of that water,
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followed by a modelling exercise using the GoldSim modelling platform, which incorporates the
major flow components of the RWSS Scheme into one integrated dynamic model.
This report also provides an assessment of the RWSS Scheme’s predicted effects on, or benefits to,
river flows in the Waipawa and Tukituki rivers under different scenarios. The potential effects and
benefits of the proposed environmental flow “package(s)” on aquatic ecology are assessed in the
Aquatic Ecology Assessment prepared by the Cawthron Institute (Cawthron, May 2013).
Three areas for improved environmental flow have been identified as part of the preliminary
assessment of “opportunities”:
• The volume of water provisioned for irrigation in the feasibility study (95.8 Mm3) was based
on a full uptake of the RWSS water, with a nominal 1 in 20 year security of supply. This
means that, assuming full uptake of the water offered by the RWSS for irrigation, the live
storage of the dam would be completely used up (emptied) with resulting cessation of
supply to irrigators in once every 20 years on a long-term average. This also means that the
volume of water available from RWSS will exceed the water demand in most non-drought
years. This water can either be retained in the dam or released from the dam for other
purposes, such as additional irrigation, and/or environmental flows. A preliminary
assessment undertaken by Tonkin & Taylor identified that at least approximately 3.5 Mm3
will be available 9 years out of 10, with an additional 2.1 Mm3 available 6 years out of 7 (or
an additional 4.4 Mm3 available 4 years out of 5), and this assuming full uptake21
• Full uptake of the Scheme’s irrigation water is not expected to occur from the start of the
Scheme. Recent provisional estimates of the likely level of RWSS water uptake indicate that
full uptake is likely to occur 8 to 14 years after the Scheme is operational, depending on
uptake by existing irrigators (Castalia, 2012). “Excess” water will be available until the uptake
is full, some of which may be able to be used for environmental purposes
• The “sedimentation storage” allowance of 4 Mm3 is to provide for the loss of storage volume
due to sedimentation associated with the input of material from the upstream catchment.
Until this volume is taken up by sediment, there is an opportunity to utilise this volume of
water for environmental purposes.
It was identified that of the three areas identified above, only one (the first) would be potentially
available during the whole life of the Scheme, while the other two may only be temporary. For this
21 As discussed in Section 4.6 recent modelling indicates that the reliability based on the historic flow record is 11 out of 12 years full supply reliability with some minor gaps in supply availability late in the irrigation season in the twelfth year.
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reason, the assessment conducted in this report primarily focused on the first opportunity, whilst
recognising the additional potential associated with the second and third opportunities during the
early years of the Scheme.
With the key environmental issues in mind, two areas for potential improvement were identified for
the purpose of this study:
• Supplementing/augmenting river flow at times when it would otherwise have dropped to
very low levels, particularly during summer
• Increasing the size, duration or frequency of flushing flows released from the dam, and/or
improving the timing of their release, to optimise environmental benefit associated with
reducing/removing nuisance periphyton with a particular focus on the lower Tukituki River.
The potential benefits of different levels of low flow supplementation and flushing flows are
assessed in the report, as well as the volumes of water required to implement them. This analysis
relied heavily on hydrological data and modelling provided by the Hawke’s Bay Regional Council’s
Environmental Science (Hydrology) and Engineering departments.
The Environmental Flow Optimisation report also incorporates outputs from a modelling exercise
undertaken by Golder Associates (NZ) Limited (Golder) using the GoldSim modelling platform. With
specific regard to this report, the key objectives of the GoldSim modelling were:
• To assess the ability of the dam to release the significantly increased flushing flows
recommended in this report
• To assess the likely effects of the Scheme on downstream river flows under different
“uptake” scenarios (referring here to “uptake” of Scheme water by existing water
abstractors in replacement of all or part of their current takes). This meant in particular
assessing the likely outcomes of “intermediary” scenarios assuming various levels of uptake
by existing groundwater abstractors
• To provide a preliminary assessment of the potential benefits of increased drainage from
newly irrigated land (“irrigation water return”) on river flows. The methodology used for this
preliminary assessment is presented in Appendix C of Aquanet (May 2013).
6.3 Results of Assessment
6.3.1 Flushing Flows
Flushing flows of 50 m3/s as measured in the Tukituki River at Red Bridge would ideally be generated
in order to provide significant bed sediment mobilisation and attached periphyton removal,
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however, there is strong evidential basis to suggest that flows much smaller than 50 m3/s, in the
order of 23 to 34 m3/s (as measured at Red Bridge) are likely to provide significant benefits – if not
removing the whole biomass, at least providing considerable relief and public health risk avoidance
by removing the drifting/detaching algae and cyanobacteria.
Hydrodynamic modelling (MIKE11) indicates that the release of flows of 30 m3/s for 9 hours or 25
m3/s for 11 hours were likely to result in flushing flows within the 23 to 34 m3/s range along the
lower Tukituki corridor down to Red Bridge, even under otherwise low river flow conditions.
Modelling also shows that the environmental benefits brought by these flushing flows can be further
enhanced by managing the timing of their release to “piggy-back” on natural minor fresh events
(freshets) which by themselves would have had limited benefits in terms of periphyton removal.
The release of up to four flushing flows of up to 1 Mm3 each per irrigation season was modelled in
GoldSim, using triggers and rules designed to “interrupt” periphyton accrual periods when they
reach 30 days during the critical December to March period and encouraging piggy-backing on
natural fresh events. Results show that the flushing flows were able to be supplied every year of the
36 year modelling period, up to the specified four flushing events. Piggy-backing on natural freshets
allows both an increase in the size of the actual flushing flows and a reduction in the overall volume
of water required to deliver the flushing flows.
6.3.2 Effects on Downstream Low Flows and Low Flow Supplementation
Results indicate that the Scheme is likely to result in significant improvement of the extreme low
flows (minimum flow and Q99) in both the Waipawa and lower Tukituki Rivers under all scenarios
considered. However, the Scheme may result in a reduction of MALF and an increase in the number
of days below the proposed minimum flow if current water takes continue to their current level.
The Scheme is also predicted to result in benefits to low flows at Red Bridge if at least 30 % of
groundwater takes (or a mix of surface and groundwater takes) stop operating in the future
(presumably to utilise water provided by the Scheme). However, modelling results indicate that a
higher proportion of current takes (in the order of 80% of current groundwater takes) being
discontinued may be required in order to avoid residual negative effects on low flows at the
Waipawa River at RDS. These results suggest that some low flow supplementation targeted at
compensating for effects on low flows at RDS may be required depending on the level of uptake by
current irrigators upstream or upgradient of that site.
The above conclusions do not take into account the potential benefits of increased drainage
associated with additional irrigation provided by the Scheme. The preliminary assessment
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undertaken using the GoldSim model indicates that if this effect was fully realised, the
implementation of the Scheme would be predicted to result in significant improvement of low flows
(using MALF and the mean number of days below minimum flow as key indicators) under all
scenarios considered at Red Bridge. Residual effects may however still occur at RDS, which
reinforces the conclusion that direct mitigation may be required to mitigate potential effects at RDS.
It is also noted that the release of irrigation water to service Zone M may to some extent, alleviate
the need for low flow supplementation at that site.
6.4 Report Recommendations
Four key recommendations have been formulated in this report:
Recommendation 1
That flushing flows as described in the Project Description (Tonkin & Taylor, May 2013a) be
included in the set of proposed consent conditions.
As indicated throughout the Environmental Flow Optimisation Report, there is strong evidential basis
to suggest that the release of “augmented” flushing flows as described in the report is likely to
provide significant environmental benefits, particularly during the extended periods of summer low
flows, when other means of controlling periphyton growth (such as nutrient management) are of
reduced effectiveness. Being able to “interrupt” all periphyton accrual periods in the lower Tukituki
River at Red Bridge before they exceed 30 days during the critical summer period provides an
opportunity that would not otherwise exist to contribute to progress towards Change 6’s periphyton
biomass targets.
Modelling indicates that the water volumes required for both the primary and secondary flushing
flows can be supplied by the dam every year. On this basis, it appears that the proposed consent
conditions do not need to differentiate between primary and secondary flushing flows, and it is
recommended that the proposed consent conditions require the release up to four flushing flows
every year, based on the date and river flow triggers defined in the report these flushing flows can
be supplied by the dam.
It is also noted that the ability of the dam to deliver instantaneous flows of 30 m3/s may be limited
when water levels in the dam reach very low levels. It is suggested that in this instance, the duration
of the flushing flows should be increased proportionally to the reduction in instantaneous flows, and
that, for example flushing flows of 25 m3/s for 11 hours would be likely to also achieve significant
benefits. It is recommended that consent conditions allow for this level of flexibility.
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Recommendation 2
That further modelling of irrigation water return be undertaken.
The increased drainage associated with a greater area of land is expected to result in an increase in
the return of groundwater to surface water. Preliminary assessment undertaken as part of the
GoldSim modelling has indicated that this positive effect may be significant when considering the
low river flow range. It is acknowledged that this is only a preliminary assessment based on using
average values derived from a simple water balance estimate, and it is recommended that this
potential effect be more fully assessed.
Recommendation 3
That modelling be re-run if/when uptake is known
The modelling has thus far been undertaken on the basis of blanket proportional reduction of all
current takes. In reality, individual takes may be stopped in the future whilst others will continue.
The outcomes in terms of river flows may depend on the location and characteristics of each
individual take being “replaced”. Such a level of detail cannot of course be modelled at present as it
would be speculative to pre-determine which takes may or may not be “replaced”. It is our
understanding that the Scheme’s commercial team will be entering in discussions with current water
abstractors over the next few months. If and when formal agreements to supply water are finalised,
it is suggested that it would be useful to undertake modelling on the basis of these more certain
“uptake” data.
The uptake of RWSS water by existing or new irrigators within Zone M is also currently unknown,
but, as noted above, the supply of water to Zone M may alleviate to some extent the need to
undertake low flow supplementation at RDS (for example low flow supplementation may only be
required when water is not being supplied to Zone M). Again it is suggested that this aspect be
incorporated in future modelling once uptake within Zone M is known.
Recommendation 4
That provision be made to mitigate any actual effects of the RWSS on river low flows at RDS
and/or at Red Bridge by targeted low flow supplementation.
As explained in the Environmental Flow Optimisation Report, the implementation of the RWSS may,
under some scenarios, result in negative effects on low flows, both from an ecological (as indicated
by decreases in MALF) and resource use (as indicated by the number of days below PRMF) point of
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views. These effects may, or may not eventuate, depending primarily on the level of uptake by
current water abstractors and the potential effects of the irrigation water “return”.
As per recommendations 2 and 3 above, it is recommended that further assessment be undertaken,
before and during the implementation of the Scheme, in particular to incorporate actual levels of
Scheme uptake when these become more certain.
It is also recommended that the Scheme release additional water as required to offset the modelled
effects of the dam’s operation on the number of days below the proposed minimum flow and give
further consideration to addressing the adverse effects on MALF as shown by modelling results at
the time.
However, the uncertainties inherent in modelling low river flows need to be acknowledged. This is
particularly the case at RDS where historical low flow data appears to have a greater level of
uncertainty as pointed out in HBRC Science (May 2013a). Whilst the above approach based on
modelled effects is considered suitable (and is recommended) at Red Bridge, a more certain
approach, not based on modelling, may be more appropriate at RDS. A relatively simple and
pragmatic way to ensure that the Scheme does not result in an increase in the number of days below
the proposed minimum flows at RDS would be a consent condition requiring the Scheme to match,
within given bounds, the natural inflows it receives when the flow at RDS is below, or is dropping to
levels very close to, the proposed minimum flows.
In order to maintain the proposed residual flow at all times, the condition should be worded so that
the rate of water discharge from the dam at those times is the larger of 1.23 m3/s and the inflow to
the dam measured at the time.
It is also recommended that an upper bound be defined. Given the flow travel times to the lower
catchment (approximately 12-18 hours from the dam to RDS and 30 hours to Red Bridge), situations
may arise where a significant rainfall occurs in the hills, but the flow at RDS is still close to or below
the proposed minimum flow. In these situations, there would be significant inflows to the dam, and
also from the upper parts of the Tukituki and Waipawa River catchments. If the flow release from the
dam was to fully match its inflow, the Scheme would have to release a significant flow (potentially
several m3/s) for a period of up to 18 hours, in spite of that water only reaching the lower catchment
at the same time as the water from the rest of the upper catchment. In effect that water would have
served no purpose in terms of supplementing low flows at RDS or Red Bridge, but with consequential
loss of storage. An upper bound of 1.8 m3/s, corresponding to approximately 130% of MALF at the
toe of the dam is suggested.
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7 IRRIGATION ENVIRONMENTAL MANAGEMENT PLAN
As with water flows, the RWSS both creates risks of adverse environmental effects consequential on
the use of the irrigation water to enable intensification of production land uses which must be
managed, and opportunities for environmental benefits. How those risk and opportunities are
managed is an important part of the integrated approach to the wider HBRC strategy for the Tukituki
catchment described in the Preamble to this AEE. HBRIC Ltd intends that the Scheme and its
environmental objectives will be a key cornerstone of that strategy.
Much of this will be achieved through the implementation of the Irrigation Environmental
Management Plan (IEMP) which is the subject of a detailed document that forms part of the
applications - see Irrigation Environmental Management Plan - HBRIC (May2013e). This document is
presented as a draft and the proposed conditions in Part D provide for the draft to be updated and
finalised once final details of the conditions and Scheme configuration are confirmed.
The IEMP describes how irrigation users who join the Scheme will be required to interact with the
HBRC’s water quality regime in the Tukituki Catchment. It sets out planned monitoring and
mitigation steps required by HBRIC Ltd as both the resource consent holder and a contractual party
to Farm User Agreements, and the Scheme’s users, to jointly manage and control discharges to the
environment. Compliance and enforcement provisions are also presented.
The IEMP details how sub-catchments posing a risk of exceedence of Change 6 nitrate-nitrogen limits
or where there is a material risk of increases in phosphorus reaching waterways will be managed
pro-actively – irrigators will only be supplied with water from the Scheme if assessment of their
proposed land uses indicates those limits will not be compromised. Where necessary, appropriate
mitigation measures will be required to ensure nitrate and phosphorus outputs from individual farms
are limited. Those measures may include, where necessary, constraints on the range of land uses
that establish using water from RWSS in high risk areas through contractual means. This will ensure
the relevant consent conditions relating to managing the whole Scheme within limits are always met
by the consent holder.
Key nutrient, soil, waterway and wetland management targets to be incorporated in irrigation users’
environmental management plans are set out. The independent audit procedures, triggers and
timelines for remedial actions are also described in the IEMP.
The process of developing the water quality and management disciplines described in HBRIC (May
2013e) has been strongly consultative and will continue to be so through a proposed Scheme
Operations Liaison Group that is representative of the wider community.
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A critical component of the IEMP is the implementation of Farm Environmental Management Plans
which provides both a positive solution and a process by which intended environmental targets and
limits described more fully in HBRIC (May 2013e) can be implemented and enforced for the many
thousands of hectares that will be irrigated by landowners using the Scheme. A reliable water supply
is a powerful incentive and contractual tool for HBRIC Ltd and land users to work jointly to modify
existing farm practices, where necessary, to manage both water quality and quantity within specified
limits. It is therefore a condition of water supply from the Scheme that each user enters into a
FEMP.
The FEMP will (inter alia) set out policies, practices and actions that will collectively address (where
relevant) the following areas of activity:
• Nutrient management
• Irrigation management
• Soils management
• Wetlands and riparian management
• Collected animal effluent management
• Livestock management
A key requirement of the FEMP process will be nutrient budgets for each property supplied by the
Scheme. All properties will be required to supply a nutrient budget and in some sensitive areas,
under the provisions of the IEMP a draft FEMP will also be required prior to a water supply contract
being finalised.
Both the FEMP and the nutrient budget will be required to be updated regularly and will be subject
to periodic independent audit.
If an audit report indicates non-compliance with the conditions of water supply that are incorporated
in the FEMP, HBRIC Ltd (as consent holder) will give notice to the land owners that unless remedial
actions are taken to ensure conditions of supply are met before the commencement of the next
irrigating season, water will not be supplied to that property until such time as the conditions are
met.
Under the IEMP, HBRIC Ltd intends that it will also provide further information on farming practices
for irrigated and non-irrigated land to assess the effectiveness of FEMPs and, more generally, how
information might be utilised to shape wider Tukituki Catchment improvement initiatives.
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The aims and objectives of the IEMP are captured within proposed general conditions that form part
of the application and which are described more fully in Part D – Proposed Conditions.
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8 INTEGRATED MITIGATION AND OFFSET APPROACH
A range of studies have been completed in order to quantify the potential effects of the proposed
RWSS on the environment and communities in Central Hawke’s Bay as presented in this AEE.
Through their assessments, a range of environmental effects study authors have taken account of
avoidance, remediation, and mitigation proposals built into the scheme design, and where
necessary, have made recommendations for additional actions avoiding, remedying or mitigating
potential effects.
The separate report Integrated Mitigation and Offset Approach (HBRIC, May 2013f) sets out the
proposed integrated mitigation and offset approach designed to address the residual biophysical
effects (e.g. effects on terrestrial and aquatic ecology) around the dam/reservoir area and
downstream to the Upstream Water Intake site, that are not practicably able to be otherwise
avoided, remedied, or mitigated directly or entirely. Flooding of the Makaroro River bed upstream
of the dam will also have a permanent effect on recreation facilities and the historic Yeoman Mill site
at the end of Wakarara Road. As such, the effects on recreation, landscape, heritage and cultural
values have also been considered.
Effects addressed in HBRIC (May 2013f) include:
• Loss of significant terrestrial indigenous vegetation. This is the area of ecologically significant
indigenous vegetation covered by the dam and reservoir footprint, which is calculated to be
106.10 ha
• Edge effects. The assumed detectable edge effects area which would be adversely affected
is 10 ha
• Braided river habitat. The area of braided river habitat (gravel river bed) lost under the
reservoir and dam footprint is calculated to be 73.97 ha
• Wetland habitat. The area of ecologically significant wetland and seep zone habitat which
would be lost is estimated to be 5.11 ha
• Loss of habitat for Threatened and At Risk Species. Loss of significant habitat for seven At
Risk and Threatened terrestrial fauna and flora species would result as a consequence of the
dam and reservoir, equating to 185.18 ha
• Loss of habitat for some indigenous aquatic species that are unlikely to find the reservoir
habitat suitable for them
• Loss of trout spawning habitat in the areas occupied by the dam and reservoir
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• Loss of the established walking track from the end of Wakarara Road, across the Makaroro
River, to the DOC tracks extending throughout the Ruahine Forest Park
• Loss of the informal camping area located on the Wilson’s property
• Inundation of any remaining infrastructure associated with the historic mill site located at
the end of Wakarara Road
• Loss of fish passage beyond the proposed dam to the upper bounds of the Makaroro River
and Dutch Creek
• Changes to the flow regime of the Makaroro and Waipawa Rivers; in particular, upstream of
Caldwell Road with a consequent adverse effect on the invertebrate population and trout
spawning in those reaches
• Potential increase in DRP inputs to the rivers as a result of land use intensification and an
associated increase in periphyton growth.
The mitigation/offset projects proposed were developed via the following steps:
1. Individual Assessment of Environmental Effects reports were completed by
consultant/HBRIC teams for the studies listed in Section 1.2 of the HRBIC (May 2013f) report.
This included assessing the proposed Scheme against relevant planning provisions,
quantifying potential effects, recommending actions to avoid, remedy or mitigate those
effects, and where residual adverse effects were identified, highlighting these in the study
reports for follow up by the HBRIC project team. With respect to the terrestrial ecology
study, this also included an assessment against the BBOP Principles22 and proposed National
Policy Statement on Indigenous Biodiversity
2. The issues, constraints and opportunities identified through the AEE reports were explored
during a Design Workshop held on 6 March 2012 and attended by key consultant teams and
representatives of DOC and Mana Whenua
3. A meeting with landowners was held on 30 March 2012 to share information about the
Scheme and flag the issues, constraints and opportunities for follow-up with landowners on
a one-on-one basis
4. Individual study findings and recommendations were presented to the Ruataniwha
Stakeholder Group, including the measures proposed to mitigate or offset potential effects
where concepts were adequately advanced
22 Business and Biodiversity Offsets Programme Principles - the preferred approach to biodiversity mitigation by
Department of Conservation
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5. Consideration was given to the Tukituki Cultural Values and Uses report – Taiwhenua ō
Tamatea & Taiwhenua ō Heretaunga (June 2012), which makes recommendations regarding
the maintenance and restoration of Mauri to provide appropriate responses through a
mitigation and offset programme that ensures the Scheme recognises appropriate cultural
values (including native fish and water quality benefits)
6. Presentation of the draft “Proposed Integrated Mitigation and Offset Approach” report to
the Ruataniwha Stakeholder Group during their 27 July 2012 meeting
7. Refinement (including costing) and documentation of the mitigation/offset package
proposed, taking into account written feedback received from stakeholders after the 27 July
2012 meeting
8. Further project development via a workshop with key stakeholders, held on 16 January 2013
9. The report was presented to the Mana Whenua Working Party on 8 February 2013 for
discussion and feedback
10. From subsequent discussions with the Mana Whenua Working Party regarding the on-going
kaitiaki role of Mana Whenua HBRIC Ltd decided that it would be appropriate to offer a
Mana Whenua entity the first right to tender for the contract to implement the mitigation
and offset projects
11. A joint key stakeholder / Mana Whenua Working Party workshop was held on 17 April 2013
to discuss the proposal developed in Step 10 and the mechanisms to achieve this including
conditions etc. It was also agreed at this meeting that Project E would be added to the
proposed mitigation and offset approach. Project E concerns the restoration of the old bed
of the Waipawa River and the Papanui Stream as part of the primary distribution of irrigation
water to Zone M of the Scheme
12. Recent (May 2013) reallocation of funding between components of Project C (as described
below) to enable greater priority to be given to downstream eel trap and transfer over
recommended bat survey and targeted habitat enhancement, with final decisions over these
funding reallocations to be made on future implementation over a 30 year timeframe.
Five projects are proposed in response to the potential effects outlined above and discussed in detail
in the HBRIC (May 2013f) report. Projects A to C and E set out biodiversity restoration and
enhancement strategies proposed to address residual effects on both terrestrial and aquatic
biodiversity. These projects also address effects on recreation, cultural and heritage values
associated with the Wakarara Road-end area. Project D provides an additional offset for adverse
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effects of the proposed Scheme on phosphorus inputs to the streams and the availability and quality
of in-stream habitat for trout spawning, native fish and invertebrates.
The estimated total cost provision for offset mitigation requirements over a 30 year period equates
to approximately $8.7 million, with the most significant costs incurred in the first ten years of the
project.
Acknowledging that the success of the projects proposed depends on the long-term, sustained
agreement and effort of a number of key stakeholders, it is proposed that a Ruataniwha Biodiversity
Advisory Board be established prior to construction of the dam. The Advisory Board’s primary role
would be to receive the Integrated Mitigation Offset Programme Annual Report required in the
proposed conditions of resource consents for the Scheme, to guide the prioritisation of activities,
and to ensure delivery of the proposed projects within the agreed timeframes.
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9 RMA ACT FRAMEWORK
9.1 Introduction
This section identifies the relevant framework under the RMA for assessing the RWSS.
The Environmental Management Services Limited report, Ruataniwha Water Storage Scheme
Planning Assessment (EMS, May 2013b) (referred to as the Planning Assessment) identifies the
resource consents that are required for the RWSS under the RMA. It also presents an analysis of the
RWSS in relation to the relevant policy framework within which HBRIC Ltd’s resource consent
applications for the proposal will be assessed and determined. The following sets out the key
aspects of the Planning Assessment.
9.2 District Councils
The activities associated with the RWSS are located in the Central Hawke’s Bay District and the
Hastings District. Figure 3.2.1 in Section 3 of this document shows the location of the key activities
associated with the RWSS in relation to the boundary between the two districts.
Under the RMA CHBDC and HDC have jurisdiction for the control of land uses within the Central
Hawke’s Bay and Hastings Districts respectively.
The following sections summarise the activities associated with the RWSS within each district and
identify the land use status of those activities as determined by the relevant district plans prepared
under the RMA.
9.2.1 RMA Status of Activities within the Central Hawke’s Bay District
The activities associated with the RWSS within the Central Hawke’s Bay District (within the
jurisdiction of the CHBDC) are as follows:
• The proposed Makaroro Dam (and associated structures) and the majority of the reservoir;
• Electricity generation and transmission (and associated infrastructure)
• Water distribution network infrastructure for the supply of water (primarily for irrigation
purposes), including intake and outfall structures, open headrace canals and pipeline
• The irrigation of production land areas facilitating farming activities undertaken by third
parties (including any changes or intensification of land use)
• Land disturbance/earthworks, vegetation removal, quarrying, concrete batching, the storage
and use of hazardous substances, the creation of access roads and tracks, riparian planting,
and other works and activities associated with the construction of the above.
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The RMA status of the above land use activities within the Central Hawke’s Bay District is determined
by reference to the Central Hawke’s Bay District Plan (CHBDP) that was made operative on 1 May
2003. There are no proposed District Plan Changes that are relevant to the proposed activities.
A detailed analysis of the aspects of the RWSS within the Central Hawke’s Bay District has been
undertaken in the Planning Assessment in relation to the CHBDP. The results of that analysis are
summarised in Table 9.3.1 below.
Table 9.2.1: RMA Activity Status of Activities under the Central Hawke’s Bay District Plan
Activity Relevant District Plan Rule(s) Activity Status
• Construction, operation, and maintenance of the proposed water storage dam on the Makaroro River.
4.8.3(f) Discretionary
• Reservoir. 4.8.3(f) Discretionary
• Electricity generation. 4.8.3(f) Discretionary
• Water intake structures. 10.4.3(b)
10.5.7 Discretionary
• Community irrigation and stock water races, public open drains and channels (where above ground).23
10.4.3(b) Discretionary
• Underground pipe networks for the conveyance of water, and any ancillary equipment including pump stations.
10.4.1(g)
Permitted
• Water outfall structure.24 10.4.3(i) Discretionary
• Transmission of electricity:
o Lines for conveying electricity at a voltage up to and including 110KV with a capacity up to and including 100MVA per circuit;
o Poles, insulator, casing, minor fixture, or other equipment or material used or intended to be used for supporting, enclosing, surrounding, or protecting any line, or part of line for conveying electricity (as above):
restricted to a maximum height of 25m in the Rural Zone;
10.4.1(a)(i)
10.4.1(a)(iii)
Permitted
Permitted
23 The open canal headraces forming part of the RWSS fall within the ambit of Rule 10.4.1(i) being a permitted activity, but
become a discretionary activity under Rule 10.4.3(b) on the basis that they are ‘buildings’ and exceed the limit in relation to gross floor area. The RWSS is a Community Irrigation Scheme under the provisions of Change 6 to the RRMP (discussed later in this report). Any alternative interpretation in relation to whether the headrace is a ‘community’ facility or not is of no consequence in terms of the status of the activity as it would still be a discretionary activity under Rule 10.4.3(i) of the CHBDP.
24 Water intake structures and water outfall structures fall within the ambit of different rules (both resulting in discretionary activity status) on the basis that the former is provided for as a permitted activity but becomes a discretionary activity due to a breach of the performance standard relating to coverage while the latter is not provided for as a permitted activity and is caught by Rule 10.4.3(i) being a ‘catch-all’ rule.
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o Transformers used for conveying electricity at a voltage up to and including 110KV with a capacity up to and including 100 MVA, containing more than 1,000 litres of oil:
restricted to a maximum height of 25m in the Rural Zone;
13.5.2
Discretionary
• Storage and use of hazardous substances. 13.5.2 Discretionary
• Telecommunications and telemetry facilities. 10.4.1(d) Permitted
• Operation, maintenance and minor upgrading25 of utilities. 10.4.1(m) Permitted
• Earthworks. 3.6.1 Permitted
• Farming activities undertaken by third parties. 4.8.1 Permitted
The activities identified as permitted activities in Table 9.2.1 above are subject to compliance with
the Performance Standards set out in Section 4.9 in relation to the Rural Zone and Section 10.5 of
the CHBDP in relation to Utilities as applicable.
Summary of Consent Requirements:
• A discretionary activity resource consent is required under the rules of the CHBDP26 for the following
aspects of the RWSS:
Construction, operation, and maintenance of the proposed water storage dam and associated
reservoir on the Makaroro River including the generation of electricity and an associated transformer;
Water intake structures on the Waipawa River;
Water distribution headrace (above ground canal component);
Water outfall structures on the Mangaonuku Stream and the Kahahakuri Stream;
Storage and use of hazardous substances; and
All associated works, structures and ancillary activities (including the modification of Areas of
Significant Nature Conservation Value and riparian planting) associated with the above activities.
• All other aspects of the RWSS are either permitted activities under the rules of the CHBDP or, as discussed
below, will be the subject of resource consent applications at a later date.
25 Minor upgrading does not include any increase in the voltage of a line; or an increase in the gross floor area or height of a
building for utility activities (unless that increase is for any of the purposes set out in Rule 10.4.1(m)(i) to (vi)). 26 Except to the extent such activities are the subject of a designation (discussed later in this AEE).
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9.2.2 RMA Status of Activities within the Hastings District
The aspects of the RWSS within the Hastings District (within the jurisdiction of HDC) are:
• The upstream part of the reservoir formed by the construction of the Makaroro Dam (the
Dam itself being within the Central Hawke’s Bay District)
• Pipelines for the supply of water (primarily for irrigation purposes) in the northern parts of
Zones A and M
• Land disturbance/earthworks (including a borrow area), vegetation removal, quarrying, the
creation of access roads and tracks, riparian planting, and other works and activities
associated with the construction of the above
• The irrigation of land in the northern parts of Zones A and M facilitating farming activities
undertaken by third parties (including any changes or intensification of land use).
The RMA status of above land uses within the Hastings District is determined by reference to the
Hastings District Plan (HDP) that was made operative on 10 June 2003. There are no proposed
District Plan Changes that are relevant to the proposed activities.
A detailed analysis of the aspects of the RWSS within the Hastings District has been undertaken in
the Planning Assessment in relation to the HDP. The results of that analysis are summarised in Table
9.4.1 below.
Table 9.2.2: RMA Activity Status of Activities under the Hastings District Plan
Activity Relevant District Plan Rule(s)
Activity Status
• Reservoir. 13.3.7.3 Restricted Discretionary
• Underground pipe networks for the conveyance of water.
13.3.7.1(B) Permitted
• Earthworks. 13.4.7.2 Restricted Discretionary
• Mining (aggregate extraction). 13.2.7.3 Discretionary
• Farming activities undertaken by third parties. 5.7.1 Permitted
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Summary of Consent Requirements:
• Applying the ‘bundling’ approach, a discretionary activity resource consent is required under the rules of
the Hastings District Plan for the following aspects of the RWSS:
The formation of the reservoir as a result of the construction of the Makaroro Dam (the latter being
within the Central Hawke’s Bay District) including associated earthworks and vegetation clearance,
the construction of roads and tracks, and riparian planting.
Mining aggregate associated with a borrow area.
• All other aspects of the RWSS are either permitted activities under the rules of the HDP or, as discussed
below, will be the subject of resource consent applications at a later date.
9.3 Hawke’s Bay Regional Council
The activities associated with the RWSS are located entirely within the Hawke’s Bay Region.
Under the RMA, HBRC has jurisdiction for the management of the taking of water and the discharge
of water and contaminants to water, land and air within the Hawke’s Bay Region. HBRC also controls
land uses such as earthworks, the clearance of vegetation, the erection of structures in, on, under or
over the beds of rivers, and the disturbance of river beds.
The RMA status of the activities associated with the RWSS within HBRC’s jurisdiction is determined
by reference to the RRMP made operative in August 2006. The planning analysis presented in the
Planning Assessment (and summarised below) was prepared on the basis that Change 6 to the RRMP
would be notified before the RWSS resource consent applications are lodged and that the rules in
Change 6, being rules related to water27, have immediate ‘legal effect’.28
One aspect of the RWSS is located in the Coastal Marine Area whereby the Hawke’s Bay Regional
Coastal Environment Plan (Version 3) is relevant.
9.3.1 RMA Status of Activities within the Hawke’s Bay Region
There are permitted activity rules in the RRMP relating to the type of activities which form part of
the RWSS. However, due to the nature and scale of the proposed activities, the permitted activity
performance standards are exceeded in most instances, typically resulting in discretionary activity
status.
27 In terms of section 86B(3) of the RMA. 28 Change 6 was publicly notified on 4 May 2013, i.e. prior to the RWSS applications and notice of requirement being
lodged with the EPA.
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As noted above, Change 6 also needs to be considered as it relates to the management of land uses,
takes, and discharges within the Tukituki Catchment. In terms of the relevant rules, the key element
of Change 6 is the need, and ability, to lodge a global land use consent application for the use of
production land which will establish a set of limits and other measures in relation to the
management of nutrient discharges.
The scope and effect of Change 6 is discussed in more detail below.
The status of the proposed activities under the RRMP is summarised in Table 9.6.1 below.
Table 9.3.1a: RMA Activity Status of Activities under the RRMP
Activity Relevant Regional Plan Rule(s)
Activity Status
• Vegetation clearance and soil disturbance associated with earthworks to construct the headraces and pipe network.
Rule 7 Permitted
• Vegetation clearance and soil disturbance associated with earthworks to construct the dam, intake structures, and outfall structure where:
Vegetation clearance is within 5m of a permanently flowing river, or any other river with a bed width in excess of 2m.
Rule 8 Restricted Discretionary
• Discharge of contaminants into air from the operation of a moveable aggregate crushing and screening plant29 where there is no visible discharge of water spray or dust beyond the boundary of the subject property, or in the case of public land, beyond 50 metres from the discharge or beyond the boundary of the public land, whichever is the lesser.
Rule 25 Permitted
• Discharges to air that do not comply with other rules (i.e. discharges to air associated with all construction activities including concrete batching).
Rule 30 Restricted Discretionary
• Diversion and discharge of stormwater (including in relation to the area in which the proposed transformer will be located).
Rule 43 Controlled
• Discharge of contaminants onto or into land, or into water, or water into water, associated with the construction, operation, and maintenance of the Makaroro Dam on the Makaroro River, the water
Rule 52 Discretionary
29 Associated with concrete production for dam construction.
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intakes on the Waipawa River, the water distribution system, the water outfall structure, and including flushing flows released from the Makaroro Dam.
• Take and use of surface water associated the two water takes from the Waipawa River as well as any incidental water takes associated with construction activities for the irrigation scheme.
Rule 55 Discretionary
• Diversion of water not regulated under other rules. Rule 59 Discretionary
• The erection or placement of a dam or other barrier structure in, on, under or over the bed of a river, and:
Any associated damming and diversion of water;
Any associated discharge of sediment; and
Any associated disturbance of the river bed; where:
- The catchment area of the new structure exceeds 50ha;
- The volume of water to be stored or retained exceeds 20,000m³;
- The height of the structure (as measured vertically from the downstream bed to the crest) is greater than 4m; and
- Existing fish passage is not maintained.
Rule 69 Discretionary
• Bridges, culverts and other structures, including access structures (temporary and permanent) where the catchment size is greater than 150 ha, or the structure occupies an area exceeding 10 m2.
Rule 69 Discretionary
• The erection of structures (and the introduction of plants and trees) in, on, or under the bed of a river (or within 6m of a river) and within a land drainage or flood control scheme area.30 This will include the water intake structures, headraces, siphons, culverts, outfall structures and plantings.
Rule 71 Discretionary
• The extraction of sand, gravel or other material from the bed of a river (beyond the limits in Rule 73).
Rule 74 Restricted Discretionary
30 Parts of the RWSS, including structures, are located within the Upper Tukituki Flood Control Scheme (UTTFCS) area. See Appendix D for a map showing the extent of the UTTFCS.
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• Land use consent for the use of production land pursuant to section 9(2) of the RMA within the Tukituki River catchment.
Rule TT2
(Change 6)
Discretionary
• Maintenance of lawfully established structures, and associated disturbance, discharges of sediment and diversions.
Rule 64 Permitted
• Use of a lawfully established structure. Rule 63 Permitted
• Removal and demolition of structures (e.g. those associated with construction – coffer dams, diversion channels etc), and associated disturbance, diversion and discharge of sediment.
Rule 66 Permitted
As a mitigation measure for the reduction in the amount of sediment being transported downstream
due to the construction of the proposed Makaroro Dam, it is proposed that up to 3,400 m3 of
sediment be deposited on the beaches (within the Coastal Marine Area) to the north and south of
the mouth of the Tukituki River for beach nourishment purposes.
The status of the proposed beach nourishment under the Regional Coastal Environment Plan is
summarised in Table 9.3.1b below.
Table 9.3.1b: RMA Activity Status of Activities under the Regional Coastal Environment Plan
Activity Relevant Regional Coastal Environment Plan Rule(s)
Activity Status
• Beach nourishment (i.e. the deposition of sediment within the Coastal Marine Area).
Rule 139 Restricted Discretionary
Summary of Consent Requirements:
• Discretionary activity resource consent is required for:
the construction, operation, and maintenance of the dam, water intake structures, siphons, pipelines, and discharge structures within the rivers (and headraces within 6m of the rivers), including the associated culverts, damming and diversion of water, discharge of water and sediment, and disturbance of the river and stream beds;
the damming, diversion and discharge of water and the discharge of water and contaminants to
land and water;
the take and use of water for irrigation, electricity generation, construction, stock and domestic supply and other purposes;
the use of production land pursuant to section 9(2) of the RMA within the Tukituki River
catchment; and plantings within a Flood Control Area.
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• Restricted discretionary resource consent is required for:
any soil disturbance (earthworks) or vegetation clearance within 5m of a river;
discharges to air associated with construction activities;
the extraction of sand, gravel or other material from the beds of rivers; and
beach nourishment.
• Controlled activity resource consent is required for:
The diversion and discharge of stormwater. • All other aspects of the RWSS are either permitted activities under the rules of the RRMP or, as
discussed below, will be the subject of resource consent applications at a later date.
If the bundling approach is applied to the activities within the HBRC’s jurisdiction, the overall status
of the resource consent applications would be discretionary.
9.4 Department of Conservation
An Area of Significant Nature Conservation Value (Site 18) is located alongside the Makaroro River
within the reservoir that will be formed by the construction of the Makaroro Dam. Site 18 is
identified in Appendix D of the CHBDP as the “Bush margin – Makaroro River”, owned by the Crown
(in this case administered by the Department of Conservation).
On the basis of the above, an application will be made to the Department of Conservation for a
concession to inundate Site 18 after the resource consent applications are lodged for the RWSS.
9.5 Consenting Approach
The following presents the proposed approach in terms of the manner in which approval under the
RMA is to be sought for the RWSS (being a combination of a notice of requirement and resource
consent applications) as follows:
• A notice of requirement is being lodged with the EPA (for activities within the administrative
jurisdiction of the CHBDC) for the proposed primary headrace canal and pipelines located
within Zones A - D
• Resource consent applications are being lodged with the EPA for all other aspects of the
RWSS (for activities within the administrative jurisdiction of the CHBDC, HDC, and HBRC) that
are not permitted activities or otherwise proposed to be the subject of resource consent
applications at a later date (as discussed below).
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The aspects of the RWSS that are permitted activities and will not be the subject of any notice of
requirement or a resource consent application are set out in Table 9.5.1 below.
Table 9.5.1: Permitted Activities
Permitted Activities
The secondary pipelines.
The 33kV electricity lines.
Bridges associated with the primary distribution system headrace canal within Zones A - D.
In relation to the last item in Table 9.5.1 above, the Project Description (Tonkin & Taylor, May 2013a)
includes details in relation to bridges that will be constructed over the primary headrace canal. No
consents are required for these bridges on the basis of the following:
• To the extent they are proposed within ‘road reserves’ and form part of the road (i.e.
Caldwell Road, Ngaruru Road, and Wakarara Road), such activities fall within the ambit of
the existing designations relating to the roads in question within the Central Hawke’s Bay
District and could be undertaken by HBRIC Ltd under that designation (with the permission
of CHBDC – refer to sections 176 and 177 of the RMA)
• To the extent they are farm bridges (9 have been anticipated in the Project Description), they
will form part of the activities authorised by the designation for the primary headrace canals
• None of the proposed bridges relate to natural waterbodies (and the bridges will be
constructed prior to the conveyance of any water within the primary headrace canal) and
therefore do not give rise to the need for a resource consent within the administrative
jurisdiction of the HBRC.
The resource consent applications and the notice of requirement are being lodged with the EPA in
accordance with s.145 of the RMA.
9.5.1 District Council Jurisdiction
Comprehensive land use consent applications are being lodged with the EPA for the activities
associated with the RWSS within the administrative jurisdiction of each of the CHBDC and HDC.
9.5.2 Regional Council Jurisdiction
Applications for a total of 15 resource consents are being lodged with the EPA for the activities
associated with the RWSS within the administrative jurisdiction of the HBRC. The applications will be
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structured in a manner whereby there will be a single comprehensive resource consent application
for the construction, operation (on-going existence and running) and maintenance of each key
element of the RWSS (or group of similar activities) (e.g. dam, intake structures, siphons).
Each of the resource consent applications for the various structures is followed by a separate
resource consent application (where required) for the water related use of the structure (e.g.
damming, diversion, take, use and discharge of water) associated with each of the various elements
of the RWSS as required (post construction).
There are two land use consent applications, one for the use of production land, and the other for
plantings within a Flood Control Scheme area. Finally, there is an application for the deposition of
sediment within the Coastal Marine area to the north and south of the mouth of the Tukituki River
for the purposes of beach nourishment.
Each of the applications, along with an explanation as to what they cover (in ‘plain English’ terms), is
set out as follows. For consenting purposes, the scope of each application is a framed in Part A –
Resource Consent Applications.
Makaroro Dam
An application to build, operate, and maintain a dam on the Makaroro River (LU120370C)
This application includes everything to do with the construction of the Makaroro Dam such as
earthworks (including borrow areas and cut-to-waste disposal areas), vegetation clearance,
streambed works and gravel extraction, water takes, temporary coffer dams, construction lay down
areas, concrete batching, project offices and construction staff facilities, and all associated
discharges to land, air and water (including discharges of stormwater). Post-construction, it is
intended to cover all aspects of the on-going existence, operation and maintenance of the Makaroro
Dam itself. It does not cover the management and use of water stored within the reservoir behind
the dam which is covered by a separate consent – see below).
An application to operate the dam and reservoir (WP120371M)
This application covers the operation of the dam as it relates to the water in the reservoir following
construction. It authorises the filling of the reservoir behind the dam, storage of water in the
reservoir, diverting/taking water from the reservoir, using it for electricity generation or directing it
over the spillways, and then discharging it below the dam. The application includes a reference to
‘water-borne sediment’ on the basis that there will be sediment within the water column that will
pass through the dam. Minimum flows and flushing flows will be managed under this consent.
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Other Structures
Two applications are made to build and maintain the Upstream Water Intake Structure and the
Downstream Water Intake Structure on the Waipawa River (LU120372C and LU120374C)
An application is made to install and maintain siphons and/or pipelines associated with a water
distribution system under the beds of rivers and streams (LU120376C)
An application is made to build and maintain the headraces within, or near to, of the beds of rivers
and streams, and to also allow for emergency overflow / spillway discharges to land and surface
water (LU120377C)
Two applications are made to build and maintain two water outfall structures, one on a tributary
to the Mangaonuku Stream, and one on the Kahahakuri Stream (LU120378C and LU120380C)
These applications cover everything to do with the construction of these structures such as
earthworks (including borrow areas and cut-to-waste disposal areas), vegetation clearance,
streambed works and gravel extraction, water takes, construction lay down areas, concrete batching,
and all associated discharges to land, air and water (including discharges of stormwater).
Post-construction, these consents are intended to cover all aspects of the on-going existence,
operation, maintenance, and upgrading of the various structures themselves. They do not cover the
management and use of water through the structures - being the subject of separate consents).
Water Permits
Two applications are made to take water from the Waipawa River (via the two water intake
structures referred to above) and to use that water for water supply, including irrigation purposes
on production land (WP120373T and WP120375T)
These applications refer to providing a ‘water supply’ which is primarily for irrigation purposes, but
can also include other domestic and agricultural or horticultural purposes such as potable water (if
treated appropriately), stock water, frost protection, or dairy shed wash down. Any consents
granted pursuant to these applications will include upper limits as to the amount of water that can
be taken from the Waipawa River at each location. Where, how much, and for what purpose water
is used within the production land areas will be a function of the individual choices of land owners
obtaining water from the RWSS. These applications are framed in terms that permit the use of water
both within the five defined irrigation zones (A-D and M) and elsewhere by holders of existing
irrigation take consents in the Tukituki catchment.
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Discharge Permits
Two applications are made to discharge water and any associated contaminants through the
outfall structures referred to above to a tributary to the Mangaonuku Stream and the Kahahakuri
Stream (DP120379W and DP120381W)
The applications are intended to cover the discharge of water from the primary headrace canal and
pipeline network back into natural waterways which will then flow downstream to be collected by
the Downstream Water Intake Structure for use within Zone M, or remain in the river.
No discharge permit is required for the flow of residual water at the northern end of Zone M. At this
point any water is within the Papanui Stream which naturally flows into the Tukituki River.
Land Use Consent - Use of Production Land
A land use consent application for the use of production land within the Tukituki River catchment
facilitated by the RWSS (LU120382L)
This application complies with Change 6 relating to the Tukituki River catchment. It will allow for the
use and intensification of agricultural land within defined areas irrigated by the RWSS (i.e. Zones A –
D and M).
Any water supplied to properties beyond Zones A – D and M is intended to replace and/or
supplement existing ground or surface water takes which may be affected by the new minimum flow
requirements in Change 6 (discussed below). On the basis that this does not involve an increase in
the amount of water able to be used on those properties, no intensification of land use is facilitated
by the RWSS (compared with the existing situation) whereby the relevant land use rule in Change 6 is
not triggered. If (for any unforeseen reason) that is not the case, the individual farmer will be
responsible for obtaining any necessary resource consent. Likewise, if any resource consents are
required to enable exiting irrigators outside Zones A to D and M to access water released from the
Scheme for their use, obtaining such consents will be the responsibility of the irrigator.
Land Use Consent - Plantings in a Flood Control Scheme Area
An application to allow for trees and shrubs to be planted within the Upper Tukituki Flood Control
Scheme area (LU120388P)
This application is to allow plantings as proposed in the report: ‘Proposed Integrated Mitigation and
Offset Approach’ HBRIC (May 2013f).
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Beach Nourishment
An application to allow for the placement of sand and gravel for the purposes of beach
nourishment (LU120400D)
The construction of the Makaroro Dam will trap sand and gravel that would otherwise flow down the
river and out to the coast via the Tukituki River. This may have some effect on the beaches to the
north and south of the mouth of the Tukituki River. Accordingly, to address this situation, it is
proposed to deposit up to 1,700m3 of sand and gravel per year on each of the beaches to the north
and south of the mouth of the Tukituki River (a total of 3,400m3 of sand and gravel).
9.6 Term of Consents and Lapse Periods
As is normal practice with most land use consents within the jurisdiction of a territorial authority, no
term of consent is proposed (i.e. if the consent is given effect to, and the activity is not discontinued
for a period of 12 months or more, the consent will endure indefinitely). Accordingly, no term of
consent is sought in relation to the land use consents for the RWS Scheme for activities within the
administrative jurisdiction of the CHBDC and HDC.
Given the nature of the proposal and the scale of investment associated with the RWS Scheme, a
term of 35 years is sought in relation to all of the resource consents for activities within the
administrative jurisdiction of the HBRC. None of the applications for activities within the
administrative jurisdiction of the HBRC involve reclamations.
A lapse period of 10 years is sought in relation to all of the applications for activities within the
administrative jurisdiction of the CHBDC, HDC, and HBRC.
A lapse period of 10 years is also sought in relation to the designation for the primary headrace canal
and pipelines within the administrative jurisdiction of the CHBDC.
The 10 year lapse period is sought on the basis that:
• The Preliminary Construction Programme in Appendix B of the Project Description indicates
a construction period of approximately four and half years;
• There will be a lead-in period prior to construction associated with completing land owner
negotiations and agreements, contract management, financing, detailed design, and the
finalisation of the various management plans required by the proposed consent conditions
(see Part D); and
• An allowance for delays at any stage of the construction phase.
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It is also noted that, for similar reasons, a 10 year lapse period (or longer) is typically applied to other
large scale infrastructure development projects including New Zealand Transport Agency’s state
highway projects (e.g. sections of the Waikato Expressway)31 and renewable electricity generation
projects (e.g. Contact Energy Ltd’s Tauhara II Geothermal Development Project and the Hauāuru mā
raki - Waikato Wind Farm).
9.7 Applications to be made at a Later Date
There are a number of aspects of the RWSS that will or may be the subject of further resource
consent applications at a later date. Aspects of the RWSS in this category are mostly minor matters
or elements about which the location or details are unable to be determined prior to detailed design
and/or the construction phase. These activities are listed in Table 9.7.1 below along with the
reasons why no application is being made at this stage of the Scheme.
There are not considered to be any significant issues associated with applying for these additional
consents at a later date as they would not raise new issue or effects of a different kind or scale to
those associated with the activities for which consent is currently being sought. As such, it is not
necessary to enable a proper understanding of the effects of the RWSS to make those applications
now.
Table 9.7.1: Activities that Will or May be the Subject of Resource Consent Applications at a Later Date
Activity Jurisdiction Reason for Any Application being at a Later Date
Subdivision consents. CHBDC and HDC
There will need to be changes to the pattern of land tenure associated with the construction and operation of the RWSS, particularly in the vicinity of the proposed Makaroro Dam and the associated reservoir. The negotiations with land owners and land purchase arrangement will not be completed until after any consents have been granted for the RWSS, at which time the extent to which proposed changes to property boundaries and land ownership will be known and able to be formalised following any subdivision consents being obtained. Similarly any legal issues or property rights associated with the manner in which the land for the RWSS is held or controlled by HBRIC Ltd will be addressed at that time.
Sediment extraction from within the reservoir behind the
HBRC The application for the construction and operation of the Makaroro Dam includes the extraction of gravel
31 In the recent Board of Inquiry decision in relation to the MacKays to Peka Peka Expressway, a lapse period of 15 years was adopted.
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proposed Makaroro Dam (post construction) for the purpose of maintaining water storage capacity.
during construction, and on an ongoing basis to maintain the operational integrity of the water intake structure for the dam within the reservoir.
There could also be some extraction of gravel from the reservoir post construction for the purpose of maintaining water storage capacity of the reservoir. However, any such activity is not anticipated to be required for at least 20 years and the level of extraction required to maintain storage capacity is consistent with existing rates of extraction activity within the Makaroro / Waipawa / Tukituki Rivers, and as such would not introduce any new effects. Details of any such proposal would be determined at the time, including the method of extraction and the location(s) in which the sediment will deposited or used.
Stream crossings associated with secondary pipelines.
HBRC Underground pipelines for the distribution of water are permitted activities except where they cross the bed of a river or stream. The location of the secondary pipelines will not be known until after any consents for the RWSS have been granted and supply agreements are in place. At that time the location of the secondary pipelines and any associated stream crossings will be able to be determined and consents applied for at that time.
By-wash from secondary pipelines.
HBRC There will be a need to allow for by-wash (i.e. the discharge of any surplus water) within the secondary pipelines. The location of the secondary pipelines will not be known until after any resource consents for the RWSS have been granted and supply agreements are in place. At that time the location of the secondary pipelines and any associated points of discharge of by-wash will be able to be determined, and consents applied for accordingly. Such water is likely to be of relatively high quality and therefore discharge of low volumes to ground or to natural waterways is not likely to be an issue.
Bridges or other forms of stream crossings within Zone M.
HBRC Details in relation to the need for bridges or other forms of stream crossings associated with the use of the old Waipawa River bed and the Papanui Stream for the conveyance of water will be determined at a later date as part of arrangements to be entered into with landowners.
Sediment extraction for beach nourishment purposes.
HBRC An application will be made for the deposition of up to 3,400m3 per annum on the beaches to the north and south of the mouth of the Tukituki River for the purposes of beach nourishment. However, no application is being made at this stage for the extraction of river bed sediment to provide the 3,400m3 of material required. This is because HBRC operates a system whereby consents to extract
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sediment from the rivers in the Hawke’s Bay Region are applied for and granted on an annual basis. There is no point in applying for a resource consent as part of the current applications as it will expire before it is intended to be implemented (i.e. following the construction of the Makaroro Dam – some years away). In any event, if necessary, HBRIC is able to purchase material from one of the other holders of a resource consent to extract river bed sediment at the time the material is required.
9.8 Other Matters to be addressed at a Later Date
In addition to the need for additional resource consents that will be applied for at a later date
(discussed above), there are a number of other matters and/or legal processes than will, or may,
need to be addressed at a later date including:
• An application to the New Zealand Historic Places Trust for a general authority under section
12 of the Historic Places Act 1993 to be able to modify any archaeological site(s) that may be
discovered during construction activities;
• An application to the Director-General of Conservation under the Freshwater Fisheries
Regulations 1983 for the construction of the Makaroro Dam in relation fish passage and/or
fish transfer
• An application to the Department of Conservation for a permit under the Wildlife Act 1953
to translocate and/or potentially harm wildlife (e.g. bats and lizards) associated construction
activities
• Seeking approval from CHBDC under section 177 of the RMA to establish bridges and install
pipelines within road reserves that are the subject of an existing designation (including
consideration of any relevant legal requirements under the Local Government Act 1974
and/or codes of practice)
• The possible need for any road closures or licences to occupy in relation to any paper roads
• Any Development Contributions that may be payable to CHBDC or HDC.
These matters are not addressed any further in this AEE.
9.9 Policy Context
The Planning Assessment provides a planning analysis of the RWSS in relation to the relevant policy
and planning documents prepared under the RMA (sometimes referred to as ‘statutory instruments’)
that need to be considered as part of the assessment of the resource consent applications and the
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NOR. The planning analysis is presented in relation to the RWSS as an integrated Scheme (rather
than a separate analysis in relation to the applications and NOR).
The RWSS has been assessed in relation to the relevant aspects of the following statutory
instruments:
National Policy Statements
• National Policy Statement for Freshwater Management (NPSFM)
• National Policy Statement for Renewable Electricity Generation (NPS REG)
• New Zealand Coastal Policy Statement (NZCPS)
National Environmental Standards / Regulations
• Resource Management (National Environmental Standard for Sources of Human Drinking
Water) Regulations 2007
• Resource Management (National Environmental Standard for Assessing and Managing
Contaminants in Soil to Protect Human Health) Regulations 2011
• Resource Management (Measurement and Reporting of Water Takes) Regulations 2010
Regional Policy and Planning Documents
• Hawke’s Bay Regional Resource Management Plan (RRMP) including:
Proposed Change 4 – Managing the Built Environment (PC4)
Proposed Change 5 – Land Use and Freshwater Management (Change 5)
Proposed Change 6 – Tukituki Catchment (Change 6)
• Hawke’s Bay Regional Coastal Environment Plan (Coastal Plan)
District Plans
• Central Hawke’s Bay District Plan (CHBDP)
• Hastings District Plan (HDP)
In addition to the above, the RWSS has also been assessed in relation to the Proposed National Policy
Statement on Indigenous Biodiversity (Proposed NPSIB) and to a number of other non-statutory
resource management documents (discussed in the Planning Assessment).
The following provides a brief summary and the key conclusions presented in the Planning
Assessment in relation to the statutory instruments listed above.
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9.9.1 National Policy Statements
The NPSFM is the most relevant NPS to the RWSS. The major thrust of the NPSFM is the setting of
limits on both water quality and quantity that reflect national and local values. The way in which the
NPSFM is to be implemented is through the provisions of regional plans. Change 6 (discussed below)
sets out the planning provisions intended to implement the NPSFM in the Tukituki catchment within
which the RWSS is proposed.
The NPS REG recognises the national significance of renewable electricity generation activities. The
proposed generation of hydro-electricity as part of the RWSS is entirely consistent with the
outcomes sought to be achieved by the NPS REG.
The Proposed NPSIB is intended to provide clearer direction to local authorities on their
responsibilities for managing indigenous biodiversity under the RMA. It seeks to promote the
maintenance of indigenous biodiversity while recognising the rights and responsibilities of
landowners and the interests of Maori.
As the proposed NPSIB has not yet been finalised and gazetted it has no legal effect other than as a
potentially relevant matter under s.104(1)(c) of the RMA. However, HBRIC Ltd has anticipated the
likely effect of the proposed NPSIB, particularly in relation to indigenous biodiversity associated with
the Makaroro River and its environs where the Makaroro Dam and reservoir are proposed.
Specifically, the report ‘Proposed Integrated Mitigation and Offset Approach’(HBRIC, May 2013f))
sets out the way in which the residual biophysical effects (e.g. effects on terrestrial and aquatic
ecology) are addressed around the dam/reservoir area and downstream to the intake site, that are
not practicably able to otherwise be avoided, remedied, or mitigated directly or entirely.
The proposed beach nourishment is consistent with the relevant objectives and policies in the
NZCPS, which include promoting the restoration or rehabilitation of the natural character of the
coastal environment and which can include restoring and protecting riparian and intertidal margins.
9.9.2 National Environmental Standards / Regulations
The RWSS will be consistent with all relevant National Environmental Standards / Regulations. None
of the resource consent applications associated with the RWSS are triggered by the relevant National
Environmental Standards / Regulations.
The Resource Management (Measurement and Reporting of Water Takes) Regulations 2010 have
been complied with as part of the proposed conditions (Part D – Proposed Conditions).
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9.9.3 Regional Policy and Planning Documents
The RRMP is a combined regional policy statement (RPS) and a regional plan. It sets out a wide range
of objectives, policies and methods (mainly rules) in relation to the management of natural and
physical resources within the jurisdiction of the HBRC.
Change 5 proposes to introduce new provisions relating to the integrated management of water and
land into the RPS parts of the RRMP. The provisions of Change 5 are of particular relevance to the
RWSS as they set out the overarching approach to the integrated management of water and land
resources with a focus on a catchment based approach including specifically in relation to the
Tukituki River catchment. Water storage and the use of that water for maintaining or enhancing
land-based primary production are explicitly recognised and provided for as part of the relevant
objectives and policies in Change 5.
Given the nature of the proposed activities comprising the RWSS, Change 6 is the key planning
document which is central to the assessment and determination of the resource consent
applications within the administrative jurisdiction of the HBRC. Change 6 inserts new sections in
Chapters 5 (5.9) and 6 (6.9) of the RRMP relating to the Tukituki River catchment within which the
RWS Scheme is proposed to be located. It is the first of a number of catchment specific plan changes
for the Hawke’s Bay Region which seek to implement the NPSFM, as well as address specific water
allocation and water quality issues in the catchment.
The objectives in Change 6 put in place a strong policy regime seeking to sustainably manage the
fresh water resources within the Tukituki River catchment in accordance with the NPSFM. One of
the objectives in Change 6 is to enable Community Irrigation Schemes such as the proposed RWSS,
subject to the outcomes in other objectives being achieved.
Change 6 sets out 15 policies which specify the manner in which the objectives for the Tukituki River
catchment are to be achieved. Of relevance to the RWSS, this includes the setting of limits and
targets in relation to nitrate-nitrogen, dissolved reactive phosphorus, periphyton biomass, and
Escherichia coli. The policies also identify environmental state indicators32 for the Macroinvertebrate
Community Index (MCI), Visual Water Clarity and Deposited Sediment.
32 “Indicators” define what the state of certain water quality parameters should be in order to safeguard the life supporting
capacity of the water body but they are not “limits” or “targets”. The “indicators” stated will be used by Hawke’s Bay Regional Council to monitor the effectiveness of the RRMP in achieving the purpose of the RMA in the Tukituki River catchment.
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Of particular relevance to the RWSS, one of the policies in Change 6 is to enable takes of water for
Community Irrigation Schemes capable of providing irrigation water to at least 5,000 hectares of
production land provided that the management of the take and the management of the Scheme
addresses a range of specified matters. Change 6 also includes a policy which sets out the criteria for
considering an application for the use of production land on multiple properties associated with the
operation of a Community Irrigation Scheme.
The manner in which the RWSS addresses the requirements set out in the objectives and policies in
Change 6 is the subject matter of a number of technical reports appended to this AEE and
summarised in later sections of this document. In this regard, the key aspects of the RWSS which are
intended to address the objectives and policies in Change 6 are as follows:
• A proposed flow management regime (described in the Project Description Tonkin & Taylor,
May 2013a and in the Environmental Flow Optimisation Report Aquanet, May 2013) which
includes a minimum flow out of the Makaroro Dam and flushing flows which will result in a
more consistent flow of water in the rivers downstream of the dam and an improvement in
the water quality (including reducing the incidence of periphyton biomass)
• Monitoring and management of water quality in the reservoir
• The management of uses of land authorised by the consents in a manner that:
o Does not cause specified in-river nitrate-nitrogen concentration limits to be exceeded at
any of the specified monitoring locations
o Does not cause a net increase of Dissolved Reactive Phosphorus (DRP) reaching
waterways compared to the existing discharges of DRP to surface waters as at 6 May
2013 modelled as the Current Land Use Scenario in the NIWA Stream Modelling Report
(TRIM 2 Scenario Modelling) (NIWA, May 2013b)
o Does not cause the water quality limits for E. coli in surface and groundwater specified in
Change 6 to be exceeded
• The preparation of:
o A Groundwater Monitoring Plan (GMP)
o An Irrigation Environmental Management Plan (IEMP)
o A Farm Environmental Management Plans (FEMPs)
o An On-Farm Monitoring Plan
• Farm Environmental Management Plan Audits
• Contractual arrangements between the consent holder and recipients of water from the
RWSS.
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The key outcomes to be achieved in accordance with the objectives and policies in Change 6 are also
the subject of proposed consent conditions (see Part D – Proposed Conditions).
The Coastal Plan is relevant to the proposed beach nourishment to the north and south of the mouth
of the Tukituki River. The proposed beach nourishment will be undertaken in a manner which is
consistent with the relevant guideline the Coastal Plan relating to the deposition of material within
the Coastal Marine Area.
9.9.4 District Plans
The RWSS will be located within the Rural Zones in the CHBDP and the HDP.
The CHBDP and the HDP both provide for the development and operation of utilities / network
utilities. The inclusion of hydro-electricity generation as part of the proposal means that the
Makaroro Dam and the associated reservoir (to the extent the latter is within the Central Hawke’s
Bay District) fall outside of the definition of ‘utility’ in the CHBDP. However, most of the other
aspects of the RWSS are utilities for the purposes of the CHBDP. The part of the reservoir in the
Hastings District is a type of ‘network utility’ in the HDP.
The RWSS has been developed and advanced in a manner which is consistent with the objectives and
policies in the CHBDP and the HDP relating to utilities / network utilities and the Rural Zones in which
the RWSS is proposed to be located.
The storage and use of hazardous substances is an aspect of the RWSS that gives rise to the need for
a resource consent within the administrative jurisdiction of CHBDC. The management of hazardous
substances is addressed in the Draft Construction Environmental Management Plan (CEMP) (see
Schedule Six of Part D – Proposed Conditions) in a manner which is consistent with the objectives and
policies in the CHBDP. Similarly, the management of earthworks and other environmental effects
associated with construction activities are addressed in the CEMP. The proposed conditions of
consent (Part D – Proposed Conditions) require that the consent holder complies with the CEMP at
all times.
Finally, the farming activities, including land use change and/or intensification, facilitated by the
RWSS (undertaken by third parties) are provided for as permitted activities in the CHBDP and the
HDP, in which case it can be inferred that those activities are consistent with the relevant objectives
and policies in the district plans.
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9.10 Statutory Assessment of Notice of Requirement
Section 171 of the RMA specifies the matters that a territorial authority must have particular regard
to when considering a NOR, as follows:
171 Recommendation by Territorial Authority
(1A) When considering a requirement and any submissions received, a territorial authority
must not have regard to trade competition or the effects of trade competition.
(1) When considering a requirement and any submissions received, a territorial authority
must, subject to Part 2 consider the effects on the environment of allowing the
requirement, having particular regard to—
(a) any relevant provisions of—
(i) a national policy statement:
(ii) a New Zealand coastal policy statement:
(iii) a regional policy statement or proposed regional policy statement:
(iv) a plan or proposed plan; and
(b) whether adequate consideration has been given to alternative sites, routes,
or methods of undertaking the work if—
(i) the requiring authority does not have an interest in the land
sufficient for undertaking the work; or
(ii) it is likely that the work will have a significant adverse effect on the
environment; and
(c) whether the work and designation are reasonably necessary for achieving
the objectives of the requiring authority for which the designation is sought;
and
(d) any other matter the territorial authority considers reasonably necessary in
order to make a recommendation on the requirement.
In terms of section 171(1), this document presents a comprehensive Assessment of Environmental
Effects which forms part of the NOR for the RWSS.
The policy and planning documents listed in section 171(1) (a) are discussed in this section of the
document and in more detail in the Planning Assessment (EMS May, 2013b).
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The matters in section 171(1(b) are addressed the report Alternatives Assessment - Primary
Distribution System Zones A to D (Schedule Four of Part B). Key elements of that analysis have
already been noted in the context of the discussion of the Scheme Development Process (Section 2
above), but in summary, the report describes the methodology that was applied to assessing
alternative options for the primary distribution system of the water distribution network servicing
Zones A to D associated with the proposed Scheme.
Alternative sites, routes and methods of undertaking the work have been considered, taking into
account relevant Part 2 matters and the potential environmental effects associated with each
option. The Project Team engaged with potentially affected landowners and has incorporated
outcomes of the environmental, social and cultural studies, undertaken throughout the full feasibility
phase of the Scheme, into the assessment process.
Three primary conveyance options: a trapezoidal open canal, a plastic-lined rectangular aqueduct,
and a buried pressure pipeline were considered. 220m RL and 240m RL alignments were considered
for the open canal and aqueduct options and a third alignment was defined for the buried pressure
pipeline. A hybrid option incorporating a mixture of open canal and buried pipeline was also
developed and refined after landowner discussions. This refined hybrid option was ultimately
identified as the preferred option for designation based on evaluation of all relevant factors
including environmental, engineering and economic, and optimisation of the preferred alignment
has continued through further engagement with relevant landowners.
In terms of section 171(1)(c), it is considered that the preferred option for the water distribution
network servicing Zones A to D (and the designation for this work) is reasonably necessary for
achieving the objectives of the requiring authority for the following reasons:
• The proposed water distribution network is an essential element of the Scheme which will
enable the conveyance and distribution of water to participating landowners.
• The designation sought is the most appropriate method of securing the necessary land use
approval for the primary distribution system headrace canal and pipeline within Zones A to D
of the Scheme that extend over some 36 kilometres of land in private and public ownership
(and alongside those aspects of the Scheme that will be approved by way of resource
consents).
• Restrictions on land and water associated with (and occupied by) the primary distribution
system headrace canal and pipeline within Zones A to D of the Scheme are reasonably
necessary for the safe or efficient functioning or operation of the water distribution network.
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The consent authority (in this case the Board of Inquiry, assuming the Minister refers HBRIC Ltd’s
applications and NOR to a Board of Inquiry) will need to consider what, if any, additional matters are
relevant under section 171(1)(d) of the RMA.
9.11 Part 2 of the RMA
A detailed assessment of the RWSS has been undertaken in relation to Part 2 of the RMA in the
Planning Assessment. The conclusion of the Planning Assessment was expressed in the following
terms:
The purpose of the RMA as set out in section 5(1) of the RMA, which is:
To promote the sustainable management of natural and physical resources.
Section 5(2) of the RMA defines sustainable management as:
Managing the use, development and protection of natural and physical resources in a way or
at a rate which enables people and communities to provide for their social, economic, and
cultural wellbeing and for their health and safety while-
a) Sustaining the potential of natural and physical resources (excluding minerals) to
meet the reasonably foreseeable needs of future generations; and
b) Safeguarding the life-supporting capacity of air, water, soil and ecosystems; and
c) Avoiding, remedying or mitigating any adverse effects of activities on the
environment.
The promotion of sustainable management requires an overall broad judgement of whether a
proposal will meet the requirements of section 5(2) of the RMA. The approach recognises that the
RMA has a single purpose – sustainable management. Such a judgement allows for the comparison
of conflicting considerations and the scale or degree of them and their relative significance or
proportion in the final outcome.
The RWSS will enable people and communities to provide for their social, economic, and cultural
well-being and for their health and safety by the provision of water (primarily for irrigation) that will
facilitate an increase in the productive potential of their land, generating significant regional
economic benefits. It will also involve the generation of electricity from a renewable source and
create employment and associated economic activity.
The removal and/or inundation of areas of significant indigenous vegetation and significant habitats
of indigenous fauna is an adverse effect of the RWSS that is inconsistent with section 6(c) of the
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RMA. However, offset mitigation measures are proposed to address this effect. Other actual and/or
potential adverse effects on the environment will be avoided, remedied or mitigated by the
imposition of appropriate conditions of consent such that the Scheme is appropriate relative to
relevant matters of national importance.
The overall conclusion reached in the Planning Assessment is that the RWSS is consistent with the
purpose and principles of the RMA and would promote the overall sustainable management
purpose.
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10 INTRODUCTION TO MODELLING ASSESSMENTS
The RWSS involves alteration to a number of physical processes that in turn impact on the
environment. In order to form a basis for the assessment of environmental effects, HBRIC Ltd has
commissioned a number of modelling assessments in order that the nature and scale of the changes
the RWSS will have to the environment can be better understood.
The modelling assessments are collected together in the supporting reports as “M” reports. Each
report contains an executive summary. Rather than seek to paraphrase the reports, those executive
summaries are reproduced in the authors’ own words (subject to minor style, referencing and tense
changes where appropriate) in the following sections.
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11 GROUND / SURFACE WATER FLOWS – SCENARIO MODELLING
11.1 Scenarios Modelled
The study undertaken by HBRC Science Group (Ground and Surface Water Flows – Scenario
Modelling HBRC Science 2013a) investigated the potential impact of the RWSS on water resources in
the Tukituki Catchment and Ruataniwha Basin. A range of water resource management scenarios
were modelled incorporating different levels of water abstraction, with and without the operation of
the proposed RWSS. Further work has also been completed by Golder Associates (NZ) Ltd reported
in the Flow Optimisation Report (Aquanet, May 2013) to allow the economics of multiple water use
scenarios to be modelled.
As discussed in earlier sections, the Ruataniwha Plains are located in central Hawke’s Bay overlying
the Ruataniwha Basin and aquifer within the Tukituki River Catchment. The Ruataniwha Plains
contain a land area of approximately 40,000 hectares which has significant agricultural potential.
Approximately 6,000 hectares of the plains are currently irrigated, principally supplied by
groundwater abstracted (pumped) from the Ruataniwha Aquifer. Water is also abstracted from the
Tukituki River and its tributaries. The security of groundwater and surface water supply will be
reduced as new policy increases minimum flows in adjacent water bodies; consequently the
provision of irrigation from a water storage scheme is being investigated. Other studies have
identified that approximately 25,000 hectares of potentially irrigable land within the Tukituki
Catchment could be supplied with water from the RWSS.
Five water resource management scenarios were considered:
Scenario 1 Natural system (pre-irrigation abstraction conditions)
Scenario 2 Current ground and surface water abstraction continues up to the end of 2016
Scenario 3 RWSS operates from 2017 to 2022, with current ground and surface water
abstraction discontinued from 2017
Scenario 4 RWSS operates from 2017 with current ground and surface water abstraction
continuing to 2022
Scenario 5 RWSS operates from 2017 with current groundwater abstraction continuing to 2022,
while surface water abstraction is discontinued from 2017
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A transient numerical groundwater model developed by Hawke’s Bay Regional Council was used to
simulate changes to the aquifer system in terms of aquifer storage, aquifer-spring interactions and
aquifer-river interactions.
The change in groundwater contribution to river flows within the Ruataniwha Basin and the change
to river flow regimes were also simulated under each of the five scenarios at three river flow sites:
• Tukituki River at Tapairu Rd
• Waipawa River at RDS
• Tukituki River at Red Bridge
Scenarios incorporating the RWSS (Scenarios 3, 4 and 5) were compared to Scenario 2 (representing
the effect of ‘current abstraction’ on the resource) which was simulated to the end of 2016 prior to
the start of the RWSS in 2017. Scenario 2 was also compared to Scenario 1 which represents the
natural system.
11.2 Effects on the Aquifer System
The Scenario 3 simulation predicts a significant recovery in Ruataniwha aquifer storage by 2022 (36
million cubic meters ( MCM) relative to Scenario 2, with spring flow returning to near-natural levels
as a result of all abstraction within the basin ceasing.
No differences in predicted changes to the aquifer system under Scenarios 4 and 5 could be
detected. Scenarios 4 and 5 predict a decrease in the aquifer storage, spring flow and groundwater
contribution to river flow similar to those predicted under Scenario 2.
The aquifer system is predicted to be close to dynamic-equilibrium from 2017 to 2022 under
Scenarios 2, 4 and 5; accordingly minimal changes in aquifer storage would be expected after 2022.
The total aquifer storage loss predicted at the end of the simulation period for Scenarios 4 and 5 (31
December 2022) relative to natural conditions was 68 MCM.
The decrease in spring flow predicted under Scenarios 4 and 5 for 2010-2022 compared to the 1990-
1995 (near-natural conditions) is approximately 60 l/s, which is similar to the decrease in spring flow
predicted at the end of the simulation for Scenario 2.
The groundwater contribution to river flow in the Upper Tukituki and Waipawa Rivers (shown in the
following figures) is greatest when the system is at ‘natural’ conditions (Scenario 1).
Under Scenarios 2, 3, 4 and 5, groundwater contribution to river flow is predicted to decrease
relative to natural conditions up to the end of 2016. This decrease is attributed to continued
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abstraction from the aquifer. Under Scenario 2, groundwater contribution to river flow is predicted
to stabilise from the beginning of 2017.
Under Scenario 3, an increase in groundwater contribution to river flow is predicted from 2017 to
2022 in both the Waipawa and Tukituki Rivers. The groundwater contribution to river flow is
predicted to recover to near-natural conditions at the end of the simulation period in 2022 with only
minor further changes expected after that time.
Under Scenarios 4 and 5, a minor decrease in the groundwater contribution to the Waipawa River is
predicted from 2017 whereas groundwater contribution to the Tukituki River remains relatively
stable.
Aquifer/groundwater (GW) contribution to Tukituki River flow under Scenarios 1-5
Aquifer/groundwater (GW) contribution to Waipawa River flow under Scenarios 1-5
2600
2800
3000
3200
3400
3600
3800
4000
4200
4400
4600
4800
5000
5200
14/0
1/90
14/0
1/92
14/0
1/94
14/0
1/96
14/0
1/98
14/0
1/00
14/0
1/02
14/0
1/04
14/0
1/06
14/0
1/08
14/0
1/10
14/0
1/12
14/0
1/14
14/0
1/16
14/0
1/18
14/0
1/20
14/0
1/22
GW C
ontr
ibut
utio
n to
Riv
er F
low
(l/s
)
Tukituki Scenario 1 GW Contibution to River Flow 1990-2022 (l/s) Tukituki Scenario 3 GW Contibution to River Flow 1990-2022 (l/s)
Tukituki Scenario 4 GW Contibution to River Flow 1990-2022 (l/s) Tukituki Scenario 5 GW Contibution to River Flow 1990-2022 (l/s)
Tukituki Scenario 2 GW Contibution to River Flow 1990-2017 (l/s)
1400
1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500
2600
14/0
1/90
14/0
1/92
14/0
1/94
14/0
1/96
14/0
1/98
14/0
1/00
14/0
1/02
14/0
1/04
14/0
1/06
14/0
1/08
14/0
1/10
14/0
1/12
14/0
1/14
14/0
1/16
14/0
1/18
14/0
1/20
14/0
1/22
GW C
ontr
ibut
ion
to R
iver
Flo
w (l
/s)
Waipawa Scenario 1 GW Contibution to River Flow 1990-2022 (l/s) Waipawa Scenario 3 GW Contibution to River Flow 1990-2022 (l/s)
Waipawa Scenario 4 GW Contibution to River Flow 1990-2022 (l/s) Waipawa Scenario 5 GW Contibution to River Flow 1990-2022 (l/s)
Waipawa Scenario 2 GW Contibution to River Flow 1990-2017 (l/s)
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11.3 Effects on River Flows
The potential effects of operating the RWSS on river flows are summarised by scenario and flow
statistic in the table below. When interpreting the table below the following descriptions of the flow
statistics apply:
• Median is the flow that is equalled or exceeded 50% of the time over the period of record.
• Mean flow is the arithmetic average of all measured flows over the period of record.
• Q99 is the flow that is equalled or exceeded 99% of the time over the period of record. The
Q99 is used as a descriptor of the low flow of a river
• MALF (mean annual low flow) is the average of the lowest flow recorded/measured in each
year of the record. MALF is calculated as a 7-day moving average over the hydrological year
(July-June) excluding years with gaps in the record during which the annual minimum may
have occurred.
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* Days per year averaged over the modelled river flow record
The modelling predicts improvement in the Q99 low flow statistic across all modelled scenarios. The
modelling suggests the most significant change will occur in mid to high range flows across scenarios
3, 4 and 5 in the Waipawa and Tukituki rivers. The reduction in mid to high range flows reflects the
impact of the dam intercepting and storing Makaroro River flows, discharging a residual flow and
releasing flow for subsequent abstraction downstream for irrigation purposes. Minor increases in
mid to high range flows are predicted in the Upper Tukituki River due to not being directly affected
by the scheme.
In comparison to Scenario 2, a significant decrease in days where river flow is less than or equal to
the proposed minimum flow is predicted at all sites under Scenario 3. At each site, days less than or
equal to the proposed minimum flow are predicted to return near to that shown in the natural flow
regime under Scenario 1.
The RWSS as proposed will not involve abstraction or retention of water from the Tukituki River
upstream of the confluence with the Waipawa River. Modelling predicts that discontinuing
groundwater and surface water abstractions from 2017 and migrating them to the RWSS (Scenario
3), would have a positive impact on river flows in the Tukituki River at Tapairu Rd, predicting that
river flows would return to near-natural conditions (Scenario 1) by 2022.
Migrating all current groundwater and surface water abstractions to the RWSS under Scenario 3
predicts some significant gains for rivers at low flow conditions compared to Scenario 2 (under which
current abstraction continues).
The scenarios modelled in this report were designed to predict relative changes to a complex
dynamic system when changes are made to various input parameters. Some future predictive input
parameters were averaged from historical records. An additional margin of uncertainty was
introduced by strong reliance on literature values for input parameters where measured data was
not readily available.
In addition, modelling current levels of surface water abstraction (which includes stream depleting
groundwater abstraction) on river flow records used estimates of actual water use throughout a
typical year. These estimates were based on available metered water use (abstraction) data. The
available metered data for the Tukituki Catchment was limited to 2007-2008. In the absence of
additional metered data, it was assumed that 2007-2008 represented a typical year of surface water
abstraction in the Tukituki Catchment. Groundwater abstraction estimates used in the transient
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groundwater model were based on crop water demand studies and available metered well
abstraction data.
Irrigation return flow resulting from the RWSS irrigation was considered in this investigation, but was
not modelled specifically, consistent with an environmentally conservative approach. Recent work
conducted by the National Institute of Water and Atmospheric Research (NIWA) identified a 14% to
20% irrigation return flow is likely, excluding on-farm water losses (Leaching Losses on the
Ruataniwha Plain - NIWA Letter Report, 15 February 2013). At full uptake of available RWSS water,
this equated to between 10 and 15 MCM/year (greater if on-farm losses are included). This
corresponds to 3.9% to 5.8% of the estimated average annual recharge from rainfall in the
Ruataniwha Basin, which is not significant. When comparing low flow statistics under scenarios 3, 4
and 5, irrigation return flow may potentially have a more than a minor effect and may elevate low
flow statistics (significantly in some cases). It is recommended that this potentially positive effect of
irrigation return flow on low flow statistics should be further investigated.
In view of the previous statements, the model outputs in this study should be used principally for
comparing relative changes between scenarios rather than predicting absolute changes or making
comparisons with actual values.
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12 TUKITUKI RIVER NUTRIENT MODELLING
12.1 Introduction
Modelling of the changes to water quality of the Tukituki catchment is set out in three inter-related
reports:
• M2: OVERSEER® Nutrient Budgets Modelling (AgResearch, May 2013)
• M3: Stream Modelling (TRIM2 Calibration) (NIWA, May 2013a)
• M4: Stream Modelling (TRIM2 Scenario Modelling) (NIWA May, 2013b)
12.2 OVERSEER® Nutrient Budget’s Modelling
This study was undertaken by AgResearch assisted by contributing authors from HBRC (AgResearch,
May 2013).
The report contains a brief description of the OVERSEER® nutrient budgets (Overseer) which was
used to capture the effect of different land management practices on nutrient (N and P) discharges.
Overseer files were generated for historic, current, and future land uses. Historic land use was
modelled to investigate lag effects between land use practice occurring on the surface at a given
time, and the impact of the river occurring in the future. Current and future farms, also referred to
as pre-storage and post-storage, were based on economic farm feasibility studies. In addition, future
land uses with mitigation options were also modelled to determine whether mitigation options could
be used to achieve a future targeted reduction in nutrient loads. The assumptions and data used to
generate the Overseer files, and the nutrient discharges associated with each mapping unit are also
included in the report.
The output from this Overseer modelling has been used as an input to the NIWA nutrient modelling
for the Tukituki Catchment described below.
12.3 Stream Modelling (TRIM2 Calibration)
This study is the first of two inter-related NIWA reports - NIWA (May 2013a).
An earlier NIWA study (The NIWA TRIM1 Report produced for the 2012 Feasibility Study)
recommended further work to model additional scenarios including:
• Mitigating both N and P losses
• A wider range of modified land uses
• Changing the mix of land uses modelled, and
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• Extending the model to the entire Tukituki catchment.
Model extensions were required to assess the impact of irrigation and land use intensification within
the Ruataniwha Plain and the Papanui catchment, notably where groundwater upwelling occurs and
‘hot spots’ of N and P occur.
NIWA (May 2013a) extends the land use model TRIM2_CATCHMENT upstream from Waipukurau and
Waipawa, details model calibration and discusses model uncertainties. The TRIM2 model is
calibrated and tested and can now be used to predict the likely impacts of land use intensification
associated with the RWSS, including the effects of groundwater upwelling which results in ‘hot spots’
of high N and P concentration.
Modelling of future land use scenarios and their likely impact on stream nutrients and periphyton
biomass are reported separately in NIWA (May 2013b) as discussed below.
12.4 Stream Modelling (TRIM2 Scenario Modelling)
The second of the two NIWA Modelling reports is NIWA (May 2013b).
The report extends the stream nutrient and periphyton model TRIM1_STREAM to the whole of the
Tukituki catchment, details model calibration and discusses model uncertainties. The revised model,
TRIM2_STREAM, uses water and nutrient inflows predicted by the TRIM2_CATCHMENT model which
is described above (NIWA, May 2013a). The TRIM2 models are used to assess the likely impacts of
the RWSS on nutrient losses, stream nutrient inflows and concentrations, and stream periphyton
biomass.
The TRIM2_STREAM model satisfactorily predicts observed stream nitrogen and phosphorus
concentrations, and biomass for a representative pre-irrigation year, 2010. However, there are
several different combinations of key model coefficients that give a similar match between predicted
and observed stream nutrient concentrations and biomass. The strategy adopted to cope with this
non-uniqueness problem with model calibration is to identify the processes and model coefficients
that have the greatest effect on model predictions, seek alternative calibrations, and determine
whether model uncertainty affects the main conclusions and recommended actions. The
TRIM2_STREAM model is considered to be sufficiently reliable to assess the impact of the RWSS,
bearing in mind areas of uncertainty in its calibration.
The modelling confirms that phosphorus, rather than nitrogen, determines periphyton biomass,
except occasionally near the sea during summer low flows. In the middle Tukituki (from above
Waipukurau to near Red Bridge), dissolved inorganic nitrogen concentrations are well in excess of
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the concentrations that limit plant growth. It is only in the lower Tukituki (from near Red Bridge to
the sea) that, during prolonged periods of summer low flow, nitrogen concentrations are low (largely
as a result of denitrification) and nitrogen becomes limiting to plant growth.
Sensitivity analysis indicates that phosphorus supply, rather than phosphorus concentration,
determines periphyton biomass. Phosphorus supply is largely determined by phosphorus inflows
determined by OVERSEER and routed through the catchment by TRIM2_CATCHMENT. In NIWA,
2013a a satisfactory match was obtained between observed and predicted annual flow-weighted
mean phosphorus concentrations which indicates that phosphorus inflows to streams are predicted
satisfactorily.
This report predicts stream phosphorus concentrations and periphyton biomass assuming that the
WWTPs at Waipukurau and Waipawa discharge at their current levels. Consents for these
discharges, which come into force in 2014, require a reduction in phosphorus discharges. A
reduction in phosphorus discharges from the WWTPs will have beneficial effects for the lower
Tukituki River (from Waipukurau to the sea) in terms of reduced periphyton growth rates and
biomass.
The model predicts, and there are limited observations to support the prediction, that at times
biomass is high above the WWTPs as a result of runoff from agricultural land. In order to minimise
the adverse impact of the RWSS on periphyton biomass in the middle reaches of the Tukituki and
Waipawa Rivers (viz., above Waipukurau and Waipawa) it is desirable to minimise phosphorus inputs
resulting from the RWSS.
A key recommendation arising from the modelling is that phosphorus losses from the RWSS should
be minimised in order that nuisance periphyton growths should not occur more frequently, or be
more severe, than they are currently. In the lower Tukituki River the combination of phosphorus
input reductions from the WWTPs and the mitigation of phosphorus losses from agricultural land,
while not eliminating problems, is predicted to have benefits by reducing the incidence and severity
of nuisance periphyton growths.
One aspect of the Tukituki River that is not well understood is phosphorus exchange between the
stream bed and the overlying water, and it is desirable to undertake experimental work on this topic.
Since mitigation measures are proposed to ensure that RWSS is ‘phosphorus-neutral’ (viz.,
phosphorus inflows to streams do not increase as a result of the scheme) it is unlikely that the
phosphorus exchange with the bed will change significantly. Consequently, uncertainties in the
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modelling of phosphorus exchange are considered unlikely to invalidate the recommendation to
maintain or reduce phosphorus losses from the catchment.
Assuming current farming practice with no additional on-farm mitigation to reduce nutrient loss,
nitrogen and phosphorus losses across the entire catchment are predicted to increase by 32% and
6% respectively as a result of land use intensification associated with the RWSS. Nitrogen and
phosphorus losses within the irrigation consent area are predicted to increase by an average of 81%
and 41% respectively (Table 3 11 of the Report). These increases assume current farming practice
with no additional on-farm mitigation to reduce nutrient loss.
Fencing to exclude stock from streams and the optimal use of phosphorus fertiliser are predicted to
offset the 6% increase in phosphorus losses, and make the RWSS close to phosphorus-neutral
overall. Within the irrigation consent area, these measures are predicted to result in increase
phosphorus losses by 7% relative to pre-irrigation levels – significantly lower than the predicted 41%
predicted without any mitigation, but still not ‘phosphorus-neutral’. OVERSEER probably under-
estimates the benefits of stock exclusion from streams, because it only quantifies the consequences
of direct deposition of dung and urine, but not trampling of the banks and stream bed.
Nevertheless, additional mitigation measures may be required in some irrigated sub-catchments for
them to be ‘phosphorus-neutral’. There are a number of additional on-farm mitigation measures
that can be undertaken to reduce phosphorus losses (McDowell and Nash 2012).
Note that it will not be possible to completely eliminate nuisance periphyton growths during
prolonged summer low flows through phosphorus control alone. Currently, during prolonged
summer low flows, periphyton biomass reaches nuisance levels in most parts of the river, including
reaches apparently unaffected by nutrient runoff from agriculture. In such reaches, nutrient inflows
and growth rates are low, biomass accumulates slowly but, if there is a long period without ‘reset’
flows, often reaches nuisance levels.
In parts of the river where nutrient concentrations are high, periphyton growth rates are high.
Periphyton growth is offset by losses (respiration, death, grazing and scour) and biomass
accumulates at the net rate (growth minus losses). Consequently, biomass accumulates more
quickly, and nuisance levels are reached more quickly, where nutrient inflows are high. In addition,
peak biomass is usually higher than where nutrient inflows and concentrations are low.
If phosphorus mitigation is effective, then it is predicted that periphyton biomass in the main stem of
the Tukituki River will be similar to current levels. Nuisance biomass levels may still occur during
prolonged periods of low flow, but there should be no significant increase in the frequency or
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magnitude of nuisance growths. This conclusion is robust to uncertainty about phosphorus release
from the bed. Earlier modelling using TRIM1 (Rutherford et al. 2012) showed that when phosphorus
inflows from the WTTPs decrease, the frequency or magnitude of nuisance growths in the lower
Tukituki River are expected to decrease.
Periodically, natural high flows ‘reset’ biomass to low levels and it may be possible to alleviate
periphyton biomass problems by releasing flushing flows from the dam. The RWSS proposal now
includes the release of up to four flushing flows per irrigation season as discussed in Aquanet (May
2013). These additional flushing flows have not been incorporated in the TRIM modelling presented
in this report, but a preliminary quantitative assessment of the effects of these flushing flows on
periphyton biomass could be undertaken using TRIM_STREAM.
No monitoring data exist to compare with model predictions in most of the smaller streams –
predictions should therefore be treated with caution. Nevertheless, predictions highlight where
potential ‘hot spots’ of high nutrient, and potentially high biomass, are likely to occur. In some sub-
catchments, phosphorus inflows are predicted to be higher than pre-irrigation inflows. Additional
phosphorus mitigation measures may be required in such sub-catchments to avoid problems
associated with high biomass.
Nitrate concentrations are predicted to increase significantly in tributaries draining the irrigation
consent areas. Under current conditions, ‘hot spots’ of high nitrate concentration have been
identified in some tributaries of the middle Tukituki, which raises concerns about possible nitrate
toxicity. Assuming the same denitrification rate in the tributaries as that estimated in the main stem,
it is predicted that nitrate concentrations will exceed the limits set in the proposed Tukituki Plan
Change in three tributaries – two affected by point source waste discharges and intensive farming,
and one only affected by intensive farming. Denitrification has not been studied in the tributaries,
but the ‘worst-case’ assumption is that denitrification in the tributaries is zero. Making this
assumption, the model predicts only a slight increase in the number of exceedances, compared with
predictions assuming the same denitrification rate in the tributaries as that estimated in the main
stem. The reason for the increase being small is that the nitrate limits apply to the annual median
and 95th percentile concentrations, which are largely determined by winter high flows when
denitrification has little effect on nitrate concentrations. Nevertheless, it is recommended that field
investigations be undertaken to measure denitrification rates in the tributaries and compare them
with rates in the main stem in order to refine nitrate predictions in the tributaries where ‘hot spots’
of high concentration occur.
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Additional nitrogen mitigation may be required in some sub-catchments to avoid nitrate toxicity
problems. In the earlier TRIM1 study (Rutherford et al. 2012) it was shown that nitrogen mitigation
scenarios had the potential to decrease nitrogen losses leaving the Ruataniwha Basin from 1,615 t y-1
(Scenario B) to 1,480 t y-1 (Scenario C) – a reduction of 8%. Nitrogen reductions of this scale may be
sufficient to ensure that toxicity limits are not exceeded in some sub-catchments, although further
modelling is required to confirm this. If cost-effective nitrogen mitigation measures are unable to
ensure that toxicity limits are not exceeded then it may be necessary to restrict the types of
agriculture that will be permitted in some of the more sensitive sub-catchments.
In the scenarios modelled, the land use changes are those determined by Macfarlane Rural Business
based on a land use capability and economic analysis. Other mixes of land use are possible. An
earlier study (MacKay in Rutherford et al. 2012) investigated an alternative scenario in which dairy
and intensive arable were extended by a further 5,450 ha reducing sheep and beef extensive,
orchard and vineyard by the corresponding area. This translated to an increase in N losses of 100 t y-
1 from 3,060 t y-1 to 3,160 t y-1 which would have a negligibly small impact on the river.
Unmitigated P losses would be expected to increase by a similar, very small percentage.
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13 GROUNDWATER – DRINKING WATER MODELLING
A study of groundwater and the potential for nitrogen loss to drinking water for Zones A to D was
undertaken by HBRC Science Group (HBRC Science, May 2013).
The report notes that increased irrigation generally favours intensification of farming practices,
which increases the potential for nitrogen loss to groundwater through leaching. As a consequence,
adverse impacts on groundwater quality may be anticipated, in particular from increasing nitrate
concentrations.
Contaminant transport modelling was used to explore the fate of nitrogen in groundwater and help
identify areas where greatest risk of nitrate contamination is likely. The modelling used a three-
dimensional groundwater flow model (Baalousha, 2009, 2010) to provide input to a solute transport
model (Zheng, C. and Wang, 1999), which was used to simulate advection (horizontal and vertical
movement) and dispersion (dilution) within the aquifer.
The concentrations of nitrate in the aquifer recharge (a key transport model input) were prepared by
NIWA (NIWA 2013b), from leaching losses predicted for future land use. Groundwater flow and
contaminant transport models were run for a 35 year period starting in 2017, the date proposed for
commencement of the irrigation scheme.
The contaminant transport model predicts the likely concentration of a solute (in this case nitrate),
at any point within the model domain and at any time within the model timeframe. Three
groundwater layers were defined in the model in terms of depth.
The modelling process predicted:
• Concentrations were predicted to increase in all three groundwater layers over time.
• Highest nitrate concentrations were predicted in layer 1 (shallow groundwater).
• In general, the predicted nitrate concentrations are below the Maximum Acceptable Value
MAV.
• Nitrate concentrations were likely to exceed the (MAV) of the New Zealand Drinking Water
Guidelines (11.3 mg/L as nitrate-N) at three locations.
• The maximum nitrate concentration predicted is 16.4 mg/L, likely to occur 35 years from the
start of the simulation.
It must be noted that groundwater attenuation was not considered in this modelling, which is
conservative approach (i.e. predicts a worst-case scenario for nitrogen reduction).
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Although this approach is suitable to identify areas where there is a risk of exceeding the NZ Drinking
Water Guidelines (in certain isolated areas where slightly elevated nitrate concentrations are
predicted), there are significant uncertainties involved in this study, as in all solute modelling
approaches. Therefore, the model-derived estimates of likely future nitrate concentrations should be
used qualitatively to guide monitoring and management of future land use intensification and
related groundwater nitrogen concentrations. The monitoring activities will provide data to validate
the model and will confirm areas where nitrate leaching is occurring and the extent and magnitude
of any groundwater contamination. If necessary, mitigation strategies may be developed in
response to land use change and groundwater contamination.
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14 EFFECTS ASSESSMENT METHODOLOGY
14.1 Assessment Methodology
This AEE is based on a comprehensive suite of studies that HBRIC Ltd has commissioned in relation to
the Scheme (referenced in Table 1.8.1 to 1.8.3 in Section 1.8 of this AEE, and presented on the
attached CD-Rom).
The effects which have been assessed and which are covered in the following sections of the AEE
are:
14.1.1 Water Quality Assessments
Section 15 Reservoir water quality effects on Receiving Environment
14.1.2 Ecology Assessments
Section 16 Aquatic Ecology
Section 17 Terrestrial Ecology
14.1.3 Cultural Social and Recreational Assessment Reports
Section 18 Cultural Impacts
Section 19 Social Impacts
Section 20 Recreation Assessment
14.1.4 Construction, Landscape and Operations Assessment Reports
Section 21 Road Infrastructure and Traffic
Section 22 Noise Effects
Section 24 Historical Heritage / Archaeological Assessment
Section 25 Landscape and Visual Effects
Section 26 Sedimentation Effects
Section 27 Dam Break Study
14.1.5 Economic Assessment Reports
Section 23 Regional Economics
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The effects assessment reports follow a structured assessment methodology, which addresses the
following matters:
• Potential environmental effects
• Assessments undertaken
• Results of assessments
• Suggested approach for effects identified.
The results outlined in each of the assessment sections that follow are the executive summaries of
the Assessment Reports prepared for this AEE.
It is important to note that for consistency and accuracy the key findings of each of the Assessment
Reports are set out in the words of the respective authors, and have not been adapted or
paraphrased in the AEE, except where minor tense, referencing and wording changes have been
needed to assist readability, or where recommendations from the study authors have been
converted to firm commitments by the applicant.
The Assessment Reports form part of this AEE.
For more detail on the various assessment areas readers are directed to each of the specific reports
contained on the CD-Rom.
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15 EFFECTS OF RESERVOIR WATER QUALITY ON RECEIVING WATERS
An assessment of water quality effects was undertaken, and is discussed in a report prepared by
NIWA (Reservoir Water Quality – NIWA, May 2013b).
15.1 Potential Environmental Effects
The major effect of constructing a dam on the Makaroro River will be a change in flow regime in the
river below the dam from a natural high-low response to rainfall events to a more regulated flow
without extreme flood events. The use of the Makaroro reservoir, which forms behind the dam, as a
water supply for the proposed RWSS will cause changes in the water level in the reservoir and
different flow patterns in the downstream river, as defined in the Project Description33.
The water in the Makaroro reservoir will have a theoretical mean residence time of about 164 days,
based on the full volume of 90 million cubic metres and a proposed mean annual discharge of 6.342
cubic metres per second (Tonkin & Taylor data provided for the Feasibility Study34). This residence
time will delay the movement of sediment down the river channel by causing the heavier rocks,
gravel and sand to deposit at the inflow end of the reservoir and allowing sufficient time for the finer
particles to settle to the lake bed as the water moves the 6 km downstream to the dam wall and
outtake structures. This will substantially reduce the sediment load and produce higher clarity water
downstream of the dam.
The residence time will also allow the surface waters in the lake to become warmer than the inflow
river in winter and consequently the downstream river will be slightly warmer than it would naturally
be without the reservoir. Conversely, in summer the water temperature in the reservoir will be
cooler than the midday temperatures in the inflow river but warmer than the night time river
temperatures. This “thermal damping” will result in less variability in temperature than would
otherwise occur in the river downstream of the dam.
15.2 Assessments Undertaken
The assessment undertaken required characterisation of the predicted water quality in the proposed
Makaroro reservoir including:
• Expected physio-chemical characteristics of the water within, and discharged from the
reservoir
33 See Tonkin & Taylor (May 2013a) 34 Ruataniwha Water Storage Project - Feasibility Report to Council - Report No. WI 12-24 September 2012
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• Suitability of reservoir water quality for aquatic life, recreation and other uses
• Effects of removing versus retaining vegetation within reservoir extent
• Other considerations/recommendations regarding future dam site management before,
during and after dam establishment
• Further investigations/information that may be required to characterise reservoir water
quality.
To achieve this, the proposed reservoir was modelled using the coupled hydrodynamic-ecological
model DYRESM-CAEDYM to simulate hydrological, hydrodynamic and water quality for several
operating regimes. Expected bathymetry of the completed reservoir and flow data in the Makaroro
River were provided by Tonkin & Taylor Limited. Meteorological and climate data were obtained
from five of NIWA’s Virtual Climate Network Stations (VCNS) over the reservoir site and catchment,
as well as national Meteorological climate stations at Dannevirke and the Takapau Plains. Water
quality data for the Makaroro River were obtained from the NIWA National Rivers Water Quality
Network (NRWQN) monitoring site at Burnt Bridge. Additional parameters used in the model were
obtained from literature values and other studies producing similar simulations. These data were
applied to the DYRESM-CAEDYM model which was run with a daily step interval for the 5-year period
2000 to 2005.
Because the Makaroro reservoir does not exist, the model was unable to be calibrated against
empirical observations using statistical measures of model performance. Rather, the calibration for
sensitive parameters during the setup of the model was based on a combination of expert
knowledge, coefficients from other model applications, and values from literature. Consequently,
predictions and assessments use best scientific practice based on the available data provided.
Assumptions made in the modelling include no changes to land use in the catchment that would
increase nutrient loads to the Makaroro River and reservoir and that land clearance for production
forestry and other activities would be managed to keep sediment erosion to a minimum.
Initial model scenarios used operating regimes where a mean flow of around 6 cubic metres per
second was drawn from outtake valves set at either 455.5 m relative level (RL) (upper) or 426 m RL
(lower) with additional compensation water of about 1.23 cumecs being drawn from the toe of the
dam at 395 m RL. These modelling results indicated that the upper and lower outtake levels resulted
in selective draw-induced stratification at the draw depth. Water quality above the draw depth was
generally good but below the draw depth the water quality was poor, and would become anoxic for
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extended periods. It was concluded that selective draw from as deep in the lake as possible would
greatly improve the water quality in the reservoir.
This was tested with three new model scenarios:
• M1: main draw depth set at 405 m RL (allows 10 m deep sediment accumulation below the
draw depth)
• M2: main draw depth set at 443 m RL (has 48 m water depth below the draw depth)
• M3: minimum base flow of 1.228 cumecs drawn from 405 m RL and the remainder, about
5.1 cumecs being drawn from the 443 m RL outtake.
15.3 Results of Assessment
The presence of organic matter remaining within the reservoir extent at the time of construction was
found to cause oxygen depletion due to natural decomposition processes for several years after the
reservoir is first filled. As the organic matter was consumed over time, the extent of the oxygen
depletion reduced. While there was a small reduction in the time required to reduce the oxygen
depletion by removing the vegetation within the reservoir extent before filling, the costs of removing
the vegetation would be great and there would be areas of the reservoir extent where it would be
impractical.
Additional considerations were the management of the reservoir catchment to eliminate
unnecessary soil erosion due to land slippage following land clearance and future logging operations
for production forest.
In general, modelling showed that the water quality in the Makaroro reservoir was likely to be
similar to water quality of the inflow water although biogeochemical processes that occur naturally
in lakes may change the relative concentrations of some parameters. Seasonal changes followed the
natural cycles found in other deep lakes with the water column being fully mixed and well
oxygenated in winter but thermally stratified during summer. The depth of stratification was strongly
affected by the draw depth with oxygen depletion in the bottom waters, unless an aeration system
was used.
Scenario M1 produced the best water quality with less than 0.25% of the volume of the reservoir
(when full) becoming anoxic. Aeration may be required in some years with this scenario.
Scenario M2 produced the worst water quality with an estimated 21% of the total lake volume
becoming anoxic during summer stratification. Because of the large volume of stagnant water below
the draw-induced stratification depth, the modelling indicated that under this scenario the reservoir
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may not mix in some years. This would compound the issues of nutrient release from the sediments
in the bottom waters and could stimulate substantial algal blooms in the year when the reservoir
water column did mix. Aeration would be required with this scenario.
Scenario M3 produced an intermediate water quality with anoxia below the 405 m RL outtake (as in
scenario M1) and progressive oxygen depletion below the 443 m RL outtake eventually becoming
anoxic by mid-summer in some years. Aeration would be required with this scenario.
The M1 scenario model showed that nutrient concentrations were likely to be low in the upper
water column during summer but were likely to increase following winter mixing, and were likely to
support a low level of phytoplankton (free floating algae) in the upper water column in spring. With
low phytoplankton levels and low suspended solids concentrations from sediment, the water clarity
was likely to be high. Overall, the expectation was for the Makaroro reservoir to have a trophic level
classification of oligotrophic to mesotrophic.
15.4 Suggested Approach for Effects Identified
The Feasibility Study modelling found that scenario M1 produced the best water quality in the lake
with the least oxygen depletion in the bottom of the reservoir. Consequently, Scenario M1 is the
recommended option for the Makaroro reservoir operation regime.
It is also recognised that there are likely to be a few years after first filling when the bottom waters
will develop anoxia, before the reservoir stabilises. The proposed conditions provide for that an
aeration system to be installed in the bottom of the reservoir near the dam wall to provide water
column mixing and reduce the effect of or prevent anoxia.
The water quality in the reservoir is dependent on the quality of water entering the reservoir.
Sediment is a major pollutant of freshwater as is nutrient runoff from farming. It is recommended
that management strategies are developed for the reservoir catchment to reduce the incidence of
erosion that could exacerbate sediment accumulation in the reservoir, and to control land use
changes, including farming intensification, that could enhance nutrient runoff into the Makaroro
River and the reservoir.
The proposed conditions provide that a routine monitoring programme will be implemented on the
Makaroro reservoir to facilitate adaptive management strategies for the reservoir. Of critical
importance is the monitoring of temperature and dissolved oxygen (DO) at all depths in the reservoir
water column in order to manage the aeration system and thereby keep the DO concentration above
the minimum required for fish, i.e., 5 mg/L. A recommended aeration activation threshold and
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monitoring regime for the aeration system is provided in this report and this has been adopted in the
proposed conditions.
It is also important to have a monitoring programme that will provide basic water quality
information on the water in the reservoir in order to assess trophic condition and change over time.
Without this type of information it is not possible to detect changes in the reservoir water quality
that will allow management strategies to be developed and implemented in a timely manner.
While the Feasibility Study35 found that scenario M1 produced the best water quality and was
therefore the recommended option, subsequent hydrological modelling produced a new operating
regime (Scenario 3-28M) defined in the Project Description Report (Tonkin & Taylor, May 2013a).
Scenario 3-28M will allow water levels in the proposed Makaroro reservoir to be lower more often
than in Scenario M1 in most years. However, the lower levels indicated from the Scenario 3-28M
modelling are well within the range of water levels modelled for Scenario M1.
Consequently, provided the main draw depth for water is kept as deep as possible in the reservoir,
nominally at 405 m RL, the change in operating regime is unlikely to have more than a minor effect
on the lake water quality and thus the quality of the water discharged to the downstream river.
Further hydrological modelling was undertaken following the release of the Final Draft (March 2013)
suite of documents, which superseded scenario 3-28M described above. The outcomes of this
modelling with regards to lake level behaviour are presented in Figure 3.8 of the Project Description
(Tonkin & Taylor, May 2013a). Visual examination of this plot indicates very minor differences with
the 3-28M scenario described below and the conclusions drawn above in relation to the 3-28M
scenario are also valid for this latest scenario in the May 2013 Project Description Report.
35 ibid
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16 AQUATIC ECOLOGY
HBRIC Ltd engaged the Cawthron Institute (Cawthron) to review the Tukituki catchment’s aquatic
values, summarise the state of the existing environment, provide an assessment of effects on aquatic
ecology as a result of the Scheme, and identify mitigation and monitoring options.
The report - Aquatic Ecology Assessment (Cawthron, May 2013) is an updated and revised version of
the initial assessment of effects on aquatic ecology report that was prepared as part of the feasibility
stage of the Scheme (Young et al. 2012) and assesses the effects of the Scheme as described in the
Project Description (Tonkin & Taylor, May 2013a).
Values that apply to the whole of the Tukituki Catchment include: life supporting capacity, mauri,
contact recreation, water use (quality and economic), and fish passage.
Values that may vary across the catchment include: natural state, wetlands, riverine bird habitat,
inanga spawning, native fish habitat, trout spawning and habitat and contact recreation (amenity).
16.1 Potential Environmental Effects
The key potential effects of the construction and operation of the Scheme on aquatic ecology and
associated values are:
• Disturbance of the riverbed during construction and associated mobilisation of sediment
that could influence water clarity and have effects on periphyton, invertebrates and fish
(both native and introduced species)
• Effects of changes in bed geomorphology downstream of the dam on periphyton,
invertebrates and fish
• Effects on water quality associated with water storage within the proposed reservoir
• Blockage/interruption of upstream and downstream fish passage by the dam
• Permanent loss of riverine habitat resulting from inundation by the proposed reservoir;
• Reductions in the quantity and quality of spawning habitat for rainbow trout
• Changes to angling opportunities
• Changes in water quality associated with changes in the flow regime downstream of the dam
• Changes in periphyton abundance and distribution as a result of changes in the flow regime
• Effects of changes in the flow regime downstream of the dam (including short-term
fluctuating flows associated with changes in irrigation demand and hydro-peaking) on
habitat availability for invertebrates and fish
• Effects of flow changes on fish stranding
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• Diversion of fish into the water distribution network at the irrigation intake
• Instream and riparian habitat disturbance associated with changes in land use on the
Ruataniwha Plain associated with the Scheme
• Changes in water quality and effects on periphyton, invertebrates and fish associated with
changes in land use.
16.2 Assessments Undertaken
A combination of existing data, models, interviews, field studies and literature reviews were used to
identify the key values associated with the Tukituki catchment and the state of the existing
environment. Similarly, our assessment of effects of the Scheme was conducted using the
information gathered on the state of the existing environment, modelling of how water quality and
instream habitat are affected by changes to the flow regime, and guidelines/knowledge associated
with sediment effects, periphyton, invertebrate and fish habitat requirements. Concurrent work on
water quality in the reservoir (NIWA, May 2013c), predicted changes to the flow regime (Tonkin &
Taylor 2011; HBRC Science May 2013a; Aquanet, May 2013), predicted changes to sediment
transport and geomorphology (Tonkin & Taylor, May 2013b), surveys of trout spawning and juvenile
trout density (Maclean 2011; 2012), predicted effects of land use on water quality and periphyton
(NIWA, May 2013a, b) and new information on nitrate toxicity thresholds (Hickey 2013a, b) have
been incorporated into our assessments.
16.3 Results of Assessments
Outlined below are the results of the Cawthron Assessment:
• Effects of construction on water quality are predicted to reduce rapidly once the working site
is adequately stabilised. However, deposition of mobilised sediment downstream of the
proposed dam site may have longer term effects that take 6-months to one year for full
recovery. The effects will be most marked close to the proposed dam site and have less
influence downstream of the Waipawa and Tukituki confluences.
• The reduction in bed aggradation, due to sediment retention in the proposed dam, is likely
to result in a reduction of gravel extraction from the channel, and associated reduction in
habitat disturbance. This is likely to have a net benefit to the aquatic ecosystem. The
coarsening of the bed substrate is also likely to have a net benefit for many species of native
fish which prefer coarse substrates. However, bed coarsening and armouring will potentially
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increase the suitability of habitat for nuisance periphyton growth and reduce the availability
of suitable spawning gravels for rainbow trout downstream of the dam.
• Modelling (NIWA, May 2013c) predicts that changes in water quality associated with storage
of water within the reservoir are expected to be relatively minor. Water quality will be
continuously monitored and an aerator is proposed to be installed near the upstream face of
the dam to manage any unforeseen changes in water quality. Problems with levels of
dissolved oxygen, nutrients and sediment released downstream from the reservoir are not
expected.
• Movement of fish, both upstream and downstream, past the dam will be affected by the
presence of the dam. The seven migratory native fish species currently present in the vicinity
of the dam are unlikely to sustain self-supporting populations above the dam. Consequently,
these species would be lost from the fish community above the dam over time, unless fish
passage is provided. While the loss of the seven migratory species within the Makaroro River
upstream of the proposed dam would restrict the geographic range of these species within
the wider Tukituki catchment, the loss of the upper Makaroro River populations of these
species is not expected to result in a significant increase to the threat of extinction of these
species from elsewhere in the catchment. Nevertheless habitat loss for any indigenous or
valued species is not desirable, so the report recommends that an upstream and
downstream trap and transfer programme and habitat enhancement initiatives be used to
mitigate the effects.
• The creation of a 372 ha reservoir will result in a loss of approximately 7 km of flowing water
habitats. Some of the native fish species currently found in the river habitat are also
commonly found in still water habitats and will be able to use the newly formed lake-like
habitat of the reservoir. However, other species (e.g. torrentfish, bluegill bully, redfin bully,
Cran’s bully, and dwarf galaxias) are unlikely to use the still-water habitat in the reservoir,
and for these species the inundation of streams in this area will represent a loss of habitat.
Many of the invertebrate species found in the Makaroro River are also unlikely to use the
still water habitat in the reservoir, although invertebrates that prefer still water will replace
them to some extent and provide food for fish living in the reservoir.
• A trout population of between 1000-2000 adult fish is likely to develop in the reservoir and
support a full season fishery for small rainbow trout, rather than the current early and late
season fishery for post- or pre-spawning rainbow trout of average size. Juvenile trout
production from these adult trout may be enhanced compared with the status quo as a
result of the reservoir. It is very likely that some of these juvenile trout will successfully pass
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downstream through the turbines or over the spillway and make a substantial contribution
to the fishery in the Waipawa and Tukituki rivers. The benefits to be derived from the
juvenile trout that will pass downstream are difficult to quantify precisely and hence so are
the overall effects on the trout fishery of the inundation and loss of spawning habitat
associated with the reservoir and the blockage of the spawning migration from downstream
caused by the dam.
• The Scheme will result in substantial changes to the flow regime downstream of the dam. In
the reach between the dam and the irrigation intake there will be higher flows in the
summer irrigation period and lower flows in late autumn and winter. Flood frequency will be
reduced particularly during late autumn and winter when floods will be captured within the
refilling reservoir. Downstream of the irrigation intake, there will be a general reduction in
median flows throughout the year as a result of the Scheme, but an increase in the lowest
flows. The changes in flow are most significant in the Makaroro and Waipawa rivers.
Downstream in the Tukituki River, the changes in the flow regime are smaller because flow
inputs from the upper Tukituki River and other tributaries are largely unaffected by the
Scheme.
• Increases to low flows are predicted to occur when the Scheme is in operation, particularly if
current surface and ground water abstractions are ‘migrated’ to the Scheme water (HBRC
Science, May 2013a).
• At times, the water temperatures within the Tukituki catchment currently approach levels
that will begin to stress sensitive aquatic life. The Scheme will result in higher summer flows
and cooler summer water temperatures between the dam and the irrigation intake because
of the flow releases of cool water sourced from the dam. Therefore, this is expected to be a
net benefit to the river ecosystem in these reaches. Downstream of the irrigation intake,
there will be a decrease in median flows, but higher minimum flows than occurs under the
status quo. Any effects of changes to the flow regime itself on water temperature will be at
most, minor (predictions of no change to mean temperature and < 0.5 °C increase in
maximum temperature).
• The general reduction in median flows downstream of the irrigation intake will reduce the
capacity of the river to dilute contaminants at moderate flows. However, in contrast the
general increase in minimum flows will result in an increase in dilution of contaminants at
low flows.
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• The change in the flow regime in the Makaroro River will provide better hydraulic conditions
for the growth of undesirable long and short filamentous algae on the river bed, but reduce
habitat suitability for desirable diatoms. This is considered to be a net negative effect on the
river ecosystem, but periphyton growth is not expected to be problematic in this reach
because nutrient concentrations are relatively low. Further downstream and below the
irrigation intake, the changes in flow regime on habitat suitability for different components
of the periphyton community are mixed, with increases in suitability in some months and
decreases or no change in other months.
• The frequency of flows large enough to flush periphyton from the river bed is more
important in controlling periphyton biomass than general hydraulic suitability for
periphyton. The frequency of flows capable of flushing periphyton will be reduced,
particularly during the irrigation season and during late autumn/winter when the reservoir
will be refilling. However, the Scheme design has incorporated the capacity for four flushing
flows of up to 30 m3/s to be released from the dam per year to aid the management of
periphyton growth in reaches downstream of the dam, including the lower Tukituki River.
These flushing flows will be very effective in the Makaroro and Waipawa rivers downstream
of the dam. However, evidence suggests that they are also likely to provide significant
benefits in the Tukituki River below the Waipawa confluence, particularly if the flow releases
are timed to coincide with small natural freshes from the upper Waipawa and upper Tukituki
rivers. Therefore, nuisance periphyton accumulations will be able to be managed to a large
extent using these flushing flows. This is a clear environmental benefit of the Scheme over
the status quo and will help to meet the periphyton objectives of the proposed Change 6.
• The broad-scale changes to the flow regime will result in both gains and losses in habitat
suitability for invertebrate species. While there will be changes to the composition of
invertebrate communities in the Makaroro as a result of changes to the flow regime, the
predicted habitat losses will not affect the viability of populations below the dam down into
the Tukituki system. The largest effect of the proposed flow regime on the invertebrate
community relates to the regular short-term fluctuations in flow that result from changes in
irrigation demand during the summer and from hydro-peaking during winter. These flow
fluctuations will have negative effects on habitat suitability for species with limited mobility.
Margins of the channel that are suitable at the high end of the flow fluctuation cycle will dry
out or become too shallow during the low flow part of the fluctuating cycle, while areas in
mid-channel that are suitable at the low end of the fluctuating cycle may become too fast at
the high end of the cycle. These flow fluctuations are predicted to result in a 50% reduction
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in habitat availability for invertebrates (and up to a 100% reduction i.e. complete removal in
habitat availability for rainbow trout spawning) in the Makaroro and Waipawa rivers
downstream of the proposed dam. The effects in the Tukituki River will be much lower due
to flow contributions from other parts of the catchment making the relative change in flow
smaller, and downstream attenuation of the flow fluctuations themselves. It should be noted
however, that these predictions do not take into account the effects of natural flow
fluctuations and therefore are probably an overestimate.
• The degree to which fish abundance and/or growth rate may be affected by this reduction in
invertebrate habitat is uncertain, because it depends on whether fish are currently food
limited. But given that the predicted reduction in invertebrate habitat is potentially large
(around 50% for Deleatidium which represents a riverine trout’s main food source), this may
have some adverse effect on food intake by fish -- with a consequent adverse effect on
growth rates and/or survival.
• Fluctuations in flow that result from changes in irrigation demand during the summer and
from hydro-peaking during winter may result in relatively fast declines in flow within the
Makaroro River at times, potentially resulting in fish stranding. However, the shape of the
Makaroro River channel means that there will be limited areas where isolated pools are
likely to be formed by rapid dewatering. Therefore, the effects of flow reductions on fish
stranding in this reach are expected to be minor.
• The main potential effect of the upper irrigation intake structure is the potential
entrainment of fish into the canal system. A rockfill infiltration bund is currently proposed to
act as a fish screen at the proposed upper intake. The efficacy of this bund as a screen will be
dependent on the size of the packing fill used to construct the bund because the fill needs to
emulate 3 mm mesh openings in a metal screen. Tonkin & Taylor have confirmed that the
packing fill will meet this intent and therefore the effects on fish entrainment should be
largely avoided.
• Possible future land use changes may mean that there will be more heavy animals (i.e. cattle
rather than sheep) and higher stocking rates on the Ruataniwha Plains. These changes to
stock type and stocking rate have the potential to increase the amount of physical damage
to instream habitat and the riparian margins of streams flowing through the irrigated areas if
stock are not excluded from waterways. It is recommended that stock exclusion be an
integral part of the overall Scheme design, and in any event it is noted that stock exclusion is
a key rule in HBRC’s Change 6.
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• Modelling of a future land use scenario with no on-farm mitigation predicted that nitrogen
and phosphorus inputs for the whole catchment would increase by 32% and 6%, respectively
as a result of the land use intensification associated with the Scheme. Nitrogen and
phosphorus losses within the irrigation command area are predicted to increase by an
average of 81% and 41% respectively (NIWA, May 2013b). The resulting increase in
phosphorus concentration was predicted to result in faster periphyton growth and higher
peak biomasses of periphyton in the lower Waipawa and Tukituki rivers. However, the
Scheme is now being progressed on a phosphorus neutral basis, compared with a 2013
baseline. At a whole catchment scale, modelling indicates that fencing to exclude stock from
streams and the optimal use of phosphorus fertiliser are predicted to offset the 6% increase
in phosphorus losses and make the RWSS close to phosphorus-neutral overall (predicted 1%
increase). However, within the irrigation command area, land use change with mitigation is
still predicted to increase phosphorus losses by 7% relative to pre-irrigation levels –
significantly lower than the predicted 41% predicted without any mitigation, but still not
‘phosphorus-neutral’. The modelling does not capture all of the benefits of stock exclusion,
but even so, additional mitigation measures may be required in some irrigated sub-
catchments for them to be ‘phosphorus-neutral’ (NIWA, May 2013b).
• Prior to construction of the Scheme, the discharges of sewage from Waipukurau and
Waipawa will be significantly reduced as part of their consent conditions. This diversion of
phosphorus load to the river will reduce periphyton growth rates and peak biomasses in the
lower Tukituki and Waipawa rivers.
• The combination of phosphorus neutral status and reduced inputs of phosphorus from the
Waipukurau/Waipawa waste water treatement plants is predicted to result in significant
reductions in annual average periphyton biomass, and less frequent periods of high biomass.
Nevertheless, during periods of prolonged low flow, periphyton biomass will continue to
reach high levels (NIWA, May 2013b). The proposed flushing flows associated with the
Scheme are expected to provide additional reduction in the incidence of high periphyton
biomass by interrupting the periods of biomass accumulation during prolonged summer low
flows.
• High concentrations of nitrate nitrogen can be toxic to aquatic life. Land use changes
associated with the Scheme are predicted to increase nitrate concentrations significantly in
tributaries draining the irrigation command areas. It is predicted that without mitigation
nitrate concentrations will exceed the limits set in the proposed Tukituki Plan Change in five
of the tributaries – three affected by point source waste discharges and intensive farming,
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and the remainder affected by intensive farming only (NIWA, May 2013b). To address this
issue additional monitoring will be required and particular attention will need to be given to
sites that are predicted to be close to, or beyond, the proposed limits. Management actions
aimed at reducing nitrogen leaching will be required in any areas that are over the limit to
avoid the risk of nitrate toxicity problems. If cost-effective nitrogen mitigation measures are
unable to ensure that toxicity limits are not exceeded then it may be necessary to restrict the
types of agriculture that will be permitted in some, sensitive, sub-catchments.
16.4 Suggested Approach for Effects Identified
A number of initiatives are recommended to mitigate potential adverse effects of the Scheme on
aquatic ecology. These include:
• An upstream and downstream trap and transfer programme that will enable migratory
native fish to access habitat upstream of the proposed dam, and enable mature longfin eels
to move downstream and complete their life cycle.
• Pre and post-construction monitoring of the age-structure of the eel population upstream of
the dam to ensure that the trap and transfer programme is enabling successful recruitment.
• Post-construction monitoring of the efficacy of the rock-fill infiltration bund at the upper
irrigation intake as a fish screen.
We recommend that these initiatives could be implemented alongside five broad restoration and
enhancement packages. These include:
Ruataniwha Reservoir Restoration Buffer and Catchment Enhancement Zone:
This is as proposed in the Integrated Offset and Mitigation Approach report (HBRIC, May 2013f). In
terms of aquatic ecology the key objectives of this initiative would be to protect and enhance the
aquatic habitat within the upper Makaroro River above the dam and other reservoir tributaries such
as Dutch Creek. This would also help to limit inputs of nutrients and sediment to the proposed
reservoir and maintain reservoir water quality, although this effect would be minor.
Ruataniwha Riparian Enhancement Zone (River Halo Project):
Again, this is as proposed in the Integrated Offset and Mitigation Approach report (HBRIC, May
2013f). The focus of this initiative should be on protection of riparian habitats alongside the
Makaroro and Waipawa rivers that are affected by flow fluctuations resulting from the Scheme.
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Ruataniwha Threatened Species Habitat Enhancement
This initiative focusses on fostering habitat protection/enhancement for bats throughout Hawke’s
Bay, terrestrial predator trapping to enhance biodiversity values within the upper Makaroro
Catchment and downstream to the upper intake structure, and the upstream and downstream trap
and transfer programme for native fish.
Ruataniwha Plains Spring-fed stream Enhancement and Priority Sub-Catchment Phosphorus
Mitigation
The changes in land use associated with the proposed Scheme will have to be managed carefully.
The objectives for this initiative are to protect and enhance the spring-fed streams and other
waterways that drain the lower Ruataniwha Plains (e.g. tributaries of the lower Mangaonuku,
Kahahakuri, Waipawamate, Black Stream, Maharakeke, Tukipo and presumably many unnamed
ones). These streams provide good habitat for eels and some other native fish species and also
appear to be important locations for spawning and juvenile trout rearing. The package would
involve support for landowners with fencing, replanting and ongoing riparian maintenance and legal
protection and fencing of any existing wetlands. A focus will be on ensuring that stock are
permanently excluded from waterways and sediment/phosphorus inputs are restricted. This project
is presented in more detail in the Integrated Offset and Mitigation Approach report (HBRIC, May
2013f)
Modelling indicates that with appropriate mitigation the Scheme can be developed on a phosphorus-
neutral basis and therefore if all the mitigation and rehabilitation efforts and measures are in place,
the Scheme will have relatively minor effects on the aquatic ecosystem and the Tukituki Catchment
will continue to support the current wide range of values.
Restoration of Old Waipawa River Bed / Papanui Stream
The objective of this package is to rehabilitate and enhance water quality and stream habitat in the
bed of the old Waipawa River / Papanui Stream subsequent to any works required to meet Zone M
irrigation requirements. This will involve funding to contribute to fencing, planting and wetland
creation along the riparian margins of the stream.
At a whole-catchment scale, modelling indicates that with stock exclusion and optimal use of
phosphorus fertiliser the Scheme can be developed on a near ‘phosphorus-neutral’ basis. Provided
the ‘phosphorus-neutral’ status can be achieved in all sub-catchments, the provision of augmented
flushing flows, as now proposed, should contribute to reducing periphyton growth in the lower
Waipawa and Tukituki rivers. However, within the irrigation command area it appears likely that
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careful monitoring, additional mitigation measures, and perhaps restrictions on the types of
agriculture permitted in some sensitive subcatchments will be required to avoid increases in
phosphorus concentrations and exceedances of proposed nitrate toxicity limits in some streams
draining the Ruataniwha Plains. If this can be achieved and if all the other mitigation and
rehabilitation efforts are in place, the Scheme will have relatively minor effects on the aquatic
ecosystem and the Tukituki will continue to support the current wide range of values.
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17 TERRESTRIAL ECOLOGY
Kessels & Associates conducted an ecological impact assessment of the Scheme and made
recommendations regarding measures to avoid, mitigate or offset potential adverse effects on
indigenous terrestrial fauna and flora species and their habitats. The focus of the assessment and
report (Kessels and Associates, May 2013) is on the reservoir and dam components of the Scheme,
although the assessment extends to the braided river ecosystems downstream of the dam and
reservoir.
17.1 Potential Environmental Effects
The potential ecological effects of the construction and operation of the Scheme on terrestrial
indigenous fauna and flora as assessed in the report are:
• A permanent loss of a variety of indigenous vegetation communities and braided river within
the reservoir,dam and spillway footprint area
• A permanent loss of a variety of feeding, roosting and breeding habitats (both exotic and
indigenous) for birds, lizards, bats and invertebrates
• Alteration of habitats for indigenous flora and fauna within and adjacent to braided river
ecosystems downstream of the dam and upstream water intake structure associated with
changes in sediment deposition rates, river flow patterns and changes in land use
• A change of habitat types on the margins of the reservoir due to changes in hydrology and
effects of seasonal and irrigation drawdown causing inundation and ebbing of the ‘lake’ edge
• Disturbance of remaining indigenous flora and fauna adjacent to the reservoir due to
potential increases in the recreational use of the reservoir and its margins.
17.2 Assessments Undertaken
Field assessments have been undertaken over the period of September 2011 to February 2013
within, and over areas potentially affected by, the proposed dam and reservoir components of the
Scheme. In addition, literature searches, data analysis, GIS mapping analysis and ecological
significance determination have also been undertaken during this period. Specifically, the
investigations have focussed on:
• Field Investigations to ground truth and refine vegetation maps and to assess whether any at
risk or threatened plants are in the affected areas
• Avifauna surveys to determine relative abundance of common indigenous and native birds
and to assess whether any at risk and/or threatened birds utilise the affected areas
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• Field investigations to confirm the level of importance of affected habitat for long-tailed bats
• Field investigations to confirm the importance of affected habitat for lizards, in particular to
identify the presence or absence of at risk and threatened species
• Field investigations to confirm the importance of affected habitat for invertebrates, in
particular to identify the presence or absence of at risk or threatened species
• An examination of the impact of habitat loss on functional landscape ecology values
• Potential effects of river morphology changes on terrestrial linked ecosystem values
• Recommendations for appropriate measures to avoid, remedy, mitigate, or offset for any
potential adverse effects identified.
17.3 Results of Assessment
The total area affected by flooding, the dam structure and spoil disposal is approximately 450.18 ha.
A total of 185.18 ha of ecologically significant indigenous vegetation and habitats would be flooded
by the proposed reservoir, or covered over by associated infrastructure including the dam structure,
new access tracks and soil disposal sites. This comprises of:
• 80.71 ha of mature and secondary indigenous forest (including a number of trees which
would be in excess of 300 years old)
• 2.69 ha of treeland
• 22.70 ha of secondary indigenous scrub
• 73.97 ha of gravel river bed
• 5.11 ha of wetland or seep zones.
One At-Risk plant species was found – red mistletoe.
A total of 38 bird species (11 endemic) were identified at the proposed reservoir locality during
formal field surveys. Of all individual birds formally observed 55% were native and 45% introduced.
Threatened or At Risk species comprise 2.5% of all observations, including one pair of nesting and
Nationally Vulnerable New Zealand bush falcon, and one adult banded dotterel with a chick.
Nationally ‘At Risk’ species detected were pied stilt, New Zealand pipit, black shag and North Island
fernbird.
Long-tailed bats were found throughout the proposed reservoir during an ultrasonic survey
completed between November 2011 and February 2012 and again between January and February
2013.
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Simultaneous surveys of the reservoir area and wider landscape showed that it is likely that bats are
resident and roosting within the reservoir area, and then move out into the wider landscape
throughout the night. Activity levels are higher within the reservoir zone when compared to the
wider landscape demonstrating the importance of this habitat for the bats, albeit evidence of a
discrete population within the wider landscape was obtained through the surveys.
Eleven lizard species are known from the southern Hawke’s Bay region or neighbouring areas of the
southern North Island. However, only one lizard was found during the field survey. This was a
southern North Island forest gecko. It is not classified as being a nationally At Risk or Threatened
species.
Targeted rapid surveys for terrestrial invertebrates were undertaken within the proposed reservoir
site in December 2011 and again in January 2012. In addition, passive detection devices have been
deployed and checked throughout the site from November 2011 until February 2013. Results
showed a rich diversity of insects and land snails. Two individuals of the ‘At Risk’ Hawke’s Bay tree
weta, Hemideina trewicki, have been discovered within the study area.
17.4 Suggested Approach for Effects Identified.
A number of measures are required to avoid or remedy potential adverse effects on terrestrial
ecology. These include:
• A bat management plan
• A pre-construction lizard survey and translocation plan
• Weed hygiene and surveillance
• Post-construction monitoring of key wader bird species within affected braided river habitat
and contingency habitat enhancement if adverse effects are shown to occur.
In addition to measures to avoid, remedy or directly mitigate for potentially affected flora and fauna,
three key Mitigation and Offset packages are recommended. These are:
Ruataniwha Reservoir Restoration Buffer and Catchment Enhancement Zone:
The objectives of this package are to:
• Re-create 46 ha of riparian margin with indigenous vegetation, which will provide habitats
and ecological linkages for a wide range of fauna and flora
• Restore and enhance at least 100 ha of marginal farmland and existing forest, scrub,
treeland, shrubland and wetland remnants within the sub-catchment above the dam to
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quickly improve existing habitat for flora and fauna, reinforce ecological linkages within the
landscape and provide refuge for species during and after the flooding process.
Ruataniwha Riparian Enhancement Zone (River Halo Project)
The objectives for this package are to:
• Control willows/lupins and other braided river weeds to maintain and enhance habitat for
wading birds, particularly banded dotterel, within the Waipawa and Makaroro Rivers. This
may also include fencing and restoring margins of the main stems of the two rivers where
required, in consultation with adjoining landowners. The primary target area for these
works would be high quality wading bird habitat
• Assist landowners with fencing, replanting (as required) and legally protecting existing areas
of wetlands, bush and scrub within or contiguous with the 1 km buffer (width) enhancement
zone.
Ruataniwha Threatened Species Habitat Enhancement
The objectives for this package are:
• Targeted assistance programme to foster research, advocacy and habitat
protection/enhancement for bats and their habitats throughout Hawke’s Bay
• Predator trapping programme to enhance the biodiversity values of indigenous forest areas
within the upper Makaroro River catchment and downstream of the dam structure to
Caldwell Road (principally focusing on blue duck and wader bird habitats, subject to results
of pre-construction blue duck survey and wader bird population survey)
• Trap and transfer programme focusing on native fish.
The above programmes would result in a number of significant benefits, including: Intensive,
targeted animal pest control over 1,100 ha of habitats within the Makaroro River catchment, 146 ha
of habitat recreation and enhancement around the new reservoir and within its sub-catchment;
assisting landowners to protect and manage over some 622 ha of bush, scrub, and wetland, and
approximately 314 ha of braided river habitat for wading birds within a corridor of the mid reaches
of the Waipawa and Makaroro Rivers; and contributing towards projects that will enhance the
knowledge of Threatened and At Risk species, as well as their habitats within the Hawke’s Bay
Region. In addition, Project E will re-create and restore wetlands in and along the Old Waipawa
River / Papanui Stream, providing additional compensation for the wetland ecosystem losses
associated with the Scheme.
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The mitigation recommendations contained within this report have been integrated into a separate
report entitled “Ruataniwha Water Storage Scheme – Proposed Integrated Mitigation and Offset
Approach” (HBRIC, May 2013f).
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18 CULTURAL IMPACT ASSESSMENT
18.1 Introduction
Cultural Impacts are assessed in two reports (Taiwhenua ō Tamatea & Taiwhenua ō Heretaunga -
June 2012) and (Taiwhenua ō Tamatea - April 2013). The first report was jointly commissioned for
the RWSS and Change 6 processes and deals with cultural values and uses in the whole catchment.
Section 5.2 of that report specifically addresses the RWSS and the text outlined in Section 18.2 to
18.5 below is taken from that section.
As discussed further in 28.6 a Mana Whenua Working Party was established to implement the key
recommendations regarding the RWSS contained in Taiwhenua ō Tamatea & Taiwhenua ō
Heretaunga - June 2012.
As part of the Mana Whenua Working Party process an additional Cultural Impact Assessment
Report was commissioned (Taiwhenua ō Tamatea, April 2013) which assessed the cultural effects of
Zone M which was brought into the Scheme after feasibility assessments were completed in 2012.
Section 18.6 below sets out the executive summary of the Addendum Report.
18.2 Involvement of Mana Whenua
Over the last few years, the HBRC and HBRIC Ltd have undertaken a pre-feasibility and feasibility
study to investigate potential dam sites within the Ruataniwha region. The initial CIA report was
commissioned in 2010 to investigate eight potential dam sites (Wakefield et al, 2010). The
supplementary report was commissioned in 2011, which narrowed the focus to two potential dam
sites on the Makaretu and Makaroro Rivers (Wakefield et al, 2011). The CIA reports identified
registered and unregistered wahi tapu and other cultural values likely to be adversely affected by the
location of the proposed sites. Another focus of the reports was to assess any cumulative effects on
the health state of the Tukituki River catchment in terms of tangata whenua relationship to cultural
values, mauri, water quality, indigenous biodiversity, and other concerns within the Tukituki
catchment. These two CIA reports focused primarily on the views of mana whenua within the
central Hawke’s Bay region associated with Te Taiwhenua ō Tamatea. The HBRC Maori standing
committee representatives strongly advocated for the involvement of Marae and Hapu from the
lower Tukituki River catchment. This resulted in a CIA report commissioned by the HBRC to be
undertaken by Te Taiwhenua ō Heretaunga and was completed in 2012 (Te Apatu & Moffat, 2012).
There was a single focus on the proposed dam site on the Makaroro River.
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The first CIA report identified several cultural values of importance to mana whenua and has formed
the foundation for the cultural values framework constructed for the Tukituki River catchment
cultural values and uses change plan. These cultural values were applied to the supplementary and
third CIA report completed. There was a broad description of tangata whenua cultural values and
their relationship to the Tukituki catchment and included: Te Ao Maori world views; Papatuanuku
earth mother; Kaitiakitanga responsibilities; the elements of nature; ki uta ki tai - Ruahine ranges:
headwaters, Ruataniwha plains and the lowlands of the Tukituki river mouth; Taonga Tuku Iho of nga
wai and the biodiversity values and mahinga kai resources within the Ruataniwha plains of
importance to tangata whenua.
Tangata whenua were asked their views on potential effects of cultural values, potential benefits and
costs and finally, their socio-economic aspirations for marae and hapu and the findings are briefly
outlined in the sections below.
18.3 First CIA Report – Overarching Issues
The relationship of cultural values to water flow regime and water quality focussed on the
headwaters as the source of mauri, waipuna/springs/aquifer and the effects of land use
intensification activities, Riparian areas, mahinga kai/biodiversity and indigenous species, river
mouth environment and the role of Kaitiakitanga.
There were no known wahi tapu sites registered or unregistered specifically located within any of the
eight originally proposed water storage sites. Potential issues associated with the proposed Tukituki
water storage dams outlined particular concerns with water flow management and water allocation,
water quality, land use activities and effects on water quality and water bed and river margins.
The findings from the first CIA study indicated that marae and hapu were cautious and uncertain on
what the potential benefits might be for Maori. There was a significant issue with the lack of
consultation that did not occur with marae/hapu during the pre-feasibility study. Most of the
recommendations made from Tangata whenua were focused around the HBRC (and then HBRIC Ltd)
consulting directly to follow-up on this CIA study and to discuss how the council would address the
issues and concerns highlighted in the report.
18.4 Supplementary CIA Report
The findings from the supplementary CIA report revealed there was some support in principle for the
proposed dam sites on the Makaretu and the Makaroro.
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The change from smaller dams to one large dam proposed on the Makaroro raised concerns on any
potential break in the dam which was likely to directly flood out the Waipawa district in particular.
Their preference was for smaller dams which they sought to discuss more directly with the HBRC.
There were concerns for the cumulative health effects from pollution, water quality, flows and over
allocation of water which needed to be mitigated.
There were unregistered wahi tapu/ wahi taonga which would require more discussion with tangata
whenua directly to ensure these sites were protected during subsequent stages of the Scheme study
development. There was also a need expressed for more discussion on potential social and
economic benefits for tangata whenua. With Waitangi Treaty claim negotiations still to be settled,
this was likely to highlight wider issues concerning co-management of the waterways within the
Ruataniwha region.
18.5 Lower Tukituki (Heretaunga) Specific Issues
Within the CIA report, there was a comprehensive overview of the historical and contemporary
issues raised for Heretaunga marae/hapu. Although these issues were related to the proposed dam
on the Makaroro, they are also relevant to how mana whenua cultural values relate to the whole of
the Tukituki River catchment. The executive summary of the CIA is reproduced below and provides a
deeper insight and understanding of their cultural values as they apply to the Tukituki River.
Ko Heretaunga Haukunui, Ararau, Haaro te Kaahu, Takoto Noa
Heretaunga - of the life-giving dew, of the hundred pathways, the vision of the far-sighted
hawk, left to us, the humble servants.
“Ko Heretaunga Haukunui, Ararau, Haaro te Kaahu, Takoto Noa” is a centuries old tribal whakataukī
(proverb), that is as relevant today as it was when it was first uttered. It has many layers from which
to identify and describe the tangata whenua (people of the land), acknowledging Maori and their
spiritual connection and birthplace of Heretaunga, the environment, and their relationship to each
other, and as such is the framework upon which this report is based.
It is a statement of mana whenua (authority, possession and spiritual connection to certain land),
and that in turn is the foundation that says nga hapu o Heretaunga (clans of the Heretaunga region),
are entitled to be equal partners at all levels of engagement, to be decision-makers for the future,
and to have guardianship of the whenua (land) and awa (waters), which cannot be broken.
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While appreciating the differences between the lower and upper Tukituki catchments, the hapu
residing in the lower Tukituki area do not separate the awa, and have cultural links right from the
headwaters to the river mouth.
Environmentally, tangata whenua see an awa as a whole entity whose parts are interdependent and
the health or well-being of any tributary, flora, fauna, birds, fish, or insect will be affected by the
health of the awa, and vice versa; and so too the well-being of the people.
Marae/ hapu (common village, clan or social order) feel very much a part of the river and see it as
their right, as tangata whenua, to be involved in its life. It is their duty as kaitiaki (guardians) to be
involved in protecting its mauri (life force, essence), and “Hurumanu” (with a bird’s-eye view)
reminds us that there must be an active role and participation in doing so. The questions arise, “Will
this be possible?” and “How?”
Many of the issues raised in this report are related to protecting the mauri of the river and its
environs, habitats and ecosystems. There have already been losses from a hugely modified river,
and it is of concern that further modification will render mahinga kai (traditional food gathering
sources or places), livelihoods, traditional practices, and recreation very much reduced, or even non-
existent - not only for marae/ hapu, but for other local communities, interest groups, and the
majority of whanau and families of the region.
Hapu wish to be involved at all levels of the process to ensure that the Maori world view is
represented, that they can fulfil their obligation as kaitiaki and that they are not marginalised or
excluded from prosperity. It is vital that they do not continue to suffer disconnection from their awa
as has happened in the past.
18.6 Zone M Addendum Report
The addendum report provides a cultural impact assessment of the proposed Zone M located within
the region starting from Waipawa, Otane, Pukehou and Te Whatuiāpiti areas of Central Hawke’s Bay.
The Hawke’s Bay Investment Company Limited (HBRIC Ltd) is proposing to deliver irrigation water to
Zone M of the RWSS by using the Old Waipawa Riverbed and the Papanui Stream as the primary
distribution mechanism/ headrace.
The tangata whenua from this area involve four marae: Mataweka, Tapairu, Pukehou and Te
Whatuiāpiti. The overwhelming response from tangata whenua is primarily concerned with the
protection of cultural values and to improving the mauri of their waterways. This includes the three
lakes known as ‘Ngā Puna a Tara’ within Pukehou, which have been in private ownership for many
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years. The Papanui Stream source flowed from the springs and as an outlet of Lake Roto-a-Tara.
Over the years the stream has been modified, re-diverted, narrowed and deepened, and most
alarmingly, shrunk in size and water velocity and polluted to the point of being ‘mauri-mate.’ The
HBRC and HBRIC Ltd acknowledge the Papanui Stream now has a ‘poor quality’ grading.
The Zone M concept is proposing to release the water from the Makaroro Dam to be re-diverted
along the Old Waipawa River Bed that was blocked off many years ago. Tangata whenua are
supportive of the opportunity to enhance the life supporting capacity of the river. The springs
located along the Waipawa River stretch close towards the township. It is a major concern for
tangata whenua who are hoping the increase in surface water from Walker road along the old
Waipawa River Bed will allow the ground water aquifer to replenish itself.
The council are seeking to develop riparian strips alongside the Papanui Stream. This is being
supported by the tangata whenua and viewed as an opportunity to enhance the fishery, habitats,
fauna and flora in the waterways.
Tangata whenua have raised some concerns over the lack of specific detail concerning the
construction of the piping systems, canals and to utilising the existing natural characteristics of the
Old Waipawa River Bed and the Papanui Stream. There is some perceived risk to wāhi tapu sites
located in close proximity to the Papanui Stream that will require further dialogue with the marae on
mitigation measures to protect these sites.
Tangata whenua have expressed scepticism on how the proposed Zone M concept will benefit the
four marae located within the region. The loss of water drained away for agricultural farming over
the years has also impacted on the ability of marae to access water from the waterways that used to
flow past their papakāinga (i.e., the springs, streams and lakes) which are now virtually non-existent
or are in poor health.
The CIA report has made a number of recommendations for HBRIC Ltd to consider and the four
marae in particular, are keen to dialogue directly with HBRIC Ltd to discuss their concerns further.
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19 SOCIAL IMPACT ASSESSMENT
19.1 Potential Environmental Effects
A Social Impact Assessment report was prepared by Taylor Baines (Taylor Baines, May 2013) on the
social and socio-economic effects associated with the proposed Scheme.
Key land use changes anticipated with irrigation are:
• Dairying and its associated dairy support
• Intensified horticultural operations
• Irrigated arable farming
• Some irrigated sheep and beef farming.
The assessment found that, based on analysis of the Scheme area and comparative areas of New
Zealand, this level of land-use change will lead to a series of social changes driven by changes in land
use, new farmers moving into the area with new or different approaches to debt and farming
practices, and higher levels of employment with more intensive farming practices. While these
changes will lead in turn to strengthening of local populations and communities through the
employment created (on and off farm) and additional business activity, including in the towns of
Waipukurau and Waipawa, potential social issues could arise with land use change around the
integration of newcomers, loss of sense of place and possible values conflicts. With appropriate
strategies in place to manage change, however, the proposed scheme should result in a significant
net beneficial social effect for the people and communities of the district.
19.2 Assessments Undertaken
The scope of the assessment was directed at the potential social effects of the scheme associated
with:
• Changes in farming practices
• Changes in land ownership
• Demographic changes (numbers and composition of the population)
• Strengthening rural communities (education, health, commerce, clubs, etc)
• Value conflicts associated with new / intensified land uses versus traditional dryland farming
practices
• Wider regional socio-economic effects including construction effects.
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A multi-method approach was used with the main phases being scoping of effects and profile of the
assessment area, assessment of effects, feedback and validation of findings, and reporting. The main
sources of information were:
• Analysis of data about the affected communities and social trends from census and other
secondary data sources
• Use of a scenario of potential land use change and projection of likely changes in farm
ownership, employment and populations
• Analysis of social infrastructure and likely changes in communities resulting from changes in
numbers and characteristics of farmers, farm workers and their families
• Information from meetings with stakeholders and key-informant interviews to assist with
understanding of social issues and trends and likely changes with irrigation.
19.3 Results of Assessment
There are approximately 470 farms greater than 10 hectares in irrigation zones A to D and M. The
report concluded that increased areas of irrigation and associated changes in land use on these
farms will lead to the following effects:
• A reduced average age of farmers and new families coming into the area
• Some of the new farm workers are likely to live in the villages and main townships and some
seasonal workers in on-farm accommodation camps
• A turnaround from negligible growth in population evident in the district over recent years –
in both rural areas and the main towns
• A flow on effect of growth in numbers employed and population for any new processing
plant associated with new or increased farm outputs
• A change in the composition of the population, especially of the rural areas, with younger
families and children and consequent rises in school rolls
• Increased turnover of population and more overseas workers, with more ethnic diversity and
a need to provide social support to new comers
• Increased participation in sport and recreation and community activities and greater demand
for social services, including health services, although with the exception of health there are
facilities and capacity to meet new demand.
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Other potential effects identified included:
• New and increased health and safety risks around new waterways, increased traffic on rural
roads and on farm with intensified activities. There may be a perception of risk around dam
failure
• Consequences of residual bio-physical effects on local people and communities from
construction activities, alleviated by suitable mitigation measures and management plans
• Changes in recreational and cultural values as identified in the recreation and cultural
assessments with potential for community tensions and conflict in the shift to an inherently
adversarial planning process.
19.4 Suggested Approach for Effects Identified
Experience with irrigation projects demonstrates the importance of a proactive approach to
managing social and economic change to achieve desired social-economic outcomes. The net social-
economic benefit of the scheme will depend on active management of change by the councils and
key stakeholders, along with communication and consultation with the affected communities.
Taylor Baines concluded that active involvement of the two councils along with the stakeholder
group provides an opportunity to develop a change management strategy around the following
initiatives:
• Develop a social impact management plan for the construction phase as part of the front-
end engineering design of the headworks in order to maximise local employment benefits
from construction and avoid adverse effects of an incoming workforce
• Develop a coordinated employment strategy with agencies and training providers for future
land uses and off-farm opportunities including training and skills development, with an
emphasis on local placement, including working closely with Maori
• Prepare a business development strategy working with regional and district business
development agencies and sector groups
• Build on community, youth and sports and recreation development in the district to enhance
community benefits from incoming population
• Establish a programme to assist the integration of newcomers into the community, including
migrants from outside the district and overseas workers
• Establish a programme of technology transfer for the uptake of the latest land, water and
nutrient management practices to enhance social, economic and environmental outcomes.
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• Develop a community strategy to identify and encourage retention of features that reinforce
sense of place as land uses change.
• Undertake a comprehensive communications strategy for the scheme through the
consenting and construction phases, with regular communications through multiple media,
to support participation of interested and affected parties through the rest of the planning
and design process.
HBRIC Ltd accepts the general tenor of these recommendations but does not consider that they are
suitable to incorporate as consent conditions within Part D- Proposed Conditions of this application.
Because they rely upon the enthusiasm and participation of a number of stakeholders including (but
not necessarily limited to) Business Hawke’s Bay, CHBDC, HDC and mana whenua, HBRIC Ltd
considers that a more appropriate approach is to develop a Memorandum of Understanding with
these stakeholders and discuss and evolve a suitable terms of reference in consultation with them. It
proposes to implement that approach to Taylor Baines’ recommendations.
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20 RECREATION ASSESSMENT
20.1 Potential Environmental Effects
A report prepared by OPUS (OPUS, May 2013a) assesses the recreational values and effects of the
Scheme. OPUS considers that potential recreation effects of the proposed Scheme include the
following:
Recreation Zone 1 - (upstream of the dam head)
• Effects on access to the Ruahine Forest Park for a range of recreation activities including
tramping/ hiking, hunting, mountain biking, kayaking and fishing
• Effects on the activity of fishing, four wheel driving and kayaking in the dam footprint. The
opportunity to undertake these activities in ‘recreation zone 1’ will be affected
• Effects on day visits and the activities associated with scouts/ Wakarara Camp at the
Wakarara Road End and associated heritage and natural amenity areas. The Wakarara Road
End will be affected
• The activity of camping will be affected. The private camping ground at Wakarara Road End
is located within the dam footprint.
Recreation Zone 2 - (between the dam head and the upstream water intake)
• There will be no effects on existing access to the Makaroro River and Waipawa River
• Monthly mean flows would be generally more consistent during the year. There would be
greater flow (compared with current flows) in the summer and lower flows (compared with
current flows) in the winter. Average flows during the irrigation season (October to April)
would be considerably higher. Although the activities of fishing, swimming and kayaking will
not be lost, the nature of the activity in recreation zone 2 will change.
Zone M – (forms part of the wider distribution network)
• The recreation activities that occur at Walker Road end are unlikely to be affected by the
intake structure proposed in this area
• Currently the Papanui Stream has low amenity values characterised by low flows and
weed growth. As part of the proposal to utilise the stream for the conveyance of
irrigation water through Zone M, it is proposed to improve the in-stream ecology,
general amenity through a Papanui Stream Rehabilitation Plan as set out in the Proposed
Resource Consent Conditions. This rehabilitation may ‘provide recreation opportunities,
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such as developing a walking/cycling path, linking the settlements of Otane and
Waipawa at the edge of the new riparian margins along a portion of the Papanui Stream,
subject to engagement and approval by with landowners’, thus creating a positive
environmental effect. Our conclusion is that Zone M (Papanui Stream Section) has the
potential to have a positive recreational effect through the provision of cycling
opportunities suitable for recreational cyclists of all ages as well as additional walking
opportunities.
Effects during Construction
• Effects on access to all current recreation activities during construction
• Effects on the activities of kayaking, fishing, four-wheel driving, day picnicking and swimming
during construction.
20.2 Assessments Undertaken
HBRIC Ltd commissioned Opus to prepare a Recreation Assessment (April 2012) which addresses the
following:
• Identify and characterise the range of recreational activities undertaken in the Scheme area.
Determine the context of these opportunities on the basis of the range and availability of
existing outdoor recreational opportunities within Hawke’s Bay and surrounding regions as
well as their proximity to people living in Hawke’s Bay
• Assess the effects of the Scheme on the identified recreational activities being undertaken in
the Scheme area
• Identify and characterise any new recreational opportunities that may be created by the
Scheme, and their potential benefits (in the context of the availability of existing outdoor
recreational opportunities available to Hawke’s Bay residents)
• Identify and report on any available and appropriate means to avoid, remedy or mitigate
adverse effects on current recreational use of the Scheme area.
The Recreation Assessment was undertaken between the months of December 2011 and February
2012 as part of the feasibility stage of the Scheme. It entailed observation from two site visits;
consultation with key stakeholders and recreational groups; and research of relevant literature to
develop a sound understanding of the Scheme area and proposal (as it then was) and associated
recreation activities currently undertaken. Findings from other dam developments were also
reviewed particularly where recreation has been considered. This assisted in developing an overall
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impression of the activities affected, possible mitigation for the effects identified and possible
opportunities for a scheme of this nature. A further site visit was undertaken in March 2013 to
assess the changes from the Feasibility Design to the Application Design, which for the purposes of
this report focus primarily on the inclusion of Zone M to the Scheme.
20.3 Results of Assessment
Overall the main effect on recreation will be loss of access to recreation activities in the wider area.
It is recommended that alternative access to these activities be provided for in the long term. This
has been adopted in the Project Description (Tonkin & Taylor, May 2013a) by HBRIC Ltd including a
commitment to alternative access around the top end of the reservoir.
The other key conclusion of this report is in relation to the opportunity the completed dam and
reservoir will have for recreation activities. Flat water is sought after in Hawke’s Bay for rowing and
motor boat activities, and it is acknowledged that there is potential for these and a range of other
recreational activities such as fishing, swimming and lakeside activities to be provided for at the
reservoir. Proposed mitigation acknowledges the provision of these activities is a desired outcome
and the report recommends that work be undertaken with user groups to better understand their
needs and the ability of the dam to accommodate these.
Issues such as water plumage; de-vegetation (or lack of) and how this is managed; and treatment of
the ‘dead zone’ around the dam periphery will potentially place constraints on the dam for
recreational use.
20.4 Suggested Approach for Effects Identified
A workshop on a potential integrated mitigation and offset programme associated with the physical
effects of the Scheme on the environment was held on 6 March 2012. This was attended by
representatives from the Department of Conservation (DoC) and Iwi along with the authors of the
recreation, landscape, archaeology and terrestrial ecology reports. The recommendations
contained in the recreation report were discussed at the workshop.
Following further engagement with landowners and other stakeholders over the period since that
meeting to discuss implementation of these recommendations, HBRIC Ltd has completed a separate
report entitled "Ruataniwha Water Storage Scheme – Proposed Integrated Mitigation and Offset
Approach" (HBRIC, May 2013f). This explains the commitments being made to address or offset any
adverse effects of the Scheme including on current recreation activities, particularly in the reservoir
area, and to support or promote new recreational opportunities created by the Scheme.
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The suggested approach for effects identified for each recreation activity assessed in this report
applies these commitments as recorded in HBRIC (May 2013f). Proposed conditions of consent
incorporate these commitments including the requirement to implement the Integrated Mitigation
and Offset Approach and through the Reservoir Filling and Edge Rehabilitation Plan to be
progressively implemented upon commencement of construction of the Scheme.
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21 ROAD INFRASTRUCTURE AND TRAFFIC
A Road Infrastructure and Traffic Assessment report prepared by OPUS (OPUS, May 2013b) assesses
the impact that the Scheme will have on existing road infrastructure and provides recommendations
on improvements where required, along with appropriate monitoring, inspection and response
measures over the course of the project (construction phase in particular).
21.1 Potential Environmental Effects
Potential Scheme effects considered as part of this report are:
• Suitability of the roading network affected by the Scheme, in terms of adequate pavement
strength and appropriate geometric alignment
• Structural capacity of existing bridges affected by the Scheme
21.2 Assessments Undertaken
The following assessments were undertaken:
• Magnitude of construction traffic
• Roads affected by construction traffic
• Bridge infrastructure affected by construction traffic
• Traffic loading requirements of the construction traffic
• Road pavements and surfacing affected by construction traffic
• Suitability of existing road alignments.
21.3 Results of Assessment
21.3.1 Bridge Infrastructure
All the bridges affected by the construction traffic are currently assumed to withstand a Class I type
loading, as none have any restriction on their live load carrying capacity. However, local CHB bridges
will see a large increase in their current traffic volume which may affect their load carrying capacity,
and so ‘before, during and after’ inspections for the construction period are proposed along with
appropriate remedial response (refer below)36. It is considered that the effect of the construction
traffic on the SH bridges will be minimal.
36 The proposed conditions in Part D expand the scope of the proposed inspections to include culverts as well as bridges.
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21.3.2 Road Pavement and Surfacing
Delivery of initial plant to site and dam construction traffic are likely to follow similar routes. Any
overweight loads are likely to impact on the road surfacing in vulnerable areas, such as curves and
intersections. In particular, sections of SH50 and Wakarara Road have curvilinear alignment which
may be impacted by construction traffic. The surfacing on Wakarara Road are also all single coat
seals which will be more susceptible to shear related distress or binder pickup on the vehicle tyres,
particularly at surface temperatures above 40°C.
A further factor to consider with overweight and over dimension vehicles is any pavement and
surfacing construction works being undertaken during the period of transportation. If this takes
place during the period from October to March, there will be pavement rehabilitation construction
and resurfacing completed on isolated areas along the construction traffic routes which will be
impacted by construction traffic.
For State Highways, based on the preliminary analysis there is unlikely to be any significant impact
on the existing pavement from the additional construction traffic on this route.
Local Authority roads, in particular sections of Wakarara Road may be impacted due to the
proportional increase in heavy vehicle loadings (double existing traffic on some lengths). The
increased loading requires an increase in design pavement depth. However, for the majority of the
existing road, pavement depth and age data could not be obtained to verify actual improvement
requirements.
21.3.3 Road Alignment
A desktop assessment has identified two possible sites on Wakarara Road which may warrant further
investigation to check their suitability for an increased number of heavy vehicles during the
construction period. These are the curve immediately west of Hardy Road and curves at Pendle Hill
Road.
21.3.4 New Access Roads
The main dam access road is likely to require a granular pavement to a depth of up to 300mm and a
minimum width of 5.0m.
An existing forestry access road and a farm access track will become inundated with water from the
reservoir once the dam is completed. Potential alignments of alternate accesses have been
identified.
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21.3.5 Beach Nourishment Operation
Once the dam is operational annual beach nourishment of 3,400 m3 is required to mitigate the
downstream effects of the dam. The location of this is shown in Figure 3 of the report . This would
result in approximately 280 return trips by truck and trailer vehicle (assuming 12m3 capacity). This
annual operation will be carried out around October / November after the winter storms. This
would represent an additional 22-28% increase in daily HCVs for a 10 day operation.
21.4 Suggested Approach for Effects Identified
Bridge Infrastructure
Due to the increase in the volume of traffic the Central Hawke’s Bay bridges will experience during
the construction stage of the Scheme, it is recommended the affected structures are evaluated in
accordance with the NZTA Bridge Manual Section 6 and their load carrying capacity confirmed. The
evaluation will need to take into account the current condition of the structures as some defects (i.e.
deck cracking) may decrease their load carrying capacity.
In order to assess any changes during the construction period in the condition of both local Central
Hawke’s Bay and State Highway bridges, it is recommended a regime of inspections is established.
It has been assumed most of the construction traffic will be Class I loading and it is recommended
the traffic is limited to this in particular over the CHB Bridge infrastructure. Nevertheless, if an
overweight load (indivisible) needs to be taken into the construction site an Overweight Application
Process could be completed as detailed in the OPUS report.
Alternatively, the construction route could also be assessed as a HPMV route if it is considered there
will be more frequent or regular demand to carry heavier than Class I type loading. Both of these
processes will entail carrying out bridge evaluations specific to the desired traffic configuration and
weight of vehicles. As a consequence, bridge strengthening/replacements may be required to
achieve the higher load carrying requirements.
Road Pavement and Surfacing
In order to minimise the likely hood of damage to surfacing from overweight vehicles associated with
initial plant delivery, the following conditions are recommended for inclusion within the proposed
Construction Traffic Management Plan (CTMP):
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• The maximum surface temperature that any section of the pavement on the construction
traffic route should be trafficked is 40°C. This maximum could be raised to 45°C if experience
shows that no damage occurs at temperatures close to 40°C.
• No overweight loads should be transported over any seal that is less than one week (7days)
old.
Further, it is recommended that no transportation of overweight/over dimension loads should take
place during and for a week long period following any pavement rehabilitation construction. This
condition will allow pavements to be constructed without interruption and will allow the cement
stabilised pavements to “set up” prior to heavy loading.
It is recommended that vulnerable areas of the routes to be used by construction traffic (as
identified in the OPUS report) be regularly (e.g. 3-monthly) monitored throughout the construction
period. This should be completed by experienced surfacing practitioners (e.g. network consultants).
Where any failures of the surfacing, including reduced skid resistance, are observed the areas should
be resurfaced.
Monitoring of older sections of pavement on both State Highways and Local Authority roads should
be carried out throughout the construction period and maintenance completed as required to
ensure the road continues to meet the Levels of Service set by road controlling authorities. The
monitoring could be carried out by network maintenance contractors during their normal monthly
inspections and any maintenance issues that appear to be outside normal expected maintenance
requirements reported to the dam construction project management team.
It is recommended that where the existing pavement depth and age is unknown this is verified
through on site testing to establish its current capacity. This would include using more detailed
project level FWD testing and/or destructive test pitting and subgrade scala penetrometer testing.
From this information on the current subgrade strength, pavement depth, materials and an
indication of pavement age can be determined. If areas of the pavement prove to be inadequate,
pavement rehabilitation works should be undertaken, such as an overlay of granular basecourse or
stabilisation of the existing pavement.
At the end of construction period all pavement lengths should be assessed by experienced
practitioners using appropriate visual inspection and condition data to determine any significant
deterioration beyond normal expected deterioration based on modelling and forward works
programmes. Those areas deemed to have deteriorated to an unacceptable level would need to be
rehabilitated.
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Road Alignment
On site topographical survey of identified potential problem areas should be completed and actual
construction traffic configurations sourced, particularly for over-dimension vehicles. From this
information a more detailed swept path analysis can then be undertaken to determine actual
realignment requirements.
New Access Roads
In order to reduce dust along the main dam access route, the report recommends that it be
chipsealed as this route will carry the majority of construction traffic.
The existing subgrade along new access routes should be tested using scala penetrometer testing to
verify actual granular pavement depths required.
Replacement forestry and farm access roads will need to be constructed similar to existing in
consultation with the landowners’ requirements.
Beach Nourishment Operation
The beach nourishment operation will likely represent a 28-28% increase in HCV volumes for a 10
day operation. It is recommended the local residents be informed beforehand when this annual
operation takes place.
The above recommendations are implemented through the proposed conditions of consent.
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22 NOISE EFFECTS
The RWSS comprises very significant earthworks and construction activity in and around the
Makaroro River. Significant amounts of noise will be produced over approximately a four and half
year construction timeframe. A report prepared by Marshall Day (Marshall Day, May 2013) considers
the noise sources, reviews the standards and assessment methods for evaluating noise effects,
presents predicted noise levels from the activity, and recommends mitigations to avoid, remedy or
mitigate noise effects.
22.1 Potential Environmental Effects
The noise effects which are expected to arise from the proposed water storage scheme are almost
entirely related to construction activities. These include construction of access roads, excavation and
transport of aggregate, placement of aggregate and spoil, blasting, concrete batching and
placement, and site reinstatement. This will occur in the vicinity of the proposed dam site and to a
much lesser extent near the water intake site and along the water distribution network. These sites
are generally at large distances from dwellings.
The noise effects from the operation of the water storage scheme will be very limited, and will
generally consist of a modification of natural noises rather than introduction of man-made noise.
The Beach Nourishment Scheme has potential noise effects associated with the transport and
deposition of sediment.
22.2 Assessment Undertaken
This assessment of noise effects has been made by comparing predicted noise levels from
construction activities to the applicable noise standards, including district plan noise limits and the
Construction Noise standard (NZS6803:1999).
Noise predictions have been made on the basis of typical construction machinery sound power
levels, with geometry and duration as described in the Project Description document (Tonkin &
Taylor 2013a). Noise is predicted using the ISO9613-2 Industrial Noise Model, implemented in
SoundPLAN software.
22.3 Results of Assessment
Construction noise levels are predicted to comply with daytime construction noise limits in
NZS6803:1999 at all dwellings and night-time construction limits at most dwellings.
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The noise effects at all dwellings are considered to be reasonable provided that adequate
consideration of night-time noise mitigation at near dwellings Rec 6, 7 and 937 is taken into account
during certain specific periods of construction. This may require limiting activities at night-time, or
providing some other means of mitigation to the residents of those dwellings.
The noise levels in the working rural environment are considered to be reasonable, and are not
predicted to have adverse effects.
The noise level and character of the on-going operation of the water storage scheme are consistent
with the expectations of rural land near a water course, and no adverse noise effects are predicted.
Noise effects from the beach nourishment scheme are predicted to be minor or less than minor
except along the residential portion of Haumoana Road where noise effects from truck traffic may be
significant for a one week period each year. We would consider this noise effect reasonable given its
short duration, and relative to noise levels provided for in NZS6803:1999.
22.4 Suggested Approach for Effects Identified
The report recommendation to address construction noise issues in a construction noise
management plan has been implemented by the applicant in the Construction Environmental
Management Plan (CEMP). The report concludes that the CEMP will ensure that construction
activities are carried out in a manner which avoids unreasonable noise emissions, and which ensures
that adverse noise effects are appropriately mitigated at the three dwellings identified as well as at
any noise sensitive locations which are found to be affected near the headrace construction. The
CEMP will also provide a means for good communication with the community and a pathway for
feedback to the project team regarding noise concerns.
With this CEMP, adverse noise effects will be avoided or appropriately mitigated.
37 As described more fully in Marshall Day (May 2013)
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23 REGIONAL ECONOMICS
23.1 Potential Effects
The assessment of Regional Economic Effects and net national benefits is presented in a report
prepared by Butcher Partners Limited (Butcher, May 2013). The report is based on the Project
Description prepared by Tonkin & Taylor38. It also applies information supplied by Macfarlane Rural
Business Ltd (MRBL)39 as to ‘before and after’ Scheme land irrigation use scenarios, along with on
farm conversion costs and returns.
Applying the post Scheme land use irrigation scenario adopted by MRBL, the proposed Scheme will
irrigate 19,000 Ha of dry land40 with potential to provide increased reliability of irrigation on a
further 6,000 Ha of currently irrigated land. The Scheme is estimated by Tonkin & Taylor to cost
$24641 million for an in-river dam, a headrace which is a mix of piped and open channel, and then
piped distribution beyond the headrace, although farms will generally not get water at sufficient
pressure for irrigating.
On-farm investment will depend on the land uses on the newly irrigated land, but base case
estimates42 by MRBL are that the farmer investment will cost $356 million, including $247 million for
physical investment on-farm, $16 million for livestock, and $93 million for dairy company shares and
working capital.
23.2 Assessments Undertaken
The scope of this assessment was the net national benefit from a commercial perspective only, and
the net regional economic impacts in terms of regional GDP, employment and household income.
These arose from:
• Change in land use on irrigated land and changes in farming practices
• Industry support effects arising from the expansion of output in those industries which
directly or indirectly provide supporting goods and services to agriculture
• Changes in output of processing industries including for meat, milk, grapes and vegetables
38 Tonkin & Taylor (May 2103a) 39 Macfarlane Rural Business -Macfarlane September 2012 40 This is a conservative assumption to ensure the economic benefits are not overstated, and assumes 6,000 Ha of Scheme
irrigation capacity is used to irrigate land already irrigated by less reliable surface water and ground water takes, rather than being applied to irrigate additional land.
41 Includes $7 million of mitigation costs over the Scheme lifetime. 42 Adjusted to remove increases in raw land value, and allowing for some existing plant being redundant or unsuited to new
farming practices.
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• Effects on Napier Port.
The benefits and impacts are based on an analysis of likely irrigated areas, irrigated land use mix, and
farm financial performance as estimated by MRBL.
There is considerable uncertainty as to the exact mix of land uses on future irrigated land, the level
of processing of production from the irrigated farms, and the proportion of processing which will
take place in the region. The figures given here are realistic assessments of what is likely to occur,
but actual outcome could be higher or lower than this.
The cost benefit analysis in the report ignores any environmental effects which arise from the land
use changes. The cost benefit analysis also ignores any benefits arising purely from increased
employment opportunities, or from increased value added in industries other than farming. This is a
conservative position, but reflects the possibility that in an efficient economy the capital and labour
would otherwise be used elsewhere in the economy and the expansion of irrigation does not actually
provide any additional employment.
The analysis also ignores any benefits arising from additional irrigation water that will on occasion be
available43. Nor has any assessment been made of the potential for using some water to supplement
water available to other downstream users. While this water may have greater value in use
downstream, its use will reduce either irrigable area or reliability in the existing production land
area, the additional value has been neither estimated nor proved.
The economic impact analysis shows the potential scale of impacts, provided there are spare
resources of labour and capital available. The Butcher (May 2013) study did not include a regional
general equilibrium analysis.
23.3 Results of Assessment
23.3.1 Economic Benefits
The Net Present Value of the Scheme is estimated to be $7 million at an 8% discount rate. In broad
terms this benefit is equivalent to the Scheme participants44receiving a 35 year stream of benefits of
$0.6 million / year (after all the costs of additional on-farm and off-farm capital have been met).
43 See Tonkin & Taylor (May 2013) Section 3.2.2.6 which refers to secondary irrigation water of up to 28 million m3 per
year. Given the uncertainty surrounding the availability and reliability of this water, and its potential use for purposes other than agriculture, no assessment has been made of the benefits or regional impacts of this water.
44 Farmers and the irrigation supplier.
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Reducing the discount rate to 5 %45 increases the NPV to $225 million, equivalent to $14 million per
year in net benefits to farmers and the irrigation supplier.
The base line 35 year Scheme life corresponds to the proposed water right term and 8 % is the
recommended Treasury discount rate. Using different assumptions of a 70 year Scheme life and a
5% discount rate, which arguably is more consistent with farmers’ investment decisions elsewhere
and with a societal concern about long term impacts and the likely minimum life of the irrigation
infrastructure, the benefit has a NPV of $408 million, which is equivalent to $21 million per year. It is
our view that from a community and farmer perspective these latter figures are more relevant. This
benefit can be thought of as a “super profit”; a return above what the resources used in this Scheme
would normally earn elsewhere and accrues to farmers and the irrigation supplier.
The above assessments of benefit follow a standard CBA assumption that apart from this “super
profit”, there is no net benefit from the Scheme. The extra production both on and off-farm requires
the use of resources (land, labour and capital) which could otherwise have been used elsewhere in
the economy to achieve the same community economic and social impacts and benefits as they will
in these projects. Hence there is no particular additional benefit from investing in the Scheme.
This assumption is not accepted by many in the community who are of the view that this Scheme will
provide more jobs and income than would occur in the absence of the Scheme, and that accordingly
the community is better off and there is a net benefit. The magnitude of the benefit will likely be
debated with opinions ranging upwards from zero.
Against these benefits need to be weighed up any wider community social, recreational and
environmental outcomes associated with the change in water use and river state.
Table 23.3.1a - Net Present Value of Ruataniwha Scheme
Values at full development Financial Value NPV 8 % over 35 years ($m)
NPV 5 % over 35 years
Water Storage Capex Farm Investment Capex Electricity Generation Scheme Operating Costs Revenue from Water Charges* Increased Farm Profit**
- $246 m
- $356 m $1.9 m / yr - $2.5m / yr $19 m / yr $65 m / yr
- 203
- 229 21 -29 136 308
-217
-268 30 -40 218 501
Net Benefit + 7 +225
* Assumes charges of $0.20 / m3 45 There are strong arguments in favour of a lower discount rate, of the order of 3 – 5%, This reflects a “Social Rate of Time
Preference”, and is also consistent with observable farmer decisions regarding land purchase prices and other on-farm investments. See NZIER Insight no. 32/2011 for a discussion of the issues.
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** After adding back water charges, which are assumed to be sufficient to cover capital and operating costs.
The results assume all water will be taken up within 8 years of the Scheme becoming operative, and
also rely on the farm budgets presented by MRBL. The results also assume that the Scheme will
provide water for only the 35 years covered by the water consent, and hence implicitly assume that
infrastructure at this point has no residual value. Changing this restrictive assumption to a 70 year or
100 year lifetime of the Scheme increases the Scheme NPV as is shown in Table 23.3.1b below. The
net financial benefit of the Scheme at a 5 % discount rate and a 70 year life is $408 million, which is
equivalent to $21 million per year.
Table 23.3.1b Net Present Value of Scheme ($m) under varying assumptions
Scheme Life 8 % discount rate 5 % discount rate NPV
($m)
Equivalent Annual Value
($m/yr)
NPV
($m)
Equivalent Annual Value
($m/yr)
35 years 70 years 100 years
7
54 57
0.6
4.5 4.6
225
408 439
14
21 22
The commercial benefits arising from expanding the area in orchards and vineyards, as measured by
the NPV, are negative at a discount rate of 8 %. This is consistent with the MRBL report showing
marginal accounting rates of return of 9.5 % for orchards and 7.5 % for vineyards46. While these
rates roughly straddle the discount rate, implying a close to zero NPV for these activities, the
accounting rate of return does not reflect the time lag between investment and full production,
which is four years for vineyards and six years for orchard. Hence the IRR for orchards and vineyards
is less than the discount rate and the NPV is negative.
There is a clear net commercial benefit to farmers and the irrigation supplier from irrigation over and
above the opportunity cost of capital and labour employed in increased production, and this benefit
is what the Scheme NPV measures. The Net Present Value calculation ignores any net recreational,
environmental and community costs and benefits of irrigation. The recreational and environmental
values will be discussed by others with expertise in these areas, but the impacts on regional
employment and income are outlined in this report.
The report notes an expectation that people in other sectors who experience an increase in
economic activity will also perceive themselves to be receiving a benefit. The formal cost benefit
46 MRBL 2012, p44. Assuming conversion from finishing farms
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analysis framework does not recognise this latter benefit because of the framework’s restrictive
assumptions regarding price equalling opportunity cost in these other sectors47. It is for this reason
that we show in the following sections the increase in employment, regional GDP and regional
household income. Decision makers can take these impacts into consideration when deciding
whether the Scheme has larger benefits than costs when viewed from the widest societal
perspective.
23.3.2 Economic Impacts
The economic impacts arising from the Scheme have two components. The first is the impact of
construction on and off-farm. This is a one-off impact, and for this reason impacts are expressed as
$million (rather than $million per year) and job-years (as opposed to on-going jobs). The second
component of economic impact is the on-going effect of increased farm production. This generates
impacts including:
• on-farm
• in all the industries that support farming production and farm household spending (e.g.
agricultural contractors, stock and station agents, rural transport, shops and service
providers)
• In processing industries such as meat, dairy and vegetable processing, and in all the
industries that support the processing industries and the household spending that flows
from them.
Economic impacts are generally reported in terms of changes to output (sales), value added48
(sometimes referred to as regional income or regional GDP), household income (which is a
component of value added) and employment. The impacts are split up into the direct effects, which
in this case are the direct changes in output, employment and income on-farm, and the multiplier
effects, sometimes referred to as the indirect and induced effects, or the industry-support effects.
One-Off Construction Impacts
The investment of $602 million leads to economic impacts during construction including an increase
in regional value added of $350 million, including household income of $230 million, and an
additional 4,000 job-years of work. This economic impact will be focussed on the first four years,
when all the dam construction and the first 56 per cent of pastoral on-farm investment are assumed
47 In simple terms, formal cost benefit analysis assumes that unless there is reason to assume otherwise, price equals
opportunity cost, which is the benefit foregone in the next best possible use. 48 In accounting terms this is equivalent to EBITDA.
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to take place. The balance will be spread over the remaining eight years of the investment
programme until land development is completed.
Table 23.3.2a Regional Economic Impacts of Ruataniwha Scheme – Construction-related only (One-off effects spread over 12 years)
Output
($m) Jobs
(job-years) Value Added
($m ) H/hold Income
($m) Direct Impacts 602 na na na
Total Impacts 1,100 4,000 350 230
On-Going Impacts Arising from Increased Farm Production
The Scheme will increase farm-gate output by $160 million per year. This increase will be
accompanied by an increase in direct value added49on farm of $70 million per year, including $25
million per year of earned50 household income. There will be an increase of 630 jobs on farm, with
500 of those occurring in vineyards and orchards (see upper section of Table 23.3.2b).
Multiplier effects arise as a result of the expansion of economic activity in supporting industries. The
combination of direct impacts on farm and multiplier51effects in the farm-support industries gives a
total increase in regional value added of $127 million per year, of which earned household income
will be $52 million per year. The additional 530 jobs created off-farm give a total increase of 1,160
jobs in the region (see lower section of Table 23.3.2b).
Table 23.3.2b Regional Economic Impacts of Ruataniwha Scheme – Farm and Farm-Support Only at Full Development
Increase Output ($m / yr)
Jobs (FTEs)
Value Added ($m / yr)
Household Income ($m/yr)
Pastoral and arable farming direct Orchards and Vineyards (or similar) Sub-Total – Farming
107
53 160
130
500 630
40
30 70
8
17 25
Farm support effects (multiplier effects) 120 530 56 27
Total Farming and Farm Support 280 1,160 127 52
About 55 % of these farm and farm-support regional employment and value added impacts occur on
farm. There are also significant effects on agricultural contracting, wholesale and retail trade,
transport and communications, and services (including local authorities who get an estimated $2.4
million per year extra in rates income). 49 Value added is the return to labour and capital. It is the equivalent concept to Gross Domestic Product. In accounting
terms it can be seen as EBITDA + wages & salaries, or as gross output less purchases of inputs (other than capital and labour).
50 Wages and salaries, plus self-employed income. Excludes any dividends from increased profits 51 Sometimes called indirect and induced effects.
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About 80% of direct on-farm employment, 40% of direct value added and 70% of direct household
income arises from conversion to either viticulture or orchards. If there is no expansion of either of
these activities52, total value added in the region would increase by only $77 million per year (rather
than $127 million) and total employment would increase by only 510 jobs (rather than 1,160 jobs).
As described earlier, investment in these activities is by no means certain, with a commercial return
(IRR basis) being less than 8 %.
On-going Impacts Arising from Increased Processing
Additional processing of vegetables and grapes, slightly offset by a decline in processing of meat,
could significantly increase the regional economic impacts. We estimate that if all the extra
processing of these items was done within the region, then there could be additional economic
impacts of 980 jobs and $93 million/ year of value added, including $53 million per year of household
income. There is no significant dairy factory in the region, but if one was developed and half the
additional dairy production was processed within the region, then a further 110 jobs could be
created along with value added of $14 million per year, including $7 million per year of household
income (see Summary Table 2, lower section). Butcher (May 2013) cautions that there is enormous
uncertainty associated with these numbers because of the uncertainty as to the mix of irrigated land
uses, and hence the mix of product available for processing, and the location of any resultant change
in processing activities (see lower section of Table 23.3.2c).
As is shown in Table 23.3.2c, the Scheme and the associated increase in farm production following
full implementation, with all processing and related supporting industry activity factored in, could
increase total regional GDP by $235 million per year or 4 %53, including an additional $110 million per
year in regional household income. The Scheme could increase total regional employment by 2,250
on-going jobs, or 3.5 % of current Hawke’s Bay employment.
52 Assuming that the land instead converted to mixed arable farming 53 Latest available data for 2006-07
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Table 23.3.2c On-going Regional Economic Impacts of Additional Agricultural Production Arising from the Ruataniwha Scheme (at full development)
Output
($m / yr) Jobs
(FTEs) Value
Added ($m / yr)
Household Income ($m/yr)
Farming and farm support 280 1,160 127 52
Processing and processing support
(high uncertainty)
340 1,090 108 58
Potential Total Impacts per year 620 2,250 235 110
Potential NPV of impacts (8 % over 35 years)
(5 % over 70 years)
2,500
4,700
17,800
34,300
1,800
3,500
910
1,700
The impacts reported here should be seen as likely upper limits to the net impacts on the
community5455. The estimates are based on an implicit assumption that there will be labour
available to take up these jobs, and that the people taking them up will be either unemployed or out
of the labour force in the absence of the irrigation, or will be migrants into the region from
elsewhere. To the extent that the jobs are filled by people leaving existing jobs in the region and
those jobs are not filled, the impacts will be lower than is estimated here.
Effects on the Port56
The additional product could lead to up to 9,000 additional full containers per year being shipped
through Port Napier, which could increase port earnings by perhaps $1.3 million per year. The
number of additional containers is significantly affected by the level of processing taking place in the
region, and by shippers’ decisions as to the best port to use given the schedules of the shipping lines
at the time.
Farmer Affordability
MRBL believes that farmers look at accounting rates of return rather than more formal NPVs or IRRs.
The available data suggests that conversion will be affordable from the farmers’ perspective. The
MRBL estimate of the accounting rates of return on marginal farm investment are 10 - 15 % for
54 For the assumed land uses. Different land use mixes will give different results. 55 It has been assumed that owners of 6,000 Ha irrigated from current ground-water permits will surrender their water
rights and take water from the Scheme. Hence the economic impacts are based on an additional 19,000 Ha irrigated. If these users do not transfer, then there will be a net increase of 25,000 Ha irrigated, and the benefits and economic impacts will be correspondingly greater. It is understood that the analysis of environment effects associated with such things as nitrate leaching is based on the assumption that there is a net increase of 25,000 Ha irrigated. Hence the assumptions differ, and either the economic impacts will be greater than is assessed here, or the negative environmental effects will be less than has been assessed.
56 Economic impacts associated with increased port activity are included in the processing effects.
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dairying, 6 % for finishing, 4 % for mixed arable, 30 % for intensive arable with crops for processing,
and 65 % for mixed livestock and dairy support.
The benefit on farms will be derived from a number of sources.
On the irrigated area:
• An increase in production associated with irrigation of existing systems
• A change in systems to higher intensity land uses such as dairying and cropping which are
possible with more reliable irrigation
• Reduced farming risk, which increases returns by enabling famers to move towards more
risk-neutral behaviour, which generally has a higher average return than does a risk-averse
management style.
On associated dry land:
• Ability to manage associated dryland areas better, given the increased flexibility which
irrigation usually generates.
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24 ARCHAEOLOGICAL ASSESSMENT
24.1 Potential Environmental Effects
A report prepared by Clough and Associates (Clough and Associates, May 2013) considers the
historical heritage and archaeological impact of the Scheme. The report notes that the Scheme has
some potential to destroy, damage or modify archaeological sites. This potentially applies to:
• Previously unrecorded but visible archaeological sites
• As yet unknown archaeological sites that might be exposed by earthworks.
24.2 Assessment Undertaken
An archaeological survey and assessment of the areas affected by the RWSS (the reservoir, dam,
headrace corridor and reticulation network) was undertaken by Clough & Associates. The
assessment involved:
• A search of the NZ Archaeological Association’s site record database (ArchSite) and the
Central Hawke’s Bay District Plan schedules for information on any recorded or scheduled
archaeological or other historic heritage sites
• A search of early Survey Office (SO) Plans and Deposited Plans (DP) held by Land Information
New Zealand (LINZ) for information on former land use
• A brief review of literature and archaeological reports relevant to the area
• Meetings with Dr Benita Wakefield and staff of Te Taiwhenua ō Tamatea, and Pat Parsons
regarding the cultural and historic heritage aspects of the RWSS. Historical background
information provided by Pat Parsons has been included in this report
• An initial visual inspection of the dam area on 7 September 2011
• A more detailed archaeological survey covering the larger footprint of the dam and reservoir
in January 2012. Where possible, this involved close examination of the ground surface for
evidence of former occupation or use
• A desktop assessment covering the route of the proposed headrace and associated irrigation
infrastructure.
Clough & Associates did not include an assessment of effects on Maori cultural values. Such
assessments should only be made by the tangata whenua, and Maori cultural concerns may
encompass a wider range of values than those associated with archaeological sites. These
assessments have been undertaken separately.
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24.3 Result of Assessment
No archaeological sites had been recorded in the immediate vicinity of the proposed dam and
reservoir prior to the assessment, although sites including two Maori pa are recorded approximately
7-10km away. The density of archaeological sites previously recorded in the wider area around the
proposed dam site is low.
No Maori or other pre-1900 archaeological sites were identified during the field survey. The area of
the reservoir and dam does not appear to have been a favoured location for pre-European
settlement for topographic reasons, and the tangata whenua have not identified any archaeological
sites of significance to them in the immediate vicinity. However, the possibility that pre-1900
subsurface archaeological remains may be encountered during earthworks cannot be completely
excluded.
One archaeological site of early 20th century date was identified within the RWSS area – the site of
Gardner and Yeoman’s Sawmill, located on the southern bank of the Makaroro River near Dutch
Creek. Various remains of the mill operation were noted, dating from the period 1920s-1950s.
The mill site is of local historic heritage significance based on its archaeological values, its historical
values and its educational potential. However, its heritage values are considered to be moderate
rather than high in view of its relatively late date and limited integrity. It is not scheduled for
protection on the Central Hawke’s Bay District Plan, or registered as a historic place by the NZ
Historic Places Trust.
The site of the mill would be permanently flooded by the RWSS.
No recorded archaeological sites in the vicinity of the proposed water distribution network will be
affected.
Desktop assessment did however identify a number of archaeological sites near the water
distribution channel in Zone M, east of Waipawa.
24.4 Suggested Approach for Effects Identified
As it would not be possible to protect the Gardner and Yeoman mill site in situ, the following
measures are proposed by way of mitigation:
• Archaeological investigation and further recording of the site should be carried out prior to
flooding
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• A report on the history of the mill (based on oral and archival sources) and the results of the
archaeological investigation should be prepared and deposited in the local museum and
library and the NZHPT library
• An interpretation plan should be prepared and interpretive signage detailing the location
and history of the mill should be installed in a suitable location (or locations) near the dam
and reservoir that is accessible to the public. This could be associated with the existing
Yeoman’s Track
• The boiler and any other significant industrial remains should be removed from the site prior
to flooding and deposited in a local museum or installed on higher ground nearby in a
location accessible to the public as part of the interpretation of the site.
Although the potential for archaeological remains to be exposed during construction is low, it is also
recommended that comprehensive Accidental Discovery Protocols should be developed in
consultation with the NZHPT and tangata whenua. These would ensure that if koiwi tangata (human
remains), taonga or sub-surface archaeological evidence is uncovered during construction, work
would cease in the immediate vicinity of the remains so that appropriate action could be taken. A
field survey of the water distribution network (including the Zone M channel) should also be carried
out by an archaeologist prior to earthworks as a precaution in case any unrecorded sites are present.
If modification of an archaeological site does become necessary, the effects could be appropriately
mitigated under the provisions of the Historic Places Act 1993. An Authority to modify an
archaeological site would be required before any work could be carried out that would affect an
archaeological site. It would be possible to apply for a general Authority from the NZHPT prior to
earthworks as a precaution to minimise delays should archaeological remains be accidentally
discovered.
A Workshop on a potential integrated Mitigation and Offset programme associated with the physical
effects of the RWSS on the environment was held on 6 March 2012. This was attended by DOC and
Iwi representatives as well as the authors of the recreation, landscape, archaeology and Terrestrial
ecology reports.
The recommendations contained in this report were discussed at the workshop and HBRIC Ltd have
prepared a separate report entitled ‘Ruataniwha Water Storage Scheme – Integration and Mitigation
and Offset Approach’ (HBRIC, May 2013f) which should be read in conjunction with this report.
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Proposed conditions of consent give effect to these recommendations by requiring their progressive
implementation upon commencement of construction of the Scheme, and the adherence to a
specific Cultural/Accidental Discovery Protocol.
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25 LANDSCAPE AND VISUAL EFFECTS
A study of the Scheme’s landscape and visual effects has been completed by Isthmus (Isthmus, May
2013).
25.1 Potential Environmental Effects
Potential landscape effects of the Ruataniwha Water Storage Scheme include the following:
• Potential effects on the natural character of the following rivers and their margins
The Makaroro River and its tributaries (Dutch Creek and Donovan’s Gully) as a result of
construction of the dam and inundation of the existing river
The Makaroro, Waipawa and Tukituki Rivers downstream of the dam as a result of
changes to natural flow regimes
The Waipawa River at the location of the upstream and downstream water intake
structures as a result of changes to the river bank
Smaller streams and watercourses in the Ruataniwha Plains where traversed by the
primary distribution system headrace, as a result of construction of culverts or inverted
siphons
Papanui Stream as a result of changes to the flow regime, modifications to the stream
channel, and proposed fencing and revegetation of the stream banks
• Potential effects on the outstanding natural landscapes of the Ruahine Ranges as a result of
the nearby reservoir lake
• Potential effects on landscape amenity including
Visual effects of the dam and reservoir lake
Visual effects of the primary distribution system head-race (from both private and public
views)
Visual effects of the power station and transmission line
Effects on the character of the Ruataniwha Plains and Zone M as a result of increased
irrigation (including pasture ‘greening’ and additional use of pivot irrigators)
Effects on the biophysical landscape including effects of earthworks on landforms,
watercourses, or vegetation
• Temporary construction effects.
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25.2 Assessments Undertaken
HBRC initially commissioned Isthmus in November 2011 to undertake a ‘Baseline Landscape
Assessment’ and to provide input to the refinement of the Scheme design. The ‘Baseline Landscape
Assessment’ report (Final 23 January 2012) assessed the existing landscape values, scoped potential
landscape effects, appraised alternative headrace types and alignments, and proposed a series of
principles or guidelines for the detailed design of the headraces. Isthmus participated in site visits
and workshops that addressed appraisal of alternative headrace options (types of headrace and
alternative alignments) and remediation / mitigation measures with regard the dam and reservoir.
The subsequent Landscape and Visual Assessment addressed the following matters:
• A description and appraisal of the existing landscape including
Its physical, perceptual and associative factors,
The nature and degree of natural character of the rivers and their margins; and
Identification of outstanding natural features and landscapes.
• An analysis of the effects on natural character of the rivers, including effects on both
biophysical and perceptual aspects of natural character, taking into account the inundation
of the existing river by the dam, modification of downstream flows, and the construction of
the primary distribution system including the intake and outfall structures and crossing of
smaller streams by the headrace canal
• An analysis of the effects of the dam and reservoir on the values of the nearby Ruahine
Ranges (being the only Outstanding Natural Landscape potentially affected)
• An analysis of the effects of landscape amenity and biophysical effects. Given the dispersed
nature of the Scheme this was dealt with by dividing the Scheme into its components as
follows:
Dam and Reservoir
Primary Distribution System including the Water Intake Structures, Headrace Canal and
Buried Pipelines
Secondary Distribution System and Changes to Land Use Patterns
Downstream Intake Structure and changes to the Papanui Stream
Hydro-electric (add-on) Station
Transmission Line
• An assessment of potential temporary construction effects.
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25.3 Results of Assessment
Natural Character
The main adverse landscape effect will be on natural character of the Makaroro River in the vicinity
of the dam and reservoir, and on the downstream flows below the dam. Natural character will
clearly not be preserved in the vicinity of the dam and within the reservoir footprint, and it will be
diminished to some extent on the Makaroro River (and to a lesser extent the Waipawa River)
downstream of the dam as a result of changes in flow regime and sediment load. Such effects are
common to any in-river dam.
Factors to take into account when considering the appropriateness in relation to such effects include
the following:
• The modified ‘working rural character’ of the adjacent land
• The low visibility of the dam (and hence low effects on the appearance (visual aspects) of
natural character)
• The naturalistic appearance of the reservoir
• Proposed measures as described in the ‘Proposed Integrated Mitigation and Offset
Approach’ report which will enhance the biophysical and visual aspects of natural character
of the reservoir including establishing a fenced and planted margin around the reservoir, and
measures to enhance habitat and control predators in the reservoir catchment
• Proposed management of the downstream flow regime to provide minimum low flows in the
Makaroro River, regular flushing during summer months, and biodiversity enhancement
measures in the downstream sections of the Makaroro and Waipawa Rivers
• Beach replenishment at the mouth of the Tukituki River to replace the reduction in sediment
load – to be carried out in allocation and manner that will not create any new adverse
landscape effects apart from the temporary effects of the replenishment activity.
• The low impacts of the intake and outfall structures on natural character because of their
low profiles, low visibility locations, and modified rural settings
• Positive effects on the lower Tukituki River as a result of increased summer flows and
flushing ‘freshes’
• Positive effects on the natural character of the Papanui Stream because of increased flows
which will partly restore historic flows, and the associated fencing and margin restoration;
(partly restoring the historic diversion of water from the previous course of the Waipawa
River).
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Outstanding Natural Features and Landscapes
The only outstanding natural feature or landscape in the area is the Ruahine Ranges. The Scheme will
have negligible effects on the landscape values of the Ranges because the dam and reservoir will be
in a working landscape that is clearly separate from the Ruahine Ranges, the dam itself will not be
visible from the ONL (except in very long distance views from the mountains) or from roads
providing access to the Ranges, and the upstream end of the reservoir will not be visible from where
the Makaroro River emerges from the Ranges.
Landscape Amenity and Biophysical Effects
Adverse landscape amenity effects will be low for a Scheme of this type for the following reasons:
• The dam, which is the feature with the greatest potential adverse amenity effects, will have
very low visibility. To most intents and purposes it will have no public visibility except for
future users of the reservoir
• Similarly the 6.5MW hydro power station will be a minor adjunct to the dam, and will
essentially have no public visibility. The associated 33kV transmission line will be an
unremarkable element carried on power poles along the road reserve
• While there will be some potential adverse amenity effects resulting from the seasonal bare
zone around the reservoir margins, a range of measures is proposed to mitigate such effects
• The upstream water intake structure on the Waipawa River will be tucked against a bank in
an unobtrusive location with low visibility, and similarly the downstream intake structure will
have a low profile, and will be in a low visibility location at the toe of a stopbank
• The primary distribution system headrace canal, which forms part of the primary distribution
system, will not be out-of-place in a working rural landscape (it will continue a tradition of
community water races in the area). The selected route follows the contours and traverses
relatively subdued topography so that earthworks will have low profile. The selected route
also avoids houses
• While there will be changes in land-use, field patterns and associated structures (such as
pivot irrigators), such land uses will not be dissimilar to existing activities and they will
continue a pattern of change and evolution that has characterised the landscape over the
last 150 years.
There will be some positive landscape amenity effects:
• The reservoir will have high amenity as a ‘lake’ taking into account its serpentine form,
tributary reaches, bold hill backdrop, and the re-vegetation proposed around its margins
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• The primary distribution system head race canal may also be perceived as a positive and
interesting feature
• The use of the Papanui Stream to convey irrigation water will partly restore the watercourse,
and the fencing and replanting of its banks will enhance its natural character.
The main potential biophysical landscape effects are subsumed under the topic of ‘natural character’
above. Any adverse biophysical effects in addition to those addressed under that topic will be low for
the following reasons:
• The Scheme will be within a modified working rural landscape
• Most of the water distribution network will be by means of buried pipelines
• The primary distribution system headrace canal has been aligned to follow flat to rolling
topography which will minimise the scale of the earthworks, and it traverses open farmed
country.
Temporary Construction Effects
The dam and its ancillary structures present the main potential for construction effects. However
such effects will be confined to a relatively small area with visibility essentially restricted to private
farmland.
There will be some adverse construction effects associated with the contouring and armouring of the
reservoir margins, primary distribution system headrace construction, laying of distribution system
pipelines, installing the transmission line, and constructing such elements as the intake structure and
inverted siphons. Such effects will, however, be temporary in nature, short term in duration
(construction and earthworks will be rehabilitated as the Scheme progresses), limited in scale, and
will not be out-of-place in a cultivated rural landscape.
Summary of Effects Assessment
In summary the Scheme will not be out-of-place in the landscape, the main elements have been
appropriately designed and located, and the degree of residual adverse landscape or visual effects
will be relatively modest for a Scheme of this type.
25.4 Suggested Approach for Effects Identified
Measures that are already incorporated within the Scheme design will avoid or minimise potential
adverse landscape effects. Such measures include the selected dam site and footprint of the
reservoir, the location and design of the primary distribution system including the intake structures,
headrace type and alignment, and proportion of the water distribution network that will be buried.
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Suggested further measures to mitigate residual adverse effects (and enhance amenity) include
planting around parts of the lake margin, measures (such as armouring and contouring) to
ameliorate the fluctuating water level bare zone, public amenity facilities adjacent to the lake, and
implementing the landscape principles and guidelines for the detail design of the headrace.
Landscape measures should be incorporated into an integrated design, along with measures relating
to other disciplines, as described in the parallel document ‘Ruataniwha Water Storage Scheme –
Proposed Integrated Mitigation and Offset Approach’ (HBRIC, 2013f).
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26 SEDIMENTATION EFFECTS
A report prepared by Tonkin & Taylor (Sedimentation Assessment -Tonkin &Taylor, May 2013b)
considers sedimentation effects of the Scheme.
26.1 Potential Environmental Effects
Although not specifically listed in the Executive Summary of the report, potential environmental
effects discussed include:
• The trapping and filling of the reservoir with sediment resulting in declining efficiency in
storage capacity for water, restrictions to access, upstream flooding and potential impacts
on Dam outlets
• Dust effects at times when the reservoir has low storage
• Downstream degradation and coarsening of bed sediments
• Coastal depletion of sediment load.
26.2 Assessments Undertaken
The four main aspects of the assessment scope are:
• Develop a sediment allowance for the Reservoir
• Assess the effects of the dam on downstream sediments and the coast
• Review the sediment management options
• Develop the sediment mitigation plan.
The methodology utilises the good sources of measured data that exist for the Tukituki/ Waipawa
River system. The measured data consists primarily of river cross-sections that are used to develop a
sediment budget, and the measured accumulation at Folger’s Lake. Suspended sediment yields were
estimated using the WRENZ57 model calibrated to the Waipukurau gauge (Tukituki River) and the
trapping efficiency in the reservoir based on the Brune58 method.
The changes to the sediment budget due to the Dam are quantified for each reach and the effects
qualitatively assessed. A number of reports/papers provide useful information on sedimentation for
the Tukituki/Waipawa River system, which were used where relevant.
57 Water Resources Explorer NZ 58 The Brune method applies a trap efficiency to the sediment transport of the river to calculate an annual sedimentation in
the reservoir. It is an internationally accepted methodology for large reservoirs.
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Assessments of changes to gravel transport capacity and assessments of degradation depths and
armouring effects are made.
26.3 Results of Assessment
The estimate of sedimentation in the Reservoir is 15-26 million m3 over 100 years based on a range
of estimates. These sedimentation estimates result in reservoir half full times ranging from 175 to
287 years and ultimate fill times ranging from 355 to 603 years.
There remains considerable uncertainty in the bed load estimates, which is inherent with this type of
exercise. The report’s authors consider that the lower estimate is non-conservative due to
unaccounted sediment losses in the sediment budget, and the upper estimate is conservative due to
the stormier period that was the basis of the Folger’s Lake derived estimate for bed material.
The suspended sediment estimates are from the WRENZ model based on the unscaled estimate and
the Waipukurau measured suspended sediment upscaled for the upper Makaroro catchment
characteristics, which give similar estimates.
Sediment generation is greatly influenced by extreme events such as extreme floods and/or
earthquakes and these have the ability to increase the rate of reservoir sedimentation. Similarly,
prolonged periods of quiescent conditions will reduce sedimentation rates.
A sediment delta will form within the reservoir. The physical impacts of sedimentation are loss of
storage, restrictions to access (in areas where sediment has deposited) and the potential for impacts
on the Dam outlets. These impacts can be mitigated by design. The delta and hydraulic backwater
effects from the reservoir will eventually cause an increase in flood levels upstream of the reservoir.
There are no existing bridges or river management infrastructure upstream of the reservoir that will
be affected.
When the reservoir is drawn down there is the potential for dust generation. The Dam site is remote
with few surrounding dwellings. Therefore, the potential for affecting the general public appears to
be low.
The interruption of sediment from the Dam will have greatest effect on the 12 km reach of the
Makaroro River between the dam and the confluence with the Waipawa River. The likely effects are
degradation and coarsening of the bed sediment.
These effects will be mitigated to some extent by the reduction in sediment transport due to the
armouring and the reduction in flood flows. However, the reduction in flood flows will reduce the
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ability of the flows to erode vegetation. The encroachment of vegetation will likely reduce the
channel width and form. The river will trend towards fewer channels.
There is no river management infrastructure on this reach. Therefore, changes to the channel form
and levels will have no effect on river management infrastructure. Burnt Bridge (Makaroro River)
and to a lesser extent the Wakarara Road Bridge (Waipawa River) have the potential to be affected
by lowering of bed level. These should be monitored as part of the draft sediment management
plan.
The interruption of sediment from the Dam will have a lesser effect on the rivers downstream of the
confluence of the Makaroro and Waipawa, as there will still be a surplus of gravel for these reaches
from other rivers. The interruption of sediment supply from the Makaroro River will result in less
aggradation (currently occurs) and can be accommodated by less extraction (if required). A
reduction in sediment transport capacity is predicted at the upstream water intake, which may result
in local aggradation.
An additional effect is the reduction in gravel transport capacity to the coast of 1,700 cubic metres
/year. Mitigation by coastal nourishment is proposed so that existing coastal erosion that is
occurring in the vicinity of the mouth of the Tukituki River is not worsened.
There will be a net long term reduction in the gravel resource for extraction and construction
industry purposes from the Waipawa and Tukituki. Although gravel will become available at the
Reservoir, this is further away from markets (i.e. the Dam and reservoir location is more remote than
the current extraction locations).
The ecological effects that result from the change in river morphology are described in ecology
assessments that form part of the suite of reports accompanying this Application.
26.4 Suggested Approach for Effects Identified
Sediment management options have been assessed and the preferred suggested options are
included in the draft Sediment Management Plan in the Sedimentation Assessment report (Tonkin &
Taylor, May 2013b). A summary is provided below.
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Location/ issue
Monitoring Management
Reservoir
Cross-section/bathymetry survey to monitor sedimentation and delta development. Frequency 3 years. Flow gauging of releases from the Dam.
Design Include sedimentation allowances in the volume requirement of the Dam. Design of outlet structures for sedimentation. The location of recreation areas and access points to the reservoir to consider sedimentation. Land management measures including sediment management practices for forestry areas and fire protection programmes for the Ruahine Forest Park and the commercial forestry. Medium to long-term (not included in the Application Design) Extraction of gravel for construction industry e.g. roading aggregate Hydraulic flushing of fine sediments via low outlets (would need to be provided for at the detailed design stage). Sediment focussing by in-reservoir works to manage sediment storage within the reservoir. These can consist of training banks and similar structures to enhance flushing of sediment from live storage to dead storage, and for access up-river. Closure (not included in the Application Design) Dam removal is an option to consider at the end of the operating life if required. Restrictions to access (in areas where sediment has deposited) and the potential for impacts on the Dam outlets.
Reservoir dust
Dust generation should be monitored with inhabitants provided a contact number of the Dam operator if they wish to make complaints. The operator should keep a register of complaints consistent or similar with Appendix 2 of Good Practice Guide for Assessing and Managing the Environmental Effects of Dust Emissions (MfE 2001). Copies of the register should be forwarded to HBRC for their consideration of whether further preventative action is appropriate.
Should a dust issue arise then consideration to planting shelter belts. An additional contingency measure may be to raise the minimum operating water level to cover the bottomset sediments. This would require careful consideration of secondary effects of this action including irrigation supply and residual flows.
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Makaroro River downstream of the Dam
Cross-section survey at 3 year frequency to match existing HBRC monitoring programme. Maximum spacing to match existing HBRC monitoring programme of 500 m and to include Burnt Bridge. Measure particle size distribution of bed surface particle-size distribution at three year frequency at representative and accessible locations to monitor armour development.
Respond to degradation of channel at Burnt Bridge (if required). Options include grade control (rock weir) or underpinning of piers.
Waipawa River between Makaroro confluence and SH50
Cross-section survey at 3 year frequency which is a continuation of existing HBRC river monitoring. Additional cross-sections to be included for Waipawa upstream of the Waipawa/Makaroro confluence including Wakarara Road Bridge and Pendle Hill Bridge (1 km upstream) with maximum spacing of 500 m. Additional cross-section for the Upstream Water Intake.
Respond to degradation of channel at Wakarara Road Bridge (if required). Options include grade control (rock weir) or underpinning of piers. The long term reduction in extraction (if required) based on monitoring in accordance with current HBRC flood and sediment management practices. Extraction of excess gravel at the irrigation intake and elsewhere in accordance with HBRC river management practices. Optional spraying and raking of gravel beds to increase the supply of gravel (if required). Significant accumulation of gravel has occurred in this reach.
Waipawa/ Tukituki Rivers downstream of SH50
Cross-section survey at existing cross-section locations at 3 year frequency, which is a continuation of existing HBRC river monitoring.
Normal river management practises undertaken by HBRC. The long term reduction in extraction (if required) based on monitoring in accordance with current HBRC flood and sediment management practices, refer to Section 3.5 for details.
Coast Cross-section surveys at existing cross-section locations, which is a continuation of existing location and frequency of HBRC coastline monitoring.
Beach nourishment of 3,400 cubic metres /year comprising of 1700 cubic metres /year of river sediment placed within the Coastal Marine Area directly along the barrier beach between Richmond Road and School Road extension and an additional 1,700 cubic metres /year to the south along the spit. Review the beach nourishment requirements based on updated assessments of reduction in capacity (and renourishment needs) due to the Scheme using the consented reservoir operating regime. Review to be based on monitoring and modelling at year 3 and at subsequently at nine year intervals. Changes in beach nourishment to be approved by HBRC manager.
Tukituki River basin
Cross-section monitoring (as above), selected PSD sampling, sediment and flow gauging.
Morphological model be developed for the Tukituki River basin including Waipawa and Makaroro Rivers.
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The proposed conditions in Part D require preparation and implementation of a Sediment
Management Plan referenced to the report recommendations.
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27 DAM BREAK STUDY
The Scheme consists of a large water storage reservoir created by a proposed dam on the Makaroro
River, as well as associated works used to distribute the water to downstream locations. A Dam
Break analysis for the Scheme has been completed by HBRC Asset Management Group (HBRC
Engineering, May 2013).
The report provides analysis and results showing the consequences of the failure of the Dam during
its operational phase. The dam break analysis is entirely hypothetical and divorced from the actual
probability of a dam failure occurring, and is not instigated by any particular concern with the
conditions at the dam site or the proposed concept in the construction of the dam.
The dam break analysis is used to assist in determining the Potential Impact Category (PIC) of the
dam, based on an assessment of the potential downstream effects in terms of potential loss of life,
as well as damage to infrastructure in the event of a dam failure. The results of this analysis indicate
the proposed dam will be a HIGH PIC dam.
27.1 Potential Environmental Effects
Failure of the main dam after completion of construction, and assuming the reservoir is full, would
likely result in significant damage to infrastructure (bridges, roads, stopbanks, and sewage treatment
plants), environmental damage to the river corridor and surrounding floodplain, and involve a
population-at-risk of approximately 1000 people.
27.2 Assessments Undertaken
The assessment of the potential downstream effects of a dam break consists of three parts:
1. Determination of the dam breach discharge hydrograph,
2. Determination of the extent and timing of the flood wave,
3. Assessment of potential impact category (PIC).
The HBRC Engineering (May 2013) report outlines the method used in the analysis, and then
presents the results with maps showing the timing and extent of the flood wave as it travels down
the river system.
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27.3 Results of Assessment
Results indicate the flood wave would be contained in the incised river sections of the Makaroro and
Waipawa Rivers downstream of the dam until around SH50. Downstream of SH50 there would be
significant overflows on the left and right banks of the Waipawa River.
On the left bank of the Waipawa River, downstream of SH50, the overland flow spreads out over a
wide area and travels towards the Mangaonuku Stream, at which point it is confined and flows back
into the Waipawa River.
On the right bank of the Waipawa River, downstream of SH50, the overland flow travels to the
Kahahakuri Stream and the Tukituki River, and then overtops the stopbanks on the Tukituki River
around Waipukurau.
Downstream of the Waipawa/Mangaonuku confluence, the Waipawa River narrows again, forcing all
the water through a confined section, then the flood wave overtops the stopbanks at the town of
Waipawa. Water depths in the area of Bibby Street near the Waipawa sewage treatment works
(oxidation pond) would likely be in the order of 3 m to 5 m deep.
Another overflow occurs downstream of the town of Waipawa, just after the confluence of the
Waipawa and Tukituki Rivers, down an old course of the Waipawa River to the Papanui Stream. The
Pukehou and Te Aute swamp areas become inundated in this scenario, due to their low lying nature.
Downstream of the confluence with the Papanui Stream, the flood wave is fully contained within the
Middle Tukituki River channel.
At the mouth of the Lower Tukituki River, there would likely be high water levels in Grange Creek
near Haumoana, with similar levels to those from a 50 year return period event in the Tukituki River.
The scenario analysed for the PIC determination produced a peak discharge of around 45,000
cumecs at the dam site. Due to the topography of the river channel, the flow is fairly quickly
attenuated. However, the results indicate a peak flow of around 10,400 cumecs is still likely in the
Waipawa River near the town of Waipawa. This is an area with stopbank protection up to the 100
year return period event, which has an estimated design discharge of 1350 m3/s, i.e. the flood wave
has a peak discharge that is roughly eight times the 100 year discharge at this location.
The peak of the flood wave takes approximately 13 hours to travel from the dam site to the coast, a
distance of about 116 km. There would likely be a minimum of two to three hours warning time
between the initiation of failure and the time when the population and infrastructure of Waipawa
and Waipukurau were at risk.
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27.4 Suggested Approach for Effects Identified
Due to these potential risks, along with the size of the main dam, the PIC of the main dam is
determined to be high. The primary mitigation of the potential effects from an unlikely dam break
event is the adoption of the highest standards for design, construction and operation to ensure that
the probability of failure is extremely small related to the degree to which the potential impact is
high. In addition to minimum standards for design, a High PIC dam will require an appropriate Dam
Safety Assurance Programme (DSAP) under New Zealand‘s Dam Safety Regulations. Part of the DSAP
will be an Emergency Action Plan (EAP) that will detail the actions that the owner, operations
personnel and relevant Government and Local Authorities should take if an incident or emergency
develops that threatens the safety of the dam. Both the DSAP and EAP will be required prior to
commissioning of the dam.
The requirement for an EAP forms part of the conditions contained in Part D – Proposed Consent
Conditions.
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28 COMMUNITY ENGAGEMENT
28.1 Introduction
Community engagement with the Scheme was established early on in the process, and included
development of two formal groups, the Leadership Group and Ruataniwha Stakeholder Group, to
assist and advise the Project Team throughout the pre and full-feasibility phases of the project. The
structure and role of these groups is further outlined in the sections below.
Public meetings, media releases, field days and speaking engagements have also allowed the public
to remain informed of the Scheme over time. Many groups and organisations such as Rotary, Fish &
Game, Department of Conservation, Mana Whenua and Forest & Bird have had site visits and/or
presentations; and Territorial Authority staff and elected officials have been provided with regular
updates on the Scheme and invited to attend field trips as they are arranged. Table 28.3.2 provides a
summary.
28.2 Leadership Group
The Leadership Group was established in April 2010 to champion, govern and guide the feasibility
Scheme; and to ensure that the correct market, economic, commercial, risk and benefit/cost
questions were asked and systematically addressed so that the feasibility (including scale, extent and
timing) of the Scheme could be determined.
Sam Robinson, a Central Hawke’s Bay farmer and Chair of AgResearch, was appointed to Chair the
group. Other members include representatives of the business and farming communities, Mana
Whenua and Regional Council elected officials. Debbie Hewitt, the Chairman of the Ruataniwha
Stakeholder Group is an active participant in the group discussions but remains independent of
group decisions.
Throughout the feasibility phase of the project, the Leadership Group generally met on a bi-monthly
basis, or as required in order to advise on process at key points. Table 28.2.1 lists the dates and
location of Leadership Group meetings held.
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Table 28.2.1 Leadership Group Meeting Summary
Date Location
13 April 2010 Council Chamber, HBRC
2 June 2010 Council Chamber, HBRC
2 August 2010 Council Chamber, HBRC
12 October 2010 Council Chamber, HBRC
10 March 2011 Council Chamber, HBRC
18 August 2011 Council Chamber, HBRC
31 October 2011 Council Chamber, HBRC
29 March 2012 Council Chamber, HBRC
25 June 2012 Council Chamber, HBRC
14 August 2012 Council Chamber, HBRC
19 September 2012 Council Chamber, HBRC
28.3 Ruataniwha Stakeholder Group
The Ruataniwha Stakeholder Group was established in April 2010 to share information and identify
and explore community expectations on water management for the various uses in the Upper
Tukituki catchment, specifically on the Ruataniwha Plains. The group’s role also includes assisting
with identification of the value of water to the whole community and in coordinating more effective
stakeholder input into water management decision-making processes for the Plains. This includes
providing guidance to the development of the Scheme in a collaborative way, with specific emphasis
on environmental, social and cultural elements of the Scheme.
Debbie Hewitt, a Director of Horticulture NZ and a Central Hawke’s Bay farmer, Chairs the group,
which includes representatives from Fish & Game, Forest and Bird, Department of Conservation,
CHBDC, HBRC, Tukituki Liaison Group; as well as Mana Whenua, landowner, recreation clubs, and
water user group representatives.
During the advanced pre-feasibility phase of the Scheme, Stakeholder Group meetings were held bi-
monthly. This was increased to 6-weekly intervals during the full feasibility phase (June 2011 –
August 2012). Table 28.3.1 summarises the Stakeholder Group meeting schedule and key topics
discussed during each meeting.
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Table 28.3.1: Summary of Stakeholder Group Meetings and Key Topics Discussed
Date Summary of Meeting
6 May 2010 - Presentations on Regional Water Management Strategy, Tukituki Liaison Group, North Otago Farm – Audit Report, HBRC – Regional Strategic Water Demand and Availability Study, Science Programme
- Terms of Reference discussed
22 June 2010 - Scheme Update - sites removed from Scheme due to geotech work/seismic activity
- F&G indicated Trout spawning site in Dutch Creek - HBRC presentation on RC Science work - Update on 31 May Landowner Meeting - Group reminded this is a two year process
10 August 2010 - Scheme Update – Ruataniwha GW model completed by HBRC Science, trend showed decreasing availability of water for irrigation and other uses
- Hapu site visit took place 7 Aug - Latest dam sites map displayed - Project Timeline circulated. - Opuha Irrigation System & Dam (Rural Delivery TV) shown to group. - Presentation from DOC on Canterbury Experience
26 October 2010 - Scheme Update – National Land & Water Forum Report discussed - Regional Councils’ position paper on National Water Strategy discussed. - Debbie Hewitt to present at HB Regional Water Symposium - Presentation on Ruataniwha soil types - Presentations by Dan Bloomer & Chris Perley – Land Use Options & A Strategic
View
1 February 2011 - Update on D5 & A7 sites, significant fault lines outlined in Ruataniwha Basin. Science Presentation on Tukituki hydrology and gw/sw interaction
- Stakeholders asked for their Key issues - Costs, gravel, recreation , land use balance, keep the information flowing, environmental impact, how will best practice be enforced, see working in partnership – a Kaitiaki role
- We don’t have all the answers today, feasibility process will go for next 18 months
3 Jun 2011 - Schemes relationship with the media questioned - Sam Robinson, Chairman of RWS Leadership Group briefed the group - Cultural Impact Assessment study presented by Dr Benita Wakefield - Engineering Work programme – tender issued - Environmental Work programme – Eight Environmental work scopes presented
6 July 2011 - Update on Council approved funding & MAF funding for next financial year. - Technical Feasibility Update – Makaretu site drilling uncovered previously
unknown aquifer. Expansion of drilling programme at Makaroro site - Environmental Work Programme – Tenders for Aquatic & Terrestrial work
scopes closed today - Glen McLean appointed to undertake Spawning Survey. - Non-Physical Science Study Scopes outlined
19 August 2011 - Dam Engineering Update – D5 site no longer being investigated due to complex geotechnical discoveries. New footprint for A7 site shown
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- Updates provided on Ecology Studies, Spawning Survey, Social Impact Assessment, Mana Whenua Communications, Communications Strategy
6 October 2011 - Scheme Update – Drillers on site, 2 more potential irrigation zones M & N being considered, Land Use Intensification Study commencing
- Update on Expectations for Current Consent Holders - Mana Whenua Values Setting Study – for wider plan change work commencing - Social Impact Assessment presentation by Nick Taylor - Update on Tukituki Regional Plan Change and Community Engagement - Communications Strategy outlined
22 November 2011 - Scheme Update – Tonkin & Taylor Ltd Initial Project Description draft report received - exec summary to be provided to Stakeholder Group.
- MAF representatives to meet with Council on funding - HBRC to have stand at CHB A & P Show - 2nd HB Land & Water Symposium announced for 30 November. - The “Risks” reiterated – Technical/Geological, Land Use Intensification, Change
process for Consent Holders, Uptake Risk - Nominations asked for LUI steering group
10 February 2012 - Scheme Update – HBRC attending workshop on reticulation and refining costs. - Hydro Power evaluation being undertaken - MAF funding secured through to end of feasibility stage. - LUI update received - Update on Study scopes received - Presentation by Nick Taylor – Social Impact Assessment - conclusion Irrigation
brings as important range of potential social-economic benefits that can enhance social and economic wellbeing
- Finance and Business modelling update by Andrew Newman
22 March 2012 - Scheme Update – Timelines discussed may mean push from June to August - Helen Codlin on Tukituki Plans Change – critical timelines to be in line with
Water Storage Scheme, Stakeholder Group to be kept informed of key issues. Stakeholder members received feedback from community on recent “Consent Holder Newsletter”
- Iain Maxwell gave update Water Quality programme – specifically nitrates and phosphorus
- Presentations received from Gavin Lister, Isthmus Group on the Landscape Study, Simon Bickler, Clough & Associates – Archaeology, Michele Frey, Opus – Recreation Study
- Update from LUI working party
27 April 2012 - Combined Leadership / Stakeholder Group meeting to be arranged. - A clear summary of studies to be provided - Updated Gantt chart circulated - project timelines pushed out to August. - Estimated cost for a piped distribution noted $30 mil. This on top of the est.
$230 build cost - Presentation on Noise Assessment study and Traffic/Roading Study - Presentation on NIWA report on Reservoir Water Quality - Gerry Kessels presented his Terrestrial Ecology Report - Update from LUI working party
14 June 2012 - Feedback received on Terrestrial Ecology Report - Scheme Update – Zones M & N engineers currently reviewing. Construction of
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distribution network would be driven by uptake - Tukituki Cultural Values & Uses Assessment presented by Marei Apatu and Dale
Moffatt of Te Taiwhenua O Heretaunga - Update from LUI working party - HBRC Draft Ground Water/Surface Water Resource Report presented by Iain
Maxwell and Rob Waldron
25 June 2012 - Presentation on HBRC Water Strategy, integration of Tukituki Plan Change and Water Storage Scheme
- Group discussed EPA, making submissions, timelines - Presentation on Tukituki Choices, consultation process - Group discussed cost, ownership, employment, investment, consenting process
27 July 2012 - Overview given of next phase - Discussion on Feasibility Summary Report - Small Scale on Farm Water Storage - Presentation on Tonkin & Taylor Ltd Sedimentation Report - Presentation on Dam Break Analysis by Craig Goodier - Update from LUI working party - Presentation of Cawthron Aquatic Ecology Report by Roger Young from
Cawthron - Presentation of Mitigation Offset Report by Larissa Coubrough - Overview of Tukituki River Catchment Cultural Values & Uses Report by Benita
Wakefield - Update on Communication Activity
31 August 2012 - Scheme Update – science caucusing proposal, final aquatic ecology and mitigation/offset reports.
- LUI final update and presentation of final Working Party report for members signatures
- Draft Feasibility Environmental Summary Report to Council and completion of decision matrix
- Discussion on position of cadmium as part of nutrient management discussion. - Economic overview from Macfarlane Rural Business Ltd – Review of Farm
Profitability Report - Presentation on Tukituki Choices document and process - Discussion on Stakeholder Group future
14 December 2012 - Scheme Update provided including proposed timelines through 2013 - Presentation on the draft Tukituki Plan Change (A draft version had been pre-
circulated) - Discussion on environmental reporting for the EPA process and opportunities
for further involvement - Presentation from EPA on likely process if the Tukituki Catchment Proposal is
called in - Outline provided on the HBRIC / HBRC relationship going forward - Interest canvassed for further discussions on the Mitigation and Offset
Approach and Production Land Use Condition Development in the New Year - Update provided on the establishment of the Mana Whenua Working Party
28 March 2013 - Scheme Update on landowner meetings, procurement, building consent, Mana Whenua Working party process and the necessary DoC permissions
- Outcomes of conditions discussions with the Key Farmers Reference Group and
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Pan Sector Groups were discussed - Update on Plan Change 6 including confirmation that it was being notified on 4
May 2013 - Update on the RWSS EPA documents which had been sent to the EA as Final
Drafts for their completeness check - Progress on Farmer uptake discussed - HBRIC update including appointment of cultural, engineering and financial
advisors - Questions raised regarding media comment
A feature of the Stakeholder Group engagement has been the active participation of a number of the
key Stakeholders in the development and refinement of the Integrated Mitigation & Offset Approach
detailed in (HBRIC 2013f). This has involved Workshops in March 2012, January 2013 and April 2013
which provided valuable assistance to the applicant’s team preparing this report in terms of the
detail and focus of the package. At the most recent workshop there was agreement regarding the
concept that Mana Whenua would be an appropriate party to implement the contracts for the 5
projects and the role of the Ruataniwha Biodiversity Advisory Board was discussed in this context.
Also at this meeting, representatives of Te Taiao Hawke’s Bay Environment Forum tabled some
comments from Dr Amelia McQueen on the detail of the Terrestrial Ecology Assessment (Kessels &
Associates, May 2013). It has been agreed that a further meeting with Te Taio Hawke’s Bay
Environment Forum and HBRIC Ltd representatives will be held in May 2013 to which Dr McQueen
and Mr Kessels will be invited to discuss these outstanding issues.
Table 28.3.2 below sets out other Community Engagement.
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Table 28.3.2: A Summary Outline of Community Engagements Held Since 2009.
Meeting Type/Organisation Date Location(s)
CHBDC & HDC meetings June 2009 – August 2012 CHBDC; HDC; Dam Site
Various public meetings (approx. 10) July 2009 – September 2012
Various Hawke’s Bay Locations
Potentially Affected Landowner meetings (group and one-on-one meetings – approx. 20)
September 2009 – August 2012
Various locations, Central Hawke’s Bay
Various Forest and Bird meetings (e.g. CHB, Hastings and Havelock North Branches)
October 2010 – April 2012
Waipukurau Hastings & Havelock North
Regional Water Symposiums 31 November - 1 December 2010 & 30 November 2011
Napier War Memorial Conference Centre
Grasshoppers Visit January 2012 Wakarara Road & Wallingford Station
Nga Kaitiaki o te Awa a Ngaruroro @ Love Our River Day
18 February 2012 Kuripapango
Greenmeadows Rotary 21 March 2012 Taradale Town Hall
Green Party 19 April 2012 Napier
HB Chamber of Commerce 21 June 2012 Hettinga Estate
CHB Anglers 4 July 2012 CHB
Fish & Game Board HB 29 November, 11 & 17 July 2012
Fish & Game HB
Professional bodies (e.g. IPENZ HB, Contractors Federation)
July 12 – September 2012
HBRC
Maori Party 4 September 2012 Napier
HB Chamber of Commerce Business Breakfast
27 September 2012 Hastings
NZTA 4 October 2012 Napier
Sector Group Market/Science meetings including financial institutions (>100)
2010 – 2013 Various locations, New Zealand
Pan Sector Group meetings (6) March 12 – January 13 Various locations, Napier
Meetings with Mana Whenua (>30) 2009 – 2013 Various locations, Hawke’s Bay
Farm Advisors Forum 18 December 2012 Various locations, CHB
Farmer Forums 19 December 2012 Various locations, CHB
EPA 14 January 2013 Napier
DOC 28 January 2013 Napier
Business HB 14 February 2013 Hastings
Ingenium Conference 15 February 2013 Napier
Farmer Forum 15 February 2013 Tikokino
Farmer Forum 1 March 2013 OngaOnga
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NZTA 6 March 2013 Napier
Zone M Headrace Meeting 8 March 2013 Otane
NKII Fish Hook Summit 7 March 2013 Napier
Mana Whenua hui-a-hapu 27 March 2013 Waipawa
Business after 5 Presentation 9 April 2013 Napier
28.4 Landowners in Main Scheme Infrastructure Areas
Landowner meetings have been scheduled as required throughout the course of the pre-feasibility
and full feasibility phases of the Scheme in order to keep potentially affected landowners informed
of progress and key decision points. A feature of the consultation process is that the changing
dynamics of the Scheme since its inception has meant information has been quickly superseded. The
importance of keeping all landowners in the region as up-to-date as possible on the Scheme has
been an important albeit challenging objective.
At the end of the pre-feasibility phase of investigations one on one meetings were held with those
that owned land in locations of the proposed storage sites to inform them of the Scheme. During
the advanced pre-feasibility phase Council kept in telephone contact with landowners potentially
affected by the Scheme and advised individuals as sites were discounted. The first HBRC-run
landowner meeting was held at Ongaonga Golf Club on 31 May 2010, and was attended by
approximately 50 landowners. During this key meeting, two landowner representatives (Andrew
Watts and Duncan Holden) were voted onto the Ruataniwha Stakeholder Group to represent the
interests of affected landowners from that point forward. Successive landowner meetings were held
in January and July 2011 and March 2012 to update landowners affected by the dam/reservoir area
on Scheme progress and to enable any concerns to be raised and addressed.
Tonkin & Taylor’s Feasibility Project Description (June 2012) provided the certainty required, in terms
of the proposed Zones A to D Primary Distribution System (headrace canal and primary pipe route),
to enable Council to approach landowners potentially affected by the scheme distribution system;
and one-on-one meetings with affected landowners on the proposed headrace route were carried
out in July and August 2012.
During November and December 2012 further on-farm meetings were held with many of the
landowners affected by the Zones A to D Primary Distribution System in order to refine the
alignment further to accommodate landowner preferences. Based on these discussions the Scheme
engineers were requested to amend the Zones A to D Primary Distribution System and this is
reported and shown on 14 drawings in Tonkin & Taylor (May 2013a).
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In early 2013, HBRIC Ltd engaged The Property Group Ltd to assist with the landowner and property
aspects of the Scheme and during the first half of March 2013 Graeme Hansen (RWSS Project
Manager), and Rebecca Mackenzie from the Property Group met with all of the property owners
within the dam and reservoir footprint and the Zone A to D Primary Distribution System at their
properties. Follow-up meetings with several of the landowners on the Zones A to D Primary
Distribution System continued through March and April 2013, with the result that further changes to
the canal alignment have been made and an agreement to fully pipe the headrace in Zone A reached.
These changes are reflected in the final Notice of Requirement Plans in Part B.
Further discussions were also held with all of the landowners surrounding the reservoir through
March and April 2013 discussing detailed issues associated with the maintenance and potential
enhancement of public access and areas that may be available for offsetting purposes.
These discussions have all been positive and are part of an ongoing process associated with property
access and compensation.
28.5 Land Use Intensification Working Party
To assist HBRC and its consultancy team in the tasks associated with Land Use Intensification in
particular, the Land Use Intensification Working Party, comprising nominated members of the
Ruataniwha Stakeholder Group, HBRC Staff and consultants was established in November 2011.
Ruataniwha Stakeholder Group members nominated onto the Working Party were Hugh Ritchie,
Campbell Chard, Peter McIntosh, Benita Wakefield, and Tom Belford. The nominated Working Party
members represented a range of interest groups; two farmer representatives (cropping and dairy),
Fish & Game, Te Taiwhenua ō Tamatea, and a Lower Tukituki representative.
The primary objective of the group was to provide an interactive working forum to follow the
development and application of the Ruataniwha Land Use Intensification Model; providing input into
the development and testing of potential on-farm and off-farm means of managing and mitigating
the effects of existing land use and intensification.
The group met on a monthly basis between January and August 2012, with two meetings held in
August.
The group’s final meeting for this phase of work was held on 17 August 2012. The Working Party
prepared a report summarising their key findings and recommendations for future work around
intensification, and this was presented to the Stakeholder Group at their 31 August 2012 meeting
with the recommendations reported in the September 2012 Feasibility Report to Council.
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These recommendations included:
• Convening a caucus of water quality experts to discuss nutrient management
• Reconvening the Working Party to work with the HBRIC team to provide input to proposed
resource consent conditions.
At the 31 August 2012 Ruataniwha Stakeholder Group meeting all parties, apart from Fish and Game,
participated in a process to capture the general position of the parties as reported in Appendix Four
of the September 2012 Feasibility Report to Council.
At that same meeting all parties participating in the Land Use Intensification Working Party process
have agreed with the working party’s recommendations and signed off the final report with the
exception of Fish and Game who made the following formal statement subsequent to the meeting.
“Hawkes Bay Fish and Game has not signed the final report from the Land Use Intensification
Working Party. Fish and Game has concerns regarding some of the content including records
of minutes, and the current proposed approach of the Regional Council to set in-stream
nitrogen levels at toxicity standards. The report is a mix of process, administrative, and
outcome statements which should stand on its own merit. Fish and Game has fully
participated in the process from the outset, appreciates the efforts made by the Regional
Council to engage, and will be confirming its position on the project at the appropriate time
once it is fully informed on the issues.”
At the 14 December 2012 Ruataniwha Stakeholder Group meeting, parties interested in participating
in a conditions reference group associated with Production Land Use conditions and the
environmental mitigation and offset approach were asked to contact the RWSS project team.
Several parties expressed interest in these ongoing consultative processes at the meeting and,
subsequent to the meeting, Fish and Game sought involvement in both processes.
Due to the “holding stance” taken by Fish and Game in the prior collaborative processes described
above the HBRIC team decided that it would be unfair to the other parties who had signed off on the
Land Use Intensification Working Party recommendations to have Fish and Game at the table.
Instead a Key Farmer Reference Group (discussed below) was established to be the sounding board
for the proposed Production Land Use Consent conditions as they evolved through the early part of
2013.
It was made clear to Fish and Game that the organisation was welcome to participate in the
environmental mitigation and offset process but they declined early in January 2013 stating:
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“While Fish and Game has an interest in discussing potential mitigation options in regards to
the Ruataniwha irrigation project, we are concerned that attempts to resolve a mitigation
package and establish an implementation board at this stage in the process are premature.
The process of putting together a mitigation package requires a very clear understanding of
the proposed activity, identification of the significance of adverse effects, whether those
effects can be avoided or remedied, then finally identification of the remaining losses and
application of a clear methodology to value those losses. Because the region has not
produced an application yet, nor laid out the proposal in detail, or voted to lodge the Tukituki
Plan, the impacts of the proposal remain uncertain, and a meaningful mitigation programme
cannot be developed.
The technical work done to date is shallow at best and is a long way off defining the losses
that will occur. For example, the region plans to inundate a scenic reserve, prevent fish
passage, demolish a relatively rare remnant of forest type, remove the habitat for six
endangered species, and further degrade water quality in the catchment. Impacts in relation
to water quantity, hydrology, and Natural Character all remain uncertain.
While Hawkes Bay Fish and Game accept that a mitigation package will be required to
address residual effects that cannot be avoided or remedied, it is our position that it needs to
be evaluated in the light of the application you make. Following review of the final
application, and supporting technical reviews, Hawkes Bay Fish and Game will be in a
position to engage in an informed detailed discussion with the Regional Council around
mitigation and offset packages.”
Subsequently the Managing Director of HBRIC Ltd invited Fish and Game to engage with the
applicant following completion of the applications, this Assessment of Environmental Effects and the
supporting reports to Final Draft stage, while the EPA undertook its pre- application completeness
checks.
A meeting was held between HBRIC Ltd and Fish and Game representatives on 24 April 2013 where it
was agreed to record that the parties were back in discussions regarding the Scheme and Change 6.
28.6 Mana Whenua
Having local Mana Whenua representatives on the Stakeholder Group, and Professor Roger Maaka
as a member of the Leadership Group, has allowed for good communication with Mana Whenua
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throughout the feasibility stage of the RWSS. HBRC’s Maori Committee, and the recently expanded
Regional Planning Committee, has provided two further forums for sharing of information.
A number of Maori organisations have been engaged in the RWSS over time:
• Rakautatahi, Rongo o Tahu (Takapau area), Mataweka and Tapairu (Waipawa area) marae
– represent Mana Whenua within the Scheme area and have all marae have been visited
with presentations provided and an opportunity provided to ask questions. These marae are
also represented by members of the Mana Whenua Working Party.
• Te Taiwhenua ō Tamatea – represent all Central Hawke’s Bay marae and has been
represented on the Ruataniwha Stakeholder Group
• TeTaiwhenua ō Heretaunga – represent all marae in the Lower Tukituki catchment
• He Toa Takitini – are the claimant group for the Hastings and Central Hawke’s Bay marae.
This group will eventually be replaced by a post-settlement governance entity, which will
provide the vehicle by which any settlement sponsored investment would be channelled. It
is estimated that settlement will take place around 2013-14
• Ngati Kahungunu Iwi Incorporated (NKII) – manages fisheries assets on behalf of iwi and has
a holding company that deals with NKII investments. The group is interested in water
management in general and has a representative on the Mana Whenua Working Party. The
group may also have a future interest in investing
• Aorangi Maori Trust Board – formed in 1958. The Board manages assets on behalf of the
Takapau hapu that came from compensation for the Aorangi land block (land around
Oruawharo). The Board has no current interest in the Scheme but as a statutory body that
represents local hapu, may potentially be an investor in future.
Two Cultural Impact Assessments (CIAs) were initially completed during the advanced pre-feasibility
phase of the Scheme, providing technical information from a tikanga Tangata whenua perspective
and identifying areas of cultural significance within the footprint of the proposed storage area.
In June 2012 a’Cultural Values and Uses of the Tukituki Catchmen’ report (Te Taiwhenau ō Tamatea
and Te Taiwhenua ō Heretaunga, June 2012) was completed. The report, which was jointly
commissioned as part of the Change 6 and the RWSS feasibility processes, was completed by Te
Taiwhenua ō Tamatea in partnership with Te Taiwhenua ō Heretaunga. The assessment report
describes the cultural values and uses of the wider Tukituki River and Catchment, pulling together
the key points and recommendations from the two previously completed CIAs also. As part of this
process Te Taiwhenua ō Heretaunga produced their own report entitled ‘Ko Wai Ka Hua – Cultural
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Values and Uses, Cultural Impact Assessment Report of the Lower Tukituki Catchment’ (Te Apatu &
Moffat, 2012). The key findings of this report were presented to the Stakeholder Group at their
meeting of 14 June 2012 by Marei Apatu and Dale Moffatt from Te Taiwhenua ō Heretaunga.
The presentation highlighted the relationship of all hapu residing in the Tukituki catchment,
emphasising that the importance of the Awa cannot be differentiated between the upper and lower
catchments of the river. The importance to Maori in being able to express their relationship and
values within the Tukituki River Catchment through concepts such as mauri, mana whenua and
kaitiakitanga was also acknowledged.
At the 27 July 2012 Ruataniwha Stakeholder Group meeting the co-ordinating author for the
‘Cultural Values and Uses of the Tukituki Catchment’ report, Dr Benita Wakefield provided an
overview of the report and answered a number of questions regarding the Scheme from the Mana
Whenua perspective.
At a meeting in November 2012 involving representatives of HBRIC Ltd, Te Taiwhenua ō Tamatea and
Te Taiwhenua ō Heretaunga, a working party was established to advise on how best to implement
the recommendations associated with the Scheme that are discussed in the preceding sections.
Working party members were agreed as follows:
Member Background
Professor Roger Maaka Rongo o Tahu Marae representative and Chair of Te Taiwhenua ō Tamatea.
Spokesman for the four CHB Marae ( two each in Waipawa and Takapau)
Dr Adele Whyte Director of Fisheries and Environment, Ngati Kahungungu Iwi Incorporated
Peter Paku Ruahapia Marae, Te Taiwhenua ō Heretaunga
Des Ratima Nga Marae ō Heretaunga
Mike Mohi HBRC Maori Committee Chairman
Nga Whenua Rahui
Brian Gregory Tapairu Marae
Graeme Hansen Group Manager – Water Initiatives HBRC
RWSS Project Manager, HBRIC Ltd
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Stephen Daysh Director Environmental Management Services Limited
Consenting Manager for RWSS
Martell Letica Senior Consents Officer HBRC
Secondment to RWSS Project Team, HBRC
The Working Party objectives have been agreed as:
• To provide a forum for discussing the recommendations associated with the proposed RWSS
contained in the “Tukituki River Catchment Cultural Values and Uses” Report, June 2012.59
Three prior cultural evaluation and assessment reports60 gave background to this June 2012
report
• To facilitate any necessary presentations to the Working Party from experts associated with
effects of specific interest to Mana Whenua
• To prepare an agreement between the parties, including:
An agreed position on how to appropriately implement the ‘Tukituki Catchment Cultural
Values and Uses’ Report recommendations (including, but not limited to, resource
consent conditions)
Defining employment and economic opportunities which may be able to be
accommodated through the RWSS.
During the early part of 2013 HBRIC’s proposals for water distribution within Zone M were
developed and this is reported in EMS (May 2013a). A draft of that report was circulated for
landowner and Mana Whenua consultation purposes at the end of February 2013 and an on-site
meeting held on 8th March 2013. Following that meeting it was agreed with the Mana Whenua that
a further CIA addendum should be prepared for the Zone M / Papanui Stream area and this has been
completed (refer to Section 18.6 of this document).
The work of the Mana Whenua Working Party is ongoing at the time of lodging these applications. It
had initially been planned to conclude this with a Working Party Report at the end of April 2013 but
at a meeting held on 4 April 2013 the working party members agreed that the working party process
59 This report is included in the suite of documents accompanying this application as Te Taiwhenua ō Tamatea and Te Taiwhenua ō Heretaunga June 2012 60 “Cultural Impact Assessment of the Tukituki Proposed Water Srorage Dames” 10 September 2010 “Cultural Impact Assessment of the Tukituki Proposed Water Storage Dams: Supplemntary Report on the Mākaretu and Mākāroro Proposed Dam Sites”, March 2011 “Cultural Values and Uses, Cultural Impact Assessment Report of the Lower Tukituki Catchment” May 2012 “ Ko wai ko hua – Tukituki River Catchment Cultural Values and Uses”, June 2012
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should be extended to the end of June 2013 to provide more time to carry out some face to face hui
at those marae with an association with the Tukituki River.
At the previous meeting held on 21 March 2013 a number of matters were discussed as items which
could form an MOU / Agreement in terms of Mana Whenua interests. These included:
a) The promotion of resource consent conditions by HBRIC Ltd to cover involvement of Mana
Whenua in cultural monitoring, accidental discovery processes and environmental matters
b) The provision for employment and business opportunities in the D&C contract phase
c) Giving Mana Whenua “first right” to undertake the kaitiaki contracts outlined in the
Integrated Mitigation and Offset Approach (HBRIC – May 2013f)
d) Provision for training scholarships
e) The avoidance of commercial / monopoly ownership of the Scheme with a desire to have
ownership in Council / Maori control in the long term.
These matters are all part of an on-going discussion with the Mana Whenua Working Party, with an
expectation that an agreement may be able to be reached prior to submissions closing on the
Scheme applications.
Although represented on the Mana Whenua Working Party, Ngati Kahungungu Iwi Incorporated has
recently sought to engage separately with HBRIC Ltd. The initial correspondence emphasised the
need for Ngati Kahungungu Iwi Incorporated to be able to communicate with Iwi, Hapu and Whanau
regarding all aspects of the scheme and sought a six month deferral of submission of the Scheme
applications. This has not been agreed as HBRIC Ltd saw the extended working party process as an
appropriate means of further engagement. Subsequently Ngati Kahungungu Iwi Incorporated has
sought the opportunity to meet face to face with Directors of HBRIC Ltd and this is being planned for
the near future.
28.7 Pan Sector Group
A Pan Sector group was established in early 2012 to facilitate input into the RWSS and the proposed
Change 6 processes, by industry and academic organisations. At a high level, the group’s role is to
assist and coordinate the maximum sustainable benefit from the Ruataniwha Plains, recognising that
a collaborative approach is required to realise the potential environmental, economic and social
gains possible for the region.
The group includes representatives from: Fonterra, Silver Fern Farms, McCain Foods, Foundation for
Arable Research, AgResearch, Massey, Ministry of Primary Industries, Zespri, HortNZ, Federated
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Farmers, DairyNZ, Beef and Lamb, Heinz Watties, Fert Research, Plant & Food, Irrigation NZ, PipFruit
NZ, Rural Futures, NZ Wine Growers, and HB Fruit Growers; as well as Hawke’s Bay farmers.
Since its establishment, the group has been actively involved in the land use intensification work, and
in developing the nutrient management framework proposed through the Change 6 process. The
Pan Sector group has met on six occasions to-date, and this group has been a key forum for HBRC
and HBRIC Ltd to discuss the Tukituki Choices / Plan Change process and the development of
potential resource consent conditions for the Scheme associated with nutrient control and
management.
At the November 2012 meeting of the Pan Sector Group a preliminary Production Land Use consent
condition concept was tabled and discussed with general agreement expressed by the group in
relation to the proposed approach. This was further refined with a draft of the proposed Production
Land Use consent conditions tabled and discussed at the February 2013 meeting of the Pan Sector
Group. Again, the approach was generally ratified with a commitment made to circulate the relevant
draft conditions (Schedule Three in Part D of the RWSS resource consent application suite) at the
same time as the final draft documents are circulated to the EPA for its completeness check.
The Final Draft Schedule Three Conditions were circulated to the Pan Sector group members and
feedback received on some aspects from Irrigation New Zealand and Dairy NZ.
28.8 Key Farmer Reference Group
In January 2013, HBRIC established a Key Farmer Reference Group to discuss the proposed
Production Land Use consent conditions and potential incentives for existing irrigators to transition
to the Scheme if it is developed. An advanced draft of Schedule 3 of the proposed conditions was
circulated prior to the initial meeting of this Group held on 11 February 2013 where support for the
approach was expressed. At a follow up meeting on 25th February 2013 members of the Group
reconfirmed their support for the overall approach.
28.9 Hawke’s Bay District Health Board
Following completion of Part D- Proposed Conditions to Final Draft stage in mid-March 2013, Dr Nick
Jones of the Hawke’s Bay District Health Board provided HBRIC Ltd with comments, queries and
suggestions on a number of aspects of the draft conditions as they relate to public health issues -
principally regarding potential nitrate contamination of groundwater utilised for drinking water
supplies and Phormidium accumulation in the rivers used for contact recreation. Dr Jones also had
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suggestions as to how the approach taken to different contaminants resulting from land
intensification might be made more consistent and effective.
As a result of Dr Jones input a number of changes have been made to the proposed conditions in
Part D lodged with the EPA.
In relation to potential contamination of registered drinking water supplies, a plan was compiled
superimposing the location of the relevant water supplies on the model outputs discussed in Section
13 above. This figure below shows a low potential for contamination of registered drinking water
supplies.
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Dr Jones also queried the groundwater position in relation to Zone M. Although there are data of
existing groundwater in Zone M there is insufficient data to model groundwater in Zone M. HBRIC
Ltd’s investigations confirmed that the water supply for Otane is a shared supply with Waipawa
drawn from a bore well upstream of the proposed irrigation zone. Available databases did not
identify any public human drinking water supplies within or immediately down-gradient of the Zone
M area.
28.10 Outcomes of Consultation
The outcomes of consultation undertaken through the processes outlined above are summarised as
follows:
a) Input to a Scheme shaping through the early appointment and involvement of the
Leadership Group
b) Communication with and input from the Ruataniwha Stakeholder Group through 19
meetings held in Waipawa starting in May 2010, including agreement of the group to the
range and content of the environmental studies undertaken to support the feasibility
decision
c) Active involvement of the environmental groups on the Ruataniwha Stakeholder Group in
the development and prioritisation of elements of the five proposed Integrated Mitigation
and Offset projects (which is still on-going as at the date of lodgment of these applications)
d) Numerous meetings, presentations and discussions with a wide range of community groups
e) Regular briefings with landowners on whose properties Scheme infrastructure will be
located to assist with refining the primary distribution system and to form a basis for land
access agreements
f) Involvement of nominated members of the Ruataniwha Stakeholder Group in the Land Use
Intensification Working Party process
g) The convening of a Mana Whenua Working Party to provide a forum for Mana Whenua
represented by a number of groups to work with HBRIC Ltd representatives to develop
effective ways of addressing the recommendations of the various cultural impact
assessments which have been prepared for the Scheme.
h) Input from a Pan Sector group into the development of the proposed conditions for the
management of the Production Land Use element of the Scheme, as part of a wider brief
which also assisted HBRC with the approach to limit setting developed for Change 6
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i) Feedback from a Key Farmer Reference Group into the details of the proposed conditions for
the management of the Production Land Use element of the Scheme, as these were being
drafted
j) Liaison with the Hawke’s Bay District Health Board in the drafting of proposed conditions
associated with Public Health matters.