TYWYN COASTAL DEFENCE SCHEME ENVIRONMENTAL STATEMENT September 2009 Notice This report was produced by Atkins for Cyngor Gwynedd Council for the specific purpose of the Tywyn Coastal Defence Scheme Environmental Impact Assessment. This report may not be used by any person other than Cyngor Gwynedd Council without Cyngor Gwynedd Council’s express permission. In any event, Atkins accepts no liability for any costs, liabilities or losses arising as a result of the use of or reliance upon the contents of this report by any person other than Cyngor Gwynedd Council. Document History JOB NUMBER: 5081214 DOCUMENT REF: 5081214/67/DG/009 3 Final for client C McDougall/ M Boyd K Winnard R Morgan D Fenn September 2009 2 Draft for Atkins Internal Review C McDougall/ M Boyd K Winnard N Coulshed R Morgan September 2009 1 Draft for Atkins Internal Review C McDougall/ M Boyd K Winnard N Coulshed R Morgan August 2009 Revision Purpose Description Originated Checked Reviewed Authorised Date
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TYWYN COASTAL DEFENCE SCHEME …4.4 Geology and Coastal Processes 47 4.5 Flora and Fauna 60 4.6 Landscape and Visual Amenity 76 4.7 Water and Sediment Quality 98 4.8 Traffic and Transport
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TYWYN COASTAL DEFENCE SCHEME
ENVIRONMENTAL STATEMENT
September 2009
Notice
This report was produced by Atkins for Cyngor Gwynedd Council for the specific purpose of the Tywyn Coastal Defence Scheme Environmental Impact Assessment.
This report may not be used by any person other than Cyngor Gwynedd Council without Cyngor Gwynedd Council’s express permission. In any event, Atkins accepts no liability for any costs, liabilities or losses arising as a result of the use of or reliance upon the contents of this report by any person other than Cyngor Gwynedd Council.
Revision Purpose Description Originated Checked Reviewed Authorised Date
ENVIRONMENTAL STATEMENT
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Contents Section Page
Glossary of Terms and Acronyms iii
Non-Technical Summary 1
1. Introduction and Background 12
1.1 Introduction 12 1.2 Structure of Report 12 1.3 Assessment Requirements and Legal Considerations 13 1.4 Development Plan policy 14 1.5 Location and Site Description 15 1.6 Background to the Scheme 16 1.7 Scheme Aims and Objectives 18 1.8 Consideration of Alternatives 19
2. Proposed Scheme 22
2.1 Scheme Evolution 22 2.2 Design Details 22 2.3 Construction Methods 28 2.4 Operational Management and Monitoring 37
4.1 Introduction 45 4.2 Scope of the EIA 45 4.3 General Assessment Methodology 45 4.4 Geology and Coastal Processes 47 4.5 Flora and Fauna 60 4.6 Landscape and Visual Amenity 76 4.7 Water and Sediment Quality 98 4.8 Traffic and Transport 103 4.9 Recreation and Amenity 108 4.10 Noise 114 4.11 Air Quality 116 4.12 Historic Environment 117 4.13 Navigation 123 4.14 Commercial and Recreational Fisheries 126 4.15 In-Combination Impacts 128
5. Conclusions and Recommendations 129
5.1 Conclusions 129 5.2 Recommendations 129
6. Environmental Action Plan 136
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6.1 Introduction 136
7. References 150 List of Tables
Table 1.1 Relevant Shoreline Management Plan (SMP) Policies 14 Table 3.1 Consultees Present at Initial Scheme Presentation Meeting, 8 April 2009 40 Table 3.2 Summary of Consultation during Scoping and EIA Process 42 Table 4.1 Impact Assessment Criteria 47 Table 4.2 Wave Data 49 Table 4.3 Tidal and Extreme Water Levels for Aberdyfi 50 Table 4.4 Sea level rise predictions relative to 1990 base level 54 Table 4.6 Pen Llŷn a’r Sarnau SAC Interest Features 62 Table 4.7 Dyfi Estuary SPA Interest Features 62 Table 4.8 Craig yr Aderyn SPA Interest Features 63 Table 4.9 Cors Fochno and Dyfi Ramsar Site Interest Features 63 Table 4.10 Biotope Types 67 Table 4.11 Biotopes Adjacent to Outfalls 68 Table 4.12 Low Tide Bird Counts between the Afon Dysynni and Afon Dyfi 70 Table 4.13 Mitigation Measures to Reduce Sediment Release 73 Table 4.14 Footprint of Rock Structures and Beach Nourishment 74 Table 4.15 Sensitivity of Visual Receptors 92 Table 4.16 Potential Visual Impacts during Construction 94 Table 4.17 Potential Visual Impacts Post Construction 97 Table 4.18 Measures to Reduce Release of Sediments 101 Table 4.19 Traffic Count Data for locations along proposed delivery route to Tywyn 104 Table 4.20 Predicted increase in commercial vehicle numbers 106 Table 4.21 Predicted increase in commercial vehicle numbers 106 Table 4.22 Predicted increase in commercial vehicle numbers 107 Table 4.23 Predicted increase in commercial vehicle numbers 107 Table 4.24 Archaeological and Historic Interest Features within a 1km radius of Tywyn 119 Table 4.25 Summary of Effects within Study Area and Mitigation Measures 120 Table 4.26 Summary of Effects on Peat Deposits within Study Area and Mitigation Measures 121 Table 4.27 Summary of Effects Adjacent to Study Area and Mitigation Measures 122 Table 4.28 Summary of Effects and Mitigation Measures within Study Area 122 Table 4.29 Summary of Effects and Mitigation Measures within Study Area 123 Table 4.30 Occupancy Details for Aberdyfi Harbour 124 Table 4.31 Fishing Effort Data for the Llyn Area 126 Table 4.32 Fisheries Species Caught within the Llyn Area 127 Table 5.1 Summary of Environmental Impacts 130 Table 6.1 Draft Environmental Action Plan 137
Appendices
See separate document
ENVIRONMENTAL STATEMENT
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Glossary of Terms and Acronyms
Term Meaning / Definition
Accreting Occurrence of ‘accretion’ (see below)
Accretion The accumulation of sediments from any source, representing an excess of deposition over erosion
AOD Above Ordnance Datum - standard land height reference level used by Ordnance Survey based on mean sea level at Newlyn, Cornwall
Aeolian Processes
Processes pertaining to the activity of the winds and more specifically, to the winds' ability to shape the surface of the Earth
Appropriate Assessment Assessment of the impacts of a proposal upon European designated sites
BAP Biodiversity Action Plan – strategic framework for dealing with biodiversity conservation
Beach Nourishment The importation of material to add to existing natural sediment on a beach
Biotope An area of uniform environmental conditions providing a living place for a specific assemblage of plants and animals
Blue Flag Award A voluntary quality award for beaches and marinas adhering to criteria covering environmental education and information, water quality, environmental management and safety and services
Breakwater An offshore structure, usually constructed of rock designed to dissipate wave energy and provide protection to the beach or harbour in its lee.
BTO British Trust for Ornithology
Bull Head Rail A type of railway track. Not generally used on mainline track anymore. As a strong, hardwearing and generally non-corrosive metal, it is sometimes seen as part of the structure of sea defences.
Bunded Area Area surrounded by a bund designed to retain fluids in the event of a spillage or leakage
CCW Countryside Council for Wales – the statutory nature conservation body in Wales
CD Chart Datum - the theoretical level of water in any tidal area during the lowest astronomical tide (LAT)
CDM Construction Design Management
CEC Crown Estate Commission – organisation responsible for managing ‘Crown Land’ (see below)
CEMP Construction Environment Management Plan
CES Civil Engineering Solutions
CGC Cyngor Gwynedd Council
Coast Protection A scheme designed to protect the coastline from erosion or encroachment by the sea
Coastal Defence Protection of the coast against erosion and flooding
Coastal Processes The action of natural forces on the shoreline and nearshore area
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Competent Authorities Person or organization that has the legally delegated or invested authority, capacity, or power to perform a designated function.
CPA Coast Protection Act 1949
CRoW Countryside and Rights of Way Act 2000
Crown Land Land owned by the monarchy
Defra Department of Environment, Food and Rural Affairs
DoE Department of Environment
Downdrift In the direction of the net longshore transport of beach material
d50 The median particle size of sediment (in a sample on in an area)
EAP Environmental Action Plan
EAW Environment Agency Wales
EIA Environmental Impact Assessment - the process of considering the effect of a proposal on the environment
EMS European Marine Site - refers to those marine areas of both SACs and SPAs, which are protected under the EC Habitats and Birds Directives
Erosion The detachment of material from the earth’s surface by the agents of water, wind and ice
ES Environmental Statement - the report on the EIA process
EU European Union
EC Bathing Water Directive (76/160/EEC)
Sets limits for chemical, physical and microbial parameters to ensure good bathing water quality in coastal and inland waters
EU Birds Directive (79/409/EEC)
Aims to protect all European wild birds and the habitats of listed species, in particular through the designation of Special Protection Areas (SPAs)
EU Convergence Funding Grants available to aid the regeneration of an area and to help the region’s transformation into a sustainable and competitive economy by investing in the knowledge economy and helping new and existing businesses to grow
EU Habitats Directive (92/43/EEC)
Aims to protect species and habitats which are considered to be of European interest and are listed in the Directive’s Annexes
European designated sites Sites designated under the EU Habitats and Birds Directives
Faecal Coliforms Group of bacteria, including the genera that originate in faeces as well as those not of faecal origin. The presence of faecal coliforms in aquatic environments may indicate that the water has been contaminated with the faecal material of man or other animals
Fauna Animals
FCDPAG Flood and Coastal Defence Project Appraisal Guidance
FEPA Food and Environment Protection Act 1985
Fines Particles of diameter less than 0.063mm (silt and clay)
Fishtail Breakwater / Fishtail Groyne
“Y” shaped rock structure that combines the benefits of both a breakwater and a groyne. The shape resembles a fishtail, hence the name
Flora Plants
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Foreshore The section of the coastline between the low and high water mark
FRA Flood Risk Assessment
Frontage The extent of land abutting the beach
FSC Forest Stewardship Council - independent, non-governmental, not-for-profit organisation established to promote the responsible management of the world’s forests
GAT Gwynedd Archaeological Trust
Geotextile Layer Synthetic material commonly placed beneath rock structures prior to construction to reduce future subsidence through the movement of sediment up through the structure
Glacial Till A mixture of fine and coarse rock debris deposited by a glacier
Greenheart Wood Valuable South American hardwood timber tree of the laurel family. The timber is both strong and dense and is commonly used for marine applications, such as pilings for wharves. Its weight makes it largely unfit for other purposes
Groyne A low wall built out from the coast into the sea, to reduce longshore drift
Groyne Field Series of groynes acting together to protect a section of beach.
HAT Highest Astronomical Tide – the highest levels which can be predicted to occur under average meteorological conditions and under any combination of astronomical conditions
Hinterland The land behind the coast
Hold the Line The process of retaining the existing line of the shore / river bank by carrying out maintenance, repairs and replacement of defences, as necessary
Holocene The geological epoch which began approximately 11,700 years ago and according to traditional geological thinking continues today
HRA Habitats Regulations Assessment - the name by which ‘Appropriate Assessment’ is now generally referred (see above)
Intertidal Zone or Foreshore The area between Lowest Astronomical Tide and Highest Astronomical Tide
Longshore Transport Movement of beach sediment parallel to the shore, within the surf zone. Also called Longshore Drift
LAT Lowest Astronomical Tide - the lowest levels which can be predicted to occur under average meteorological conditions and under any combination of astronomical conditions
LVA Landscape and Visual Assessment - the process of assessing the impact of a scheme on the existing visual landscape
Managed Retreat The process of moving the line of the shore / river bank back from its current position
MCCIP Marine Climate Change Impacts Partnership
MDC Meirionnydd District Council (local authority prior to the formation of CGC)
MHW Mean High Water - highest average level water reaches on an outgoing tide
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MHWS Mean High Water Springs – the average level of high water during the spring tides
MLW Mean Low Water – lowest average level water reaches on an outgoing tide
MLWS Mean Low Water Springs – the average level of low water during the spring tides
MNCR Marine Nature Conservation Review
Multi Criteria Analysis A decision-making tool developed for complex problems.
Natura 2000 The network of protected sites designated under the EU Birds and Habitats Directives
NNR National Nature Reserve
NSO National Statistics Online
OPSI Office of Public Sector Information
OS Ordnance Survey
Overtopping Passing of water over the top of a structure as a result of wave action, seawater spray or the still water level exceeding the crest level
PAR Project Appraisal Report
Pers. Comm. Personal Communication
PPG Planning Policy Guidance
Piling A column of wood, steel or concrete that is driven into the ground to provide support for a structure
PPS Planning Policy Statement
Ramsar Convention Convention on Wetlands of International Importance, is an intergovernmental treaty that provides the framework for national action and international cooperation for the conservation and wise use of wetlands and their resources
Resilience Actions Actions taken to improve the ability of a community to cope with an event, risk or uncertainty. In this case, to better cope with the consequences of flooding, erosion and climate change.
Revetment Shore protection structure constructed of rock laid at a determined slope angle. Voids within the structure dissipate wave energy
Rock Armour Large rocks placed in order to provide a protective layer
Rock Berm A narrow ledge or mound of rock
SAC Special Area of Conservation – area designated under the Habitats Directive and provide rare and vulnerable animals, plants and habitats with increased protection and management
Sand Particles/grains of diameter between 0.063mm and 2mm
Sea Level Rise The long term upward trend in mean sea level resulting from a combination of local or regional geological movements (rise or fall of land) and global climate change
Sediment Cell A length of coastline and its associated near shore area within which the movement of coarse sediment (sand and shingle) is largely self contained. Interruptions to the movement of sand and shingle within one
ENVIRONMENTAL STATEMENT
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cell should not affect beaches in an adjacent sediment cell
Sheet Piling A type of retaining wall achieved by driving interlocking sheets of steel into the ground
Shingle Stone diameter between 2mm and 75mm, also called gravel.
SI Statutory Instrument – a type of secondary legislation (law)
Slipway A sloping surface, leading down to the shore from which ships/boats are launched
SMP1 Shoreline Management Plan - sets the policy for coastal management (1st
Generation) – provides a large-scale assessment of the risks associated with coastal processes and presents a long term policy framework to reduce these risks to people and the developed, historic and natural environment in a sustainable manner
SMP2 Shoreline Management Plan Review - sets the policy for coastal management (2
nd Generation) – see ‘SMP1’ above
SNP Snowdonia National Park
SNPA Snowdonia National Park Authority
SPA Special Protection Area – area designated under the Birds Directive to help protect and manage areas which are important for rare and vulnerable birds because they use them for breeding, feeding, wintering or migration
Specific Asset Assessment An evaluation of the sea defences in place in a particular area
SSSI Site of Special Scientific Interest – an area that has been notified as being of biological or geological importance under the Wildlife and Countryside Act (WCA) 1981
Swash Aligned Land orientated parallel to prevailing waves
Terminal Groyne The groyne at the end of a series of groynes. This will mark the end of groyne field in the downdrift direction
TIA Traffic Impact Assessment - a process of determining the effect of a proposal on the existing volume of traffic
Toe The relatively small mound usually constructed of rock armour to support an armour layer, buried under the existing ground level
Turbary A piece of peat from which turf can be cut for fuel
UDP Unitary Development Plan – the Local Authority adopted plan that sets out priorities and proposals for development and any conditions that may be need to be met
UKCIP United Kingdom Climate Impacts Programme
UKCP09 United Kingdom Climate Projections 2009
UNESCO United Nations Educational, Scientific and Cultural Organization
UKHO United Kingdom Hydrographic Office
WAG Welsh Assembly Government
WCA Wildlife and Countryside Act 1981
Walings Horizontal support used to maintain intergity of a structure (pronounced ‘wailings’). Timber walings provide support to timber piles of a groyne
ENVIRONMENTAL STATEMENT
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WEFO Welsh European Funding Office
ZVI Zone of Visual Influence - geographical extent to which the development proposals are visible from surrounding areas
ENVIRONMENTAL STATEMENT
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Non-Technical Summary
Introduction
Cyngor Gwynedd Council (CGC) proposes to undertake a coastal defence scheme in Tywyn to
improve the defences along the seafront. CGC commissioned Atkins to produce this
Environmental Statement (ES) to support the planning application and other, marine consents,
needed in order to progress the scheme.
Background to the Scheme
Tywyn, is a small seaside town on the west coast of Wales in Cardigan Bay between the Afon
Dysynni (to the North) and the Afon Dyfi (to the South), within the county of Gwynedd (Figure 1 in
Appendix A). It has a population of 3,266 (NSO, 2009).
The Tywyn coastal frontage has suffered several significant damaging events, experiencing storm
damage in nearly every decade since the 1930s and emergency works have been required on
numerous occasions. Over the last 100 years, the height and width of the beach has also
receded. Over this time, the beach level at Warwick Place has dropped by 3m.
The installation of timber groynes in the 1970s reduced the rate at which the beach receded but
has not reversed it, and overall beach recession is expected to continue. In the last 10 years the
rate of beach lowering at certain locations along the frontage has been greater than the long-term
average, leading to overtopping of the current defences and flooding during storm events. The
erosion of the beach, combined with the deterioration of the groynes has contributed to the sea
wall being undermined, particularly at Bryn-y-mor.
The land behind the sea wall is relatively flat, meaning that overtopping sea water is able to flow
inland relatively freely. Flooding is most prevalent at the Southern end of the promenade at
Warwick Place.
The United Kingdom Climate Impacts Programme (UKCIP) and Marine Climate Change Impacts
Partnership (MCCIP) predict an increase in storminess and wave height in coming years.
Continued recession of the beach is increasing the risk of damage to the sea wall and from future
flooding events, particularly in the light of climate change impacts. Whilst it has been possible to
repair the sea walls and replenish the beaches following storm events to date, this approach is
expected to become unsustainable in the context of sea level rise and increased storminess as a
result of climate change.
In December 2004, the Welsh Assembly Government (WAG) confirmed that a scheme could be
eligible for funding if it were to meet the required technical, environmental and economic criteria.
In 2009, WAG confirmed that CGC had been successful in their bid for EU Convergence Funding
for a coastal defence scheme.
Assessment Requirements and Legal Considerations
The proposed scheme (the 2009 Scheme) requires planning permission from CGC under the
Town and Country Planning Act 1999 (TCPA). It also requires consent under the Food and
Environment Protection Act 1985 (FEPA), and Coast Protection Act 1949 (CPA), applications for
which are administered by the Marine and Fisheries Agency (MFA).
The Town and Country Planning (Environmental Impact Assessment) Regulations 1999 (SI 293)
and the Marine Works (Environmental Impact Assessment) Regulations 2007 (SI 1518) list
projects for which an Environmental Impact Assessment (EIA) is required. The proposed scheme
ENVIRONMENTAL STATEMENT
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falls within the lists of projects for which an EIA is discretionary. Given the scheme’s location
adjacent to sites designated under the European Habitats Directive, CGC and the Countryside
Council for Wales (CCW) considered an EIA to be needed to assess the potential for
environmental impacts.
Planning permission and marine consents for a similar, larger scheme (the 2005 Scheme) were
granted in 2005. An Environmental Impact Assessment (EIA) was undertaken by ABPmer for
these consent applications.
This document is the Environmental Statement (ES), prepared as part of the EIA process, in
accordance with the Marine Works (EIA) Regulations and with the Town and Country Planning
(EIA) Regulations to accompany the planning application and FEPA/CPA application for the 2009
Scheme. Section 1 of the ES contains more detail on these legislative requirements.
The Habitats and Birds Directives require ‘competent authorities’ to undertake an ‘appropriate
assessment’ of plans, projects and strategies that may have a significant effect on EU protected
sites. This ‘appropriate assessment’ process is known as a Habitats Regulations Assessment
(HRA). Information to inform a Habitat Regulations Assessment (HRA) has been included within
this report, due to the proposed scheme’s proximity to EU protected sites. Section 4 and
Appendix E of the ES contain information to support a HRA.
There are a number of potentially sensitive areas adjacent to and near to the proposed Scheme,
including:
• Pen Llŷn a’r Sarnau Special Area of Conservation (SAC) (also referred to as the Pen
Llŷn a’r Sarnau European Marine Site1)
• Craig yr Aderyn Special Protection Area (SPA)
• Dyfi Estuary SPA (also referred to as the Dyfi Estuary European Marine Site)
• Cors Fochno and Dyfi Ramsar site
• Biosffer Dyfi Biosphere
• Broadwater Site of Special Scientific Interest (SSSI)
• Dyfi SSSI
• Dyfi National Nature Reserve (NNR)
Tywyn is located very near to the Snowdonia National Park and, while not within the Park itself,
the Scheme could potentially impact on views and the landscape. More detail on the location and
site description is in Section 1.4 of the ES.
The ES produced in 2005 to accompany the planning application was reviewed to inform the
scope of this ES. Views on the scope of this ES were sought from consultees, including the CCW,
Environment Agency Wales, (EAW), CGC, Snowdonia National Park Authority (SNPA) and
Gwynedd Archaeological Trust (GAT) (see Section 3 of the ES).
Scheme Aims and Objectives
The scheme aims to reduce the amount of water overtopping the seawall at Warwick Place and
improve or maintain the amenity value of the beach, which is important to the local community,
visitors and tourists. The scheme has a number of inter-connected aims relating to both the
1 Where a European site is located below the level of the highest astronomical tide (HAT) they are described
as European Marines Sites.
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management of impacts from coastal flooding and erosion and the amenity value of the beach
and promenade:
• Reduce the amount of water overtopping the seawall at Warwick Place
• Maintain access to the beach
• Maintain or improve the amenity value of the beach
• Ensure that the scheme is safe and suitable for public access
• Ensure that the scheme is environmentally acceptable and does not unduly impact on
adjacent areas, designated conservation sites, Biodiversity Action Plan (BAP) habitats
and species and landscape
• Ensure that the scheme is economically viable
• Reduce the rate of decrease in beach level
• Build in flexibility / adaptability to enable alterations to be made in response to New
Approaches and the developing Shoreline Management Plan Review (SMP2)
More detail on the 2009 Scheme aims and objectives is in Section 1.6 of the ES.
Consideration of Alternatives
Over the last 15 years, several schemes have been proposed and developed, although none have
been constructed. A non-technical summary of the alternatives is provided below. For more
detailed information, see Section 1.7 of the ES.
Do Nothing
Over time the defences will continue to fail and lead to increased erosion and overtopping. This
would result in on-going costs to CGC to clear overtopped shingle from the car parks and roads,
and provision of sandbags to local residents and businesses affected by overtopping. In addition,
the timber groynes, slipways and access steps would continue to deteriorate, making access to
the beach more difficult and potentially becoming a hazard to beach users.
As sea levels rise, the coastline will try to retreat landward and the possibility of the sea breaching
the natural defences to the North and South of Tywyn, to the low lying land behind will increase.
Scheme 1 (Fish Tail Groynes)
This scheme comprised a series of seven fishtail breakwaters with a mix of sand and
shingle/cobble being used for beach nourishment. The scheme was designed to keep the beach
at a relatively high level. During storms the beach would protect the sea wall by limiting the size of
waves and controlling the amount of overtopping. Further nourishment of the beach at suitable
intervals throughout the design life would have been required. The scheme was to be a
partnership with Meirionnydd District Council (MDC), EAW and Railtrack contributing towards the
cost of works to their frontages.
This approach was not approved by the Welsh Office, which raised technical and financial
concerns with respect to the design and cost-benefit analysis. This resulted in the scheme not
being pursued (ABPmer, 2005).
Scheme 2 (Rock Revetment)
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A second opinion of coastal defence requirements was sought by the Welsh Office from HR
Wallingford in 1997 and the resultant report was published in 1999. This scheme proposed the
use of rock-armour revetments (retaining structures built of large rocks) and rock groynes to
protect the existing walls and reduce the amount of wave overtopping during storms. This
proposal would not have controlled the beach levels and over the longer term, it was expected
that the structure would have needed to be extended (ABPmer, 2005).
This option was tested with models used by CGC and was presented at a public exhibition in
August 2001. It resulted in considerable local opposition because the stepped revetment along
the sea wall of the existing defences, which are seen as an important amenity feature by the local
community would be lost.
Scheme 3 (Headland Breakwater 2005 Scheme)
CGC contracted ABPmer as independent consultants to review the issues, identify a design
solution and help agree a way forward with the local community. The Tywyn Coastal Protection
Review (ABPmer, 2004a) examined the previous schemes, as well as the objectives of the coastal
defence strategy for Tywyn. The 2005 Scheme was proposed to meet both the flood and coastal
defence requirements as well the needs of the local community. The 2005 Scheme was well
received during public consultations and presentations and was supported by CGC.
All the applications required for constructing the scheme were submitted and granted, however,
funding was not able to be secured.
Current Scheme (Headland Breakwater 2009 Scheme)
In the summer of 2008, Atkins was commissioned by CGC to review and refine the 2005 Scheme
proposed by ABPmer and assist CGC in their application for EU Convergence Funding. CGC
were successful in their funding application and Atkins was commissioned to take forward the
design. By this time, the various licenses had lapsed. Refinement to the shape and size of some
rock structures also meant that CGC Planning Department considered that a new planning
application was also needed.
This Environmental Statement (ES) is designed to present information on the likely environmental
impacts of the refined scheme (hereafter referred to as ‘the 2009 Scheme’), assess their
significance and set out mitigation measures to reduce or avoid the impacts. It is also designed to
support the planning permission and applications for marine consents and provide information to
make an assessment of the impacts of the scheme under the EU Habitats Regulations.
The 2009 Scheme
The scheme comprises a number of elements, which when taken together aim to meet the
objectives of the whole scheme:
1. Construction of a rock armour breakwater at Warwick Place (Warwick Place Breakwater) –
built of granite rock of 3 – 12 tonnes each. The breakwater will be approx. 150m long at its
base, 66m long along the crest. It will be between 41m and 63m wide. At its highest, it will
be 4m AOD (approx. 1.5m above Mean High Water Springs (MHWS)). At Mean High Water
(MHW), when the tide is in only the upper 1.5m of the breakwater will be exposed. At MLW,
when the tide is out, the breakwater will be completely exposed.
2. Construction of a South Terminal Rock Groyne near Neptune Road - built of granite rock of
6 – 10 tonnes each. The South Terminal Rock Groyne will be approximately 12m wide and
50m long. At its highest point (where it is connected to the seawall) it will be 4m AOD and
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will slope downwards towards the beach. At MHW, the majority of the groyne will be
submerged, while at MLW, the entire structure will be exposed.
3. Construction of a rock groyne at Pier Road (Pier Road Rock Groyne) - built of granite rock of
6 – 10 tonnes each. The Pier Road Rock Groyne will be an L-shaped structure extending
approximately 27m from the sea wall before ‘dog-legging’ slightly and extending a further
21m. It will be connected to the seawall at its landward end by a concrete viewing platform.
It will be approx. 20m wide.
4. Construction of a rock revetment at Bryn-y-mor, between groyne 28 and groyne 34 (Bryn-y-
mor Rock Revetment) - built of granite rock of 3 – 6 tonnes each. The Bryn-y-mor Rock
Revetment will stretch approx. 270m along the beach front at Bryn-y-mor. It will be at a
maximum, 5.8m wide at its base. It will be partly submerged at MHW and completely
exposed at MLW.
5. Beach nourishment behind the Warwick Place breakwater – approx. 16,500m3 of material
will be placed on the beach behind the Warwick Place Breakwater. The material used will
be of a similar size and colour to the existing beach material.
6. Alterations to all 34 timber groynes through either removal (7 groynes in total – in the areas
where new rock structures are being built or beach nourishment is taking place) or
replacement (27 groynes in total).
7. Improvement of rock revetment by the Warwick Place slipway (between the slipway and
groyne 06) – to improve the current 70m blockstone revetment, which is in a state of
disrepair.
8. Reconstruction of concrete steps along the length of the bottom of the promenade to the
same specifications / dimensions as the original steps.
9. Reconstruction of Warwick Place slipway to the same specifications / dimensions as the
original slipway.
10. Minor refurbishment of the promenade including construction of a Coastal Information
Centre (CIC – this will be subject to a separate planning application in the future. Impacts
are not considered in this ES)
11. Refurbishment or repair of beach access steps at groyne numbers 02, 19, 21, 23, 25 and 28
and slipways at groyne numbers 02 and 28 to the same specifications / dimensions as
original.
Drawings illustrating the design elements are contained in Figures 3 – 8 in Appendix A of the
ES. More detail on the design details are in Section 2.2 of the ES. A non-technical summary of
the construction methodology and operational management of the 2009 Scheme, post
construction is provided below. For more detailed information, see Sections 2.3 and 2.4 of the
ES.
Construction methodology
Construction is scheduled to commence in November 2009 and be completed by the end of
March 2011; a duration of 18 months. Two site compounds will be used – one on CGC land
behind the area where the Bryn-y-mor Rock Revetment will be constructed; the other in the car
park adjacent to the Warwick Place slipway.
Construction of the rock structures will require some excavation of the beach, up to a depth 1.5m.
A geofabric membrane will be placed on the bottom of the excavated area. Rocks will be
individually placed on top of the geofabric by excavators.
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Materials may be delivered to Tywyn by sea or road. The ES considers the potential impacts
associated with the possibility of two possible delivery options:
• Delivery option A – delivery of large rock by sea. Smaller rock (approx. 1/3 of total rock
required) and all other construction materials (including timber, plant, beach nourishment
and labour) would be delivered by road.
• Delivery option B – delivery of all materials by road.
Operational Management and Monitoring
The new structures will require some ongoing maintenance, structural checks and upkeep. Beach
nourishment is not expected to be needed again within 10 years of completion of the scheme.
There will also be a need to carry out monitoring of the beach and the beach nourishment area.
This will be form part of CGC’s established monitoring programme, which has been ongoing for
the last 15 years.
Impact Assessment
A number of consultations were carried out with statutory and non-statutory organisations for
scoping and during the preparation of his ES from February 2009 onwards. CGC has also
consulted with the Tywyn Town Council and held a public exhibition of the scheme in September
2009.
Scope of the ES
The scope of the impact assessment for this ES has been determined through assessing the
scope of the EIA carried out in 2005 by ABPmer for the 2005 Scheme, which successfully
provided adequate assessment for the scheme to be approved for planning permission and
marine consents and consulting with key environmental stakeholders (including CGC, CCW and
EAW).
The following issues have been included in the scope of the impact assessment and this ES:
• Geology and Coastal Processes – including sediment transport, shoreline evolution,
impacts on adjacent stretches of coast and coastal defences
• Flora and Fauna – including impacts on European designated sites and species
• Landscape and Visual Amenity
• Water and Sediment Quality
• Traffic and Transport – including impacts of Delivery Option A and Delivery Option B
• Recreation and Amenity
• Noise
• Air Quality
• Historic Environment
• Navigation
• Fisheries
• Inter-relationship between the above and in-combination with other projects
• Interaction with other proposals in the area
ENVIRONMENTAL STATEMENT
Tywyn Coastal Defence Scheme
7
An assessment of the construction and post construction impacts of the proposed development on
each of the issues listed above has been carried out by considering the impacts against baseline
conditions. Impacts within the scheme area and outside the scheme area have been assessed.
The scheme area is defined as the area of foreshore between groyne 01 and groyne 34 (Figure
2, Appendix A of the ES). Impacts have been defined as major, moderate, minor or neutral
and may be beneficial (positive) or adverse (negative) and temporary or permanent.
The assessment of impacts has been carried out using published data, the results of surveys,
professional judgement and numerical modelling, where appropriate. Where adverse impacts
have been identified, mitigation measures are proposed to minimise or compensate for these
impacts. Mitigation will seek to reduce the impact to an acceptable standard for that specific
receptor, or eliminate the impact entirely. More detail on the impact assessment scope and
methodology can be found in Sections 4.2 and 4.3 of the ES.
A non-technical summary of the impact assessment is provided below. For more detail, see
Sections 4.4 – 4.15 of the ES.
Geology and Coastal Processes
Within the Site
During construction the works will have a neutral impact on sediment transport. Once built, the
structures will have a beneficial impact on the flooding and overtopping issues in Tywyn, but are
also likely to have a minor adverse impact on coastal processes within the site area in the short
term, as the coastal process systems adjust to the new structures. However, there will be a
minor beneficial effect on the sediment budget, due to the beach nourishment. The impact on
sediment movement along the shore, the dune system and the SAC is considered to be neutral.
In the longer term (20 – 50 years) the 2009 Scheme will have a neutral impact on coastal
processes within the site.
Outside the Site
The ability of the 2009 Scheme to alter the coastal processes outside of the site beyond those
seen now or in the future is minimal and the impact of the scheme to either the North or the South
of the site, including any impacts on the Dyfi geological SSSI is likely to be neutral.
It is considered that the 2009 Scheme will have a stabilising effect on the beach at Tywyn but will
not alter the behaviour of the overall section of coastline. The increases to the sediment budget
overall will be minor beneficial.
It is considered likely that the 2009 Scheme will have a neutral impact outside of the site in
comparison to the existing situation in both the short term (0-20 years) and the medium term (20-
50 years).
Flora and Fauna (plants and animals, including habitats)
During construction, impacts on flora and fauna in the area immediately behind the proposed
works will be neutral. There is the potential for construction work to affect plants and animals
living on/in the beach (the intertidal area), by the movement of vehicles, plant and the storage of
materials on the beach. It is important to avoid the patches of Sabellaria alveolata reef on the
beach. Impacts can be reduced by minimising the area of beach used by vehicles and materials
and agreeing site traffic routes / no-go areas prior to works commencing. With these actions,
habitat/species loss impacts are considered to be minor adverse.
ENVIRONMENTAL STATEMENT
Tywyn Coastal Defence Scheme
8
The removal of timber groynes will cause the permanent loss of small areas of Sabellaria
alveolata reef but this will be countered by the construction of new timber groynes and of the rock
structures, providing new areas for species to colonise. Impacts are considered to be minor
adverse (to Sabellaria reefs) but minor beneficial impact for other intertidal flora and fauna. The
beach nourishment is considered to have a neutral impact on intertidal flora and fauna.
None of the structures will be built within the Pen Llŷn a’r Sarnau SAC. The contractors will,
where possible, construct the breakwater from its landward side, working backwards up the
beach. Should the contractor need access to the seaward side, this is likely to involve movement
within a maximum 10m x 50m wide strip to manoeuvre machinery. No SAC features have been
identified in this area and the impacts of physical damage to SAC features are determined to be
minor adverse.
All the construction work will be confined to the Tywyn frontage (between groynes 01 and 34) and
therefore there will be no impacts (neutral) on adjacent intertidal flora and fauna.
Impacts on marine species and habitats caused by sediment released or underwater noise /
vibration during construction are considered to be neutral or minor adverse. Post construction,
there are no impacts on marine flora or fauna (neutral).
Impacts on birds caused by disturbance during construction are considered to be minor adverse
or neutral, but time limited to the construction period. Following construction, the rock structures
could provide minor beneficial impacts for birds by providing roosting areas and potential extra
food source areas.
Delivery Option A – delivery of large rock by sea - will not result in any additional impacts to those
set out above.
Delivery Option B – delivery of all materials by road - will require the creation of a stockpile of rock
on the beach and additional movement of site traffic across the beach to transport rock from the
site compounds to the areas where rock structures are being built, creating moderate adverse
impacts on intertidal habitats and species. The contractor will be instructed to avoid areas of
Sabellaria alveolata reef. The use of protective mats may be required in some areas. The need
(or otherwise) for such measures should be agreed by the contractor with CCW / CGC prior to
selecting the routes across the beach for site traffic. The impact on losses of habitats and species
can, therefore, be reduced to minor adverse.
Landscape and Visual Amenity
During construction, the impacts to landscape and visual amenity are considered to range from
moderate to substantial adverse (depending on the location along the shorefront and the
proximity to construction works), due to the presence of site compounds, stored materials and site
traffic / delivery vehicles / vessels. Mitigation measures during construction are limited, as
screening is unlikely to mitigate these impacts, due to the low lying nature of the landscape.
These impacts are, however, time limited to the duration of the works.
Following construction, the impacts on landscape and visual amenity range from slight to
moderate beneficial. Negative impacts (such as the construction of large rock structures) are
balanced by shorter timber groynes, improved access and repairs to currently dilapidated
structures. Impacts could be further reduced by additional regeneration of the promenade to
further improve the character and visual amenity of the area.
Water and Sediment Quality
Any sediment released into the sea during construction is likely to be in small quantities. Impacts
on water quality in terms of suspended sediments are considered to be minor adverse as is the
ENVIRONMENTAL STATEMENT
Tywyn Coastal Defence Scheme
9
potential impact on water quality arising from the use of machinery / vehicles. Other impacts on
water quality during construction, including to Bathing Water quality are considered to be neutral.
Post construction, impacts are considered to be neutral.
Traffic and Transport
The impact on traffic and transport is associated with the delivery of materials by road and the
effects this has on the local road network, congestion and other road users. Delivery Option A
(delivery of large rock by sea) includes the delivery of some material by road (approx. 1/3 total
rock required and all other materials. Delivery Option B would involve all construction materials
arriving by road. Both Delivery Option A and Delivery Option B would have moderate adverse
impacts on traffic and transport. Delivery Option B would require additional mitigation measures
to reduce impacts.
Post construction, impacts on traffic and transport are considered to be minor beneficial due to
the reduced impacts of flooding and overtopping to the road / footpaths along the Tywyn frontage.
Recreation and Amenity
The presence of construction vehicles, site compounds and general construction activities will
create minor adverse impacts for promenade users, to parking facilities and to visitors to the
beachfront area.
Construction activities temporarily reducing the number of access points to / from the beach will
have an adverse impact on beach users. This is considered to be minor adverse under Delivery
Option A but moderate adverse under Delivery Option B.
Water and slipway users will, however, experience minor adverse impacts under Delivery Option
A, due to the presence of delivery vessels in the water for short periods of time. Using Delivery
Option B, water users would experience a neutral impact, but slipway users would experience
moderate adverse impacts due to the increased likelihood of either the Warwick Place and / or
the Pier Road slipways being unavailable for public use.
Post construction, the new structures will create a minor adverse impact to beach users by their
presence on the beach, however, the replacement of the old timber groynes with new, shorter
timber groynes will be of minor to moderate beneficial impact, by improving access along the
shore. Other access improvements and refurbishments would create a moderate beneficial
impact for beach users.
Parking and promenade users will experience minor to moderate beneficial impacts post-
construction, due to improved facilities and reduced risk of damage caused by wave overtopping.
Sea users will in general be unaffected (neutral impact), apart from a minor adverse impact due
to the presence of the new rock structures. Navigational markers and warning signs will be
erected on and around the new structures to warn all beach and sea users of the potential risks of
collision or from climbing on the structures.
Noise
Delivery Option A – delivery of large rock by sea – will generate noise, some of which will be
during night time hours (7pm – 7am) when rock is unloaded from delivery barges. These and
other noise impacts (general construction noise, site vehicles, etc.) are considered to be
moderate adverse and time limited. There will be no noise impacts post construction (neutral).
ENVIRONMENTAL STATEMENT
Tywyn Coastal Defence Scheme
10
Delivery Option B – delivery of all materials by road – will generate greater amounts of noise from
the additional delivery vehicles, tipping of rock during unloading and greater site traffic movements
required by this method over the majority of the construction period. These are considered to
create major adverse impacts. These impacts will be time limited to the construction period.
There will be no noise impacts post construction (neutral).
Air Quality
Delivery Option A – delivery of large rock by sea – will have a neutral impact on air quality.
Delivery Option B – delivery of all materials by road – will have a minor adverse impact on air
quality, due to the number of HGVs required to deliver materials and the need for more vehicle
movements on site creating more vehicle emissions.
Historic Environment
No significant features of heritage interest that could be directly affected by the scheme were
identified in the study area. Heavy vehicle / plant movement and repairs to the pro historic
promenade are considered to be minor adverse and a suitable construction methodology should
be agreed with Gwynedd Archaeological Trust (GAT) to limit impacts. Construction activities may
also damage ancient peat beds, if they are found during the excavation works. All ground
investigations undertaken so far have found no peat deposits within the 2009 Scheme area.
There are no impacts post construction (neutral).
Navigation
Delivery Option A – delivery of large rock by sea – would require vessel management measures
and the placement of appropriate shoreline signage during the movement of rock delivery vessels.
This is considered to have a minor adverse impact on navigation immediately offshore of Tywyn.
Impacts further South in the vicinity of the Aberydyfi Harbour and on lifeboats are considered
neutral.
Delivery Option B – delivery of all materials by road – will have no impact on navigation (neutral).
Post construction the 2009 Scheme is considered to be minor beneficial due to the improved
shelter offered by the scheme to the slipways.
Fisheries
The 2009 Scheme is not considered to have any impacts (neutral) on commercial or recreational
fisheries, other than those already outlined under other sections (e.g. navigation, slipway users)
either during or after construction.
Inter-relationship between the above and in-combination with other projects
There are no other coastal protection schemes known to be taking place along the Tywyn
Frontage or the adjacent coastline which could contribute to and increase the magnitude of the
impacts described above.
A coast protection and improvement scheme is planned on the Ceredigion coast at Borth, to the
South of the Dyfi estuary. The Dyfi estuary is a natural break in the coastal processes, preventing
the transport of sediment from North of the Dyfi Southwards, or vice versa and in-combination
impacts are considered to be neutral.
ENVIRONMENTAL STATEMENT
Tywyn Coastal Defence Scheme
11
The combined impacts of the 2009 Scheme are not considered to be significant if the mitigation
actions set out in this ES are followed. Delivery Option B would result in slightly greater combined
impacts, given the additional numbers of HGVs, increased site vehicle movements needed and
the increased noise generated by tipping rock when unloading vehicles. These impacts are,
however, time limited to the construction period (18 months duration). The combined impacts of
the 2009 Scheme post-construction are not considered to be significant.
Conclusions and Recommendations
Adverse and beneficial impacts on the environment have been identified. Major / substantial
adverse effects on the environment have been identified during the construction period (approx.
November 2009 – March 2011). These are mainly landscape and visual amenity impacts and will
not continue post-construction. Delivery Option B (delivery of all materials by road) would result in
major noise impacts during the construction period (compared with moderate noise impacts
associated with Delivery Option A).
Moderate or minor adverse impacts of the 2009 Scheme are also generally time-limited to the
construction period.
Only minor post-construction adverse impacts have been identified and these are offset by other
beneficial impacts e.g. loss of substrate through removal of old timber groynes is offset by the
creation of substrate by new timber groynes and rock structures. Overall, the Scheme is
considered to have a neutral or minor beneficial impact if the mitigation measures set out in this
ES are followed.
Information to inform a HRA has been included within this ES due to the proposed scheme’s
proximity to European protected sites. This concludes that, if mitigation measures are
implemented as set out, the impact on protected sites is neutral.
A copy of the draft Environmental Action Plan (EAP) that accompanied constructor tender
documents has been included in the ES (Section 6).
ENVIRONMENTAL STATEMENT
Tywyn Coastal Defence Scheme
12
1. Introduction and Background 1.1 Introduction
Cyngor Gwynedd Council (CGC) proposes to undertake a coastal defence scheme in Tywyn. The
scheme aims to reduce the amount of water overtopping the seawall at Warwick Place and
improve or maintain the amenity value of the beach, which is important to the local community,
visitors and tourists. More information on the detailed aims and objectives of the scheme can be
found in Section 1.6.
The scheme comprises several structural elements:
•••• A rock armour breakwater at Warwick Place, with beach nourishment
•••• A rock groyne near Neptune Road
•••• A rock groyne at Pier Road
•••• A rock revetment at Bryn-y-mor
•••• Replacement of the groyne field
•••• Reconstruction or repair of the slipways and access steps, including the concrete steps
along the length of the promenade and the rock revetment near the Warwick Place slipway
•••• Minor refurbishment of the promenade including construction of Coastal Information Centre
(CIC - this will be subject to a separate planning application in the future. Impacts are not
considered in this ES)
More detail on the scheme elements and their construction can be found in Section 2.
1.2 Structure of Report
The structure of this report is as follows:
• Section 1 - (this section) contains the introduction and background to the project,
including the purpose and structure of the document, the site location and description,
background to the issues, strategic context of the work, project aims and objectives and
the EIA process and alternative options considered
• Section 2 - description of the proposed scheme, detailing the physical characteristics,
construction and operational phases
• Section 3 - consultation process that has guided the development of the scheme and
the impact assessment, including the Scoping process
• Section 4 - assessment of impacts and mitigation measures
• Section 5 – summary, conclusions and recommendations of the EIA
• Section 6 - Environmental Action Plan (EAP)
• Appendices – supporting information and analysis undertaken as part of the EIA
process, including all figures referred to throughout the ES (Appendix A)
ENVIRONMENTAL STATEMENT
Tywyn Coastal Defence Scheme
13
1.3 Assessment Requirements and Legal Considerations
The works require planning permission under the Town and Country Planning Act 1999 (for work
above Mean Low Water) from Cyngor Gwynedd Council (CGC) and consent from the Marine and
Fisheries Agency (for work below Mean High Water Springs) under the Food and Environment
Protection Act 1985 (FEPA), and Coast Protection Act 1949 (CPA).
The Town and Country Planning (Environmental Impact Assessment) Regulations 1999 (SI 293)
and the Marine Works (Environmental Impact Assessment) Regulations 2007 (SI 1518) list
projects for which an Environmental Impact Assessment (EIA) is required. The proposed scheme
falls within the lists of projects for which an EIA is discretionary. Given the scheme’s location
adjacent to sites designated under the European Habitats Directive, CGC and CCW considered
an EIA to be needed to assess the potential for environmental impacts. More information on the
Scoping process for the EIA is in Section 3.
This document is the Environmental Statement (ES), prepared as part of the EIA process, in
accordance with the Marine Works (EIA) Regulations and the Town and Country Planning (EIA)
Regulations, to accompany both the planning application and FEPA/CPA application for the
Scheme.
1.3.1 Habitats Regulations Assessment (HRA)
The EU Habitats (92/43/EEC) and Birds (79/409/EEC) Directives aim to protect European birds
and species and the habitats that support them, while the Ramsar Convention on Wetlands of
International Importance aims to protect internationally important wetlands.
The Habitats and Birds Directives require ‘competent authorities’ to undertake an ‘appropriate
assessment’ of plans, projects and strategies that are not directly connected to the management
of the site itself and that may have a significant effect on the site. In the UK, there is a similar
requirement in relation to sites designated under the Ramsar Convention (known as Ramsar
sites). This ‘appropriate assessment’ process is now known as a Habitats Regulations
Assessment (HRA). Information to inform a Habitat Regulations Assessment (HRA) has been
included within this report, due to the proposed scheme’s proximity to both EU and Ramsar sites.
In particular, such information is included within Section 4.5.5 and Appendix E.
1.3.2 Crown Estate consent
Much of the foreshore and the seabed in the UK is in the ownership of the Crown. The Crown
Estate Commission (CEC) manages this land on behalf of the Crown and issues leases, licences
and consents for activities and developments on Crown Land.
CGC has a long term lease from the CEC for the Tywyn frontage foreshore. As such, CGC has
notified them of their intention to carry out works within the area of their lease and has undertaken
to write to the CEC to apprise them of the proposed changes once the detailed design has been
finalised.
1.3.3 Environment Agency Flood Defence Consents
The Environment Agency Wales (EAW) has confirmed that the scheme does not require their
formal consent as Flood Defence Byelaw 25 specifically exempts Local Authorities from the need
to apply for consent for work on sea defence structures.
A Flood Consequence Assessment has been undertaken to accompany the planning application.
This is contained in a separate report (Atkins 2009).
ENVIRONMENTAL STATEMENT
Tywyn Coastal Defence Scheme
14
1.3.4 Shoreline Management Policy
The stretch of coastline on which Tywyn is located falls within the area covered by the North
Cardigan Bay Shoreline Management Plan (SMP) (Cardigan Bay Coastal Group, 2002). Table
1.1 sets out the current policies for the Tywyn frontage and the adjacent stretches of coastline.
Table 1.1 Relevant Shoreline Management Plan (SMP) Policies
Management Unit Management Unit SMP Policy
2.3 Penllyn Managed retreat
2.4 Tywyn Hold the line
2.5 Morfa Gwyllt Hold the line
Source: Cardigan Bay Shoreline Management Plan, 2002
Although the policy for the management of the shoreline to the South of Tywyn (Penllyn) is
‘Managed retreat’, EAW, which is responsible for the management of this section of the coast, and
CCW have agreed a short term (25 year) policy to repair any breaches in the defences. This
policy is designed to allow the breeding site for lapwing to be relocated (EAW, consultation
response).
A review of the SMP policies in the area has recently started. This will set out the strategic
direction for the management of coastal erosion and flood risk over the next 100 years, including
the Tywyn coastline and adjacent areas. This scheme does not pre-empt the outcome of the SMP
review and is consistent with existing policy.
1.4 Development Plan policy
The Gwynedd Unitary Development Plan (UDP) was adopted in 2009. The UDP policies
identified below are of most relevance to the proposed scheme.
In respect of proposals to improve the standard of existing tourism facilities Policy D12 states that
such proposals will be approved, providing that they support the development of an identified
theme for a specific destination as identified within the Gwynedd Tourism Strategy and provided
that all the following criteria can be met:
• That the development is located within a development boundary or makes use of an
existing building or a previously developed site
• That the scale, type and character of the proposed development is appropriate for its
urban/rural setting
• That the proposed development is of high quality in terms of design, layout and
appearance
• That the site is genuinely accessible to a variety of modes of transport which enables
customers and staff to reach the site without having to use the private car
Policy CH17 states that proposals to provide infrastructure will be approved provided that all the
following criteria can be met:
ENVIRONMENTAL STATEMENT
Tywyn Coastal Defence Scheme
15
• That the scale and design of the proposed development is suitable for the location and
site
• That the development will not have an unacceptable impact on the landscape, the coast,
biodiversity, or historic areas/ features, particularly within or near designated areas
• That the development will not have an unacceptable impact on the amenities of
neighbouring residents or sensitive uses
• That the development is acceptable in terms of parking , traffic and road safety
Policy B13 - protecting the open coastline states:
“Outside the Heritage Coast, only proposals that need to be located on or in close proximity to the
coast or estuaries will be approved provided that they do not have an unacceptable impact on the
open character, water quality, public access or ecological balance of the area due to its location,
noise, scale, form, appearance, materials, noise, emissions or due to an unacceptable increase in
traffic.”
Policy B14 - protection of international nature conservation sites
Proposals not necessary in order to manage a site, and which are likely to have a significant direct
or indirect unacceptable impact (either individually or in combination with other plans or projects)
on the integrity of Special Protection Areas (potential or classified), Special Areas of Conservation
(proposed, candidate or designated), Ramsar sites (proposed or listed) will be refused unless all
the following criteria can be met:
• There is no alternative solution
• There are imperative reasons of over-riding public interest for the development or land
use change which override the ecological importance of the site
• In case of sites where priority habitats or species are affected, the only considerations
which could justify granting planning permission are those associated with public health,
public safety or those that bring benefits of primary importance for the environment
and that proposals meet all the following requirements:
• a. the location, design and construction of the development is such that damage to
nature conservation features are minimised, and opportunities for nature conservation
gain are taken
• b. compensating and equivalent nature conservation features are provided
• c. the remaining nature conservation features are protected and enhanced and provision
is made for their management
• d. opportunities are provided for the public to enjoy and interpret the site
1.5 Location and Site Description
1.5.1 Location
Tywyn, is a small seaside town on the west coast of Wales in Cardigan Bay between the Afon
Dysynni (to the North) and the Afon Dyfi (to the South), within the county of Gwynedd (Figure 1 in
Appendix A). It has a population of 3,266 (NSO, 2009).
ENVIRONMENTAL STATEMENT
Tywyn Coastal Defence Scheme
16
Tywyn is a popular holiday and visitor destination, offering a variety of accommodation, from
hotels and B&Bs to self catering cottages, caravans and camp/caravan sites. The area offers a
variety of activities and tourist attractions, including walking, sailing and water sports (e.g. surfing
and fishing), golf, bird watching, general amenity of the beach, historic and archaeological sites,
the steam railway and local farm-based tourist activities such as archery, shooting and quad
biking.
The town is low-lying and comprises a mix of mostly residential and tourism developments
(caravans), along with small shops, cafes and pubs/restaurants.
The coast adjacent to the Tywyn frontage to the South (Penllyn) is fronted by sand dues, which
are regularly recharged with sand by CGC. Behind the dunes, the land is low lying. The Aberdyfi
Golf Course runs along the coast, between the beach and the A493. This stretch of coast is within
the Dyfi Estuary Site of Special Scientific Interest (SSSI).
Adjacent land to the North is also low lying and used mainly for agriculture. Between the Afon
Dysynni and Tywyn, the Cambrian Coast railway runs along the coast, before heading inland,
through the town. Where the railway line is closest to the shoreline, there are rock revetment
defences, which are managed and maintained by Network Rail. These defences have been
upgraded with more rock within the last 12 months. Behind the railway line, the land is low lying
much of the area is within the Broadwater SSSI. There is a small waste water treatment works
approx. 350m North of the Tywyn promenade.
The hinterland is dominated by hills, which are part of the Snowdonia National Park (SNP), which
encircles the town and includes foreshore areas to the North and South. Tywyn, however, is not
within the SNP. Figure 1 in Appendix A shows the location of the town and the area within
which the works are proposed.
1.5.2 Site Description
The coastal frontage is in total 1.8km, comprising a 465m Victorian promenade, with 360m of
additional walkway to the South and a 975m promenade to the North. The Victorian Promenade
was built in 1890, followed later by a promenade to the North of Sandilands Road, which was
destroyed by a storm in about 1935. The remainder of Tywyn’s frontage has developed in an ad-
hoc fashion. The first modern phase was built in 1966 between Pier Road and Sandilands Road -
half was a formal concrete sea wall and the remainder was rock armour contained by a bull head
rail crib. The area between Warwick Place and Neptune Road was constructed in 1967/69. The
area from Sandilands Road North was built in 1977. The frontage was completed to its current
state in the mid 1980s when the rock armour and bull head rail to the North of Pier Road were
encased in concrete to create a formal sea wall.
1.6 Background to the Scheme
The Tywyn coastal frontage has suffered several significant damaging events, experiencing storm
damage in nearly every decade since the 1930s and emergency works have been required on
numerous occasions. Over the last 100 years, the height and width of the beach has also
receded. Over this time, the beach level at Warwick Place has dropped by 3m.
The installation of timber groynes in the 1970s reduced the rate at which the beach receded but
has not reversed it, and overall beach recession is expected to continue. In the last 10 years the
rate of beach lowering at certain locations along the frontage has been greater than the long-term
average, leading to overtopping of the current defences and flooding during storm events. The
erosion of the beach, combined with the deterioration of the groynes has contributed to the sea
wall being undermined, particularly at Bryn-y-mor.
ENVIRONMENTAL STATEMENT
Tywyn Coastal Defence Scheme
17
In 1993 Meirionnydd District Council (MDC) (now CGC) and the Shoreline Management
Partnership formally raised concerns regarding the defences along the Afon Dyfi to Afon Dysynni
coastline in the Meirionnydd Coastal Management Study. The study recognised that falling beach
levels fronting the sea defences were exposing the hinterland developments to increased risk of
tidal flooding, whilst the sea walls were becoming more susceptible to undermining and collapse
during storm events.
The land behind the sea wall is relatively flat, meaning that overtopping sea water is able to flow
inland relatively freely. Flooding is most prevalent at the Southern end of the promenade at
Warwick Place. The most severe recent flood events occurred in the following years:
• February 1997 – Tywyn Promenade flooding
• February, 2002 – Overtopping from an estimated 25.5m3/m to 55.4m
3/m run of sea wall.
The storm event data suggests that a water level of between 3.0m and 3.7m AOD and a
wave height between 2.5m and 3.2m contributed to flooding along marine parade.
Flooding over large areas reached a depth of 0.3m (CES, 2006)
• February, 2007 – Warwick Place inundation and shingle build up on promenade
• March 2008 – Warwick Place inundation and road closure
Since 2002 CGC have spent over £250,000 carrying out emergency / essential works in the Bryn-
y-mor area and some £10,000 of revenue money on minor repairs, mainly on the Victorian
Promenade area.
The United Kingdom Climate Impacts Programme (UKCIP) and Marine Climate Change Impacts
Partnership (MCCIP) predict an increase in storminess and wave height in coming years.
Continued recession of the beach is increasing the risk of damage to the sea wall and from future
flooding events, particularly in the light of climate change impacts. Whilst it has been possible to
repair the sea walls and replenish the beaches following storm events to date, this approach is
expected to become unsustainable in the context of sea level rise and increased storminess as a
result of climate change.
In December 2004, the Welsh Assembly Government (WAG) confirmed that a scheme could be
eligible for funding if it were to meet the required technical, environmental and economic criteria.
In 2009, WAG confirmed that CGC had been successful in their bid for EU Convergence Funding
• European site citations, data forms, Regulation 33 advice and Management Plans
• Traffic Impact Assessments (TIA) of Delivery Option A and Delivery Option B,
undertaken by Gwynedd Consultancy in 2009
Where additional sources of information have been used for the assessment, these have been
stated at the start of each section.
For each receptor the following information is set out:
• The baseline conditions – information has been obtained from previous surveys, the
2005 Scheme ES, consultation with statutory and non-statutory consultees and validated
by a walk over survey in May 2009
• The methodology employed to undertake the assessment of potential impacts and
justification for its use. In addition, the source of potential impact, the pathway to the
receptor and the location of sensitive receptors (source – pathway – receptor) were all
clearly identified;
• Assessment and mitigation of impacts during construction – this sets out the potential
impacts on the receptor in question that could occur during the construction of the 2009
Scheme. This is based on the design details and the construction approach set out in
Section 2. Possible impacts within the area of the scheme and outside the area of the
scheme are presented
• Assessment and mitigation of impacts post construction - this sets out the potential
impacts on the receptor in question that could occur after the 2009 Scheme has been
built. This is based on the operational management details set out in Section 2.
Possible impacts within the area of the scheme and outside the area of the scheme are
presented
The criteria that have been used throughout the assessment of the various receptors to determine
the magnitude of the effect is outlined in Table 4.1 below. These criteria have been derived by
Atkins from our expertise in undertaking EIAs and have been adapted for the assessment of
potential impacts associated with this project.
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Table 4.1 Impact Assessment Criteria
Term Definition
Effect
Adverse An impact that would have a detrimental impact of a given magnitude on the existing environment
Beneficial An impact that would have a positive impact of a given magnitude on the existing environment
Magnitude of Impact
Major Substantial impact on an environmental feature; adverse impacts likely to result in loss of integrity of the feature; beneficial impacts likely to result in addition to or enhancement of the feature
Moderate Impact on a noticeable proportion of an environmental feature; adverse impacts will represent a risk to the feature; beneficial impacts could result in enhancement
Minor The impact will be measurable but of limited proportion, degree or extent; adverse impact will not represent a significant risk to the environmental feature
Neutral No measurable impact will occur
Duration of Impact
Temporary The effects of the impact will last for the duration of the construction period
Permanent The effects of the impact will extend for longer than 10 years
The assessment considers both adverse and beneficial effects and this is stated for each impact
identified. Impacts are highlighted in bold in the text. Section 5 contains a summary of all
impacts and conclusions of the assessment.
The assessment of the magnitude of effects has been carried out using published data,
professional judgement and numerical modelling, where appropriate.
Where adverse impacts have been identified, mitigation measures are proposed to minimise or
compensate for these impacts. Mitigation will seek to reduce the impact to an acceptable
standard for that specific receptor, or eliminate the impact entirely.
Mitigation measures, and any other actions which could be required, such as further surveys or
works to ensure legal compliance, are detailed within the Environmental Action Plan (EAP),
contained in Section 6. The EAP will be incorporated within the contract documents and
contractor’s method of working to ensure that all issues identified within this EIA are addressed
whilst on site.
The assessment has also identified the impact of the scheme in-combination with other
construction activities which may be taking place in the area and which may exacerbate potential
impacts.
4.4 Geology and Coastal Processes
This section considers the present understanding of the coastline around Tywyn, the physical
processes controlling the coast and the effects of the proposed scheme on both the local and
wider environment.
4.4.1 Method of Assessment
The assessment of the geology and coastal processes has been undertaken through the following
mechanisms:
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• Review of existing literature - in particular the assessment carried out for the 2005
Scheme by ABPmer (ABPmer, 2004a), which also included physical modelling of the
2005 Scheme.
• 1D and 2D numerical modelling - carried out by Atkins specifically for the purposes of
the 2009 Scheme, including:
- Understanding existing wave conditions and sediment transport processes
- Modelling of coastal processes ‘with 2009 Scheme’
• Geotechnical site investigation – a series of boreholes of the Tywyn foreshore were
taken in July 2009 (report in preparation for CGC).
Timescales referred to in this coastal process section are based on Shoreline Management Plan 2
definitions (Defra 2006b – SMP2 guidance). This reflects the agreed timescales and Government
(Defra and WAG) guidance for which coastal processes should be managed and planned.
• First epoch - 0-20 years
• Second epoch - 20-50 years
• Third epoch - 50-100 years.
4.4.2 Baseline Conditions
The baseline conditions at the site and within the area local to the site are key to developing an
understanding of the ongoing physical processes. From this baseline it is then possible to
develop an understanding of the potential impacts, positive or negative, of the proposed scheme.
Where site-specific information is not available proxies from up and down the coast have been
used. The key aspects of interest for the coastal process are:
• Waves
• Tidal & Fluvial Flows
• Geology
• Sediment Dynamics & Transport
• Geomorphology
• Climate Change
The environment around the Tywyn frontage consists of a large curving bay between two
controlling points, the Sarn-y-Bwch (shallow subtidal reef comprising mixed sediments of glacial
origin) to the North and the Aberdyfi Bar to the South (see Figure 1, Appendix A for site location).
In the centre of this bay is the developed Tywyn frontage itself extending for approximately 1.8km
with seawalls, timber groynes and rock revetment. To the North the semi natural beach extends
up to the training wall at the mouth of the Dysynni with one section of rock revetment providing
protection to the Network Rail assets where they approach the coast. To the South the beach is
backed by sand dunes, in some places up to 9m high down to the entrance to the Afon Dyfi.
Waves
Waves arriving at the Tywyn frontage are either locally generated wind-sea waves or longer
period swell waves from the Atlantic (see Table 4.2).
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Table 4.2 Wave Data
Wave
Condition
Generation Location Typical Height
(m)
Typical Period
(s)
Typical Direction
(deg N)
Wind-sea Cardigan Bay/St Georges
Channel/ Irish Sea
0.5-3.5 2-7 250
Swell North Atlantic 1-8 7-12 245-260
Source: Met Office UK waters wave model (2009) for the year 2003
These waves propagate across Cardigan Bay from a variety of directions depending on the
generation process and as they approach the shore they are refracted to become perpendicular to
the coastline in the very nearshore. An example of the difference between the offshore and the
nearshore wave conditions is given in Figure 26, Appendix A. This shows that there is greater
variation in the direction of propagation for nearshore waves than for offshore waves. Offshore
waves are predominantly from the West-Southwest (>35%), with few from other directions (approx
10% from South-Southwest). Nearshore waves are also predominantly from the West-Southwest
(approx 30%), although a greater proportion are also generated in the South-Southwest (approx
20%) and West-Southwest/West-Northeast (approx 10%).
The wave patterns across Cardigan Bay are complicated by the interaction with the major seabed
features of the Sarn-y-Bwch (to the North and the ebb tidal delta of the Afon Dyfi. At the Northern
end of the coastline the Sarn-y-Bwch affords additional protection to infrequent wave conditions
from the North (Atkins, 2009), whilst the remainder of the Tywyn Bay becomes increasingly
exposed. At the Southern end the shifting presence of the ebb tidal delta leads to changes in the
wave penetration into the estuary and on the adjacent shoreline.
The prevailing wave direction is between 245 - 260ºN (Southwest/West-Southwest) along much of
the frontage (CGC, 1998). Inspection of charts and maps of the area indicate that the shoreline is
orientated perpendicular to this, suggesting the coastline is ‘swash’ aligned, limiting the potential
for a dominant longshore transport direction of sediment by wave movement.
The largest waves seen along the frontage are from 225-255ºN with typical annual heights in the
range 3.6-4m. Extremes analysis (ABPmer, 2004b) and re-analysis of the latest wave data
(Atkins, 2009) suggests 1 in 1 year waves of 8.9m and 1 in 100 year storm waves of 13.4m in the
offshore environment of Cardigan Bay. These extreme waves would be limited in height at the
nearshore by the processes of wave breaking, which is principally controlled by the water depth.
It is important to note that the wave climate is subject to large natural variability on seasonal, inter-
annual and longer term timescales. This has a significant impact on the nearshore wave climate
and subsequently the sediment transport processes. In addition, the occurrence and sequencing
of storms can alter the coastal processes.
Tidal and Fluvial Flows
The Tywyn coastline is classified as mesotidal with a tidal range of 2-4m. The principal tidal levels
for the closest port, Aberdyfi, are shown in table 4.3.
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Table 4.3 Tidal and Extreme Water Levels for Aberdyfi
Return Period Level mAOD
1 in 100 4.4
1 in 1 3.7
HAT 3.56
MHWS 2.56
MHWN 1.06
MSL 0.17
MLWN -0.44
MLWS -1.74
Sources: Admiralty Tide Tables, 2008 and ABPmer, 2004
The variation in water level results in a typically Northeast/Southwest tidal flow in the offshore
zone with peak spring tidal velocities of 0.5m/s to 0.3m/s, with the tidal residual for the area being
a net Northeasterly flow (Tidal Diamond Admiralty Chart, 1972).
More complex tidal flows are found around the estuary mouths to the North and South of Tywyn
(ABPmer, 2004a), including an interaction with the freshwater outflows from the Afon Dyfi and
Afon Dysynni. In addition two outfalls can be found along the Tywyn frontage. To the North of
Tywyn is the Welsh Water Main drain outfall and to the South the Afon Dyffryn Gwyn. These
outfalls have fixed structures therefore their impact is principally on introducing fresh water into the
coastal zone rather than altering the wider geomorphology.
The Afon Dyfi is the larger of the two estuarine systems with gauging at the Dyfi Bridge indicating
a mean daily flow of approximately 23m3/s whilst flow on the Dysynni is approximately 5m
3/s
(ABPmer, 2004a).
Geology
The geology of the Tywyn coastline has been heavily influenced by the historically glacial nature
of the surrounding environment. The ice ages have led to glaciers eroding the highlands and
depositing material in Cardigan Bay. Subsequent sea level rise has led to migration of the deposit
points towards the coast. The present day geology is influenced largely by the end of the last ice
age and events during the intervening Holocene period (ABPmer 2004a)
The principal geological features left by this interglacial period are the sarnau (reefs) of Sarn-y-
Bwch to the North of Tywyn and Sarn Cynfelyn to the South of Borth. These large intertidal
causeways are thought to be glacial moraines formed during periods of ice retreat and consist of
boulders and finer material. The transgressive nature of sea levels in the Holocene has led to the
reworking of glacial material and subsequent roll back of the coastline to its present position.
(Halcrow, 2001) This leaves a “spit” of more resistant glacial tills that form the basis for the town of
Tywyn (see Figure 27, Appendix A). Either side of the resistant glacial tills of Tywyn are more
erosive geological forms consisting of peat, sand dunes and other marine material. Finally, the
estuaries at the Afon Dyfi and Afon Dysynni, which are historically buried river valleys formed by
the passage of the glaciers, are now sinks for large quantities of marine material. On top of these
features lies the present day foreshore consisting of marine deposits of sands/gravels that are
constantly re-worked by the coastal processes.
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The Dyfi SSSI to the South of the Tywyn site is notified for both its geological and biological (see
section 4.5) features. Of note for the geology is the record of coastal and environmental changes
through the Holocene period provided by the marine clay deposits and the peat associated with
the submerged forest. In addition the Dyfi estuary is considered important for the information
contained with respect to coastal geomorphological evolution. It should be noted however that the
proposed site is outside of the SSSI and the closest observed peat beds (at the Afon-Dyffryn-
Gwyn) are also outside of the SSSI. Ground investigations carried out in summer 2009 for this
project have identified no peat beds within the proposed area of the works.
Beach Sediment Composition
A series of ground investigations are available for the coastal frontage at Tywyn including trial
holes and more detailed boreholes by CGC (2001) and Atkins (2009). In addition, long term
beach profile monitoring by CGC provides details of the sediment composition of the surficial
marine deposits. The beach is termed a mixed beach with both sand and shingle/gravel being
present.
Much of the lower foreshore is composed of sand overlying boulder clay or till. The depth of the
sand ranges from ~1m to zero with sections of the boulder clay being exposed at the Bryn-y-mor
end of the frontage as a result of erosion. Behind this an ephemeral shingle/gravel ridge forms
the upper foreshore control, providing protection from storm waves where it is present. To the
South of Tywyn this ridge affords some protection to the wind blown sand dunes behind. The
sand dunes are up to 9m high in some locations and well vegetated on the upper faces.
Undercutting of the dunes has been observed in response to coastal processes with a current
programme of works to re-nourish some areas with additional sand.
The sand on the foreshore is typically medium to coarse sand with a D50 (average diameter) grain
sizes between 0.3 and 0.5mm (ABPmer, 2004a and Atkins, 2009). In the upper foreshore, the
shingle/gravel material D50 is typically 2-200mm. These sediment sizes, in conjunction with the
principal coastal processes, control the possible foreshore slopes. On the sand foreshore the
slope is between 1:100 and 1:50. Higher up the beach the shingle resides at angles between
1:15 and 1:8 (Atkins 2009). From the Afon Dyfi in the South and progressing North past the
Tywyn frontage the foreshore shows a tendency to steepen and narrow (See Figure 28,
Appendix, A)
Beyond the Lowest Astronomical Tide (LAT) there is limited information on the sediment
composition, however sources (Admiralty Chart 1972, Halcrow, 2001) suggest much of the
material is sand with rock outcrops out to the -15m contour. Beyond this the sediment is gravel
with pockets of sand. This offshore sand source is considered similar to the onshore sand with
typical depths of ~1m to a boulder clay layer below (ABPmer, 2004a).
Sediment Dynamics & Transport
Sediment transport in the wider Cardigan Bay is characterised by a predominantly, wave-driven
Northerly drift of material (Halcrow, 2001) for both bed load and suspended load. The more
complex nearshore features of the Sarnau and the ebb tidal delta of the Afon Dyfi influence the
inshore wave patterns and locally alter the wider scale Northerly drift.
The swash aligned nature of the coastline immediately around Tywyn has led to a divergence of
opinion on dominant local sediment transport processes (ABPmer, 2004a). Many studies are
available (CGC, 2003; CGP, 2000; HR Wallingford, 1999; Pethick, 1996) with conclusions ranging
from net Northwards to net Southwards movement. These studies typically utilised measured
data to suggest magnitude of drift and used inference from the geomorphological features, such
as the Northwards spit orientations at the Afon Dysynni and Dyfi and sediment sources such as
the Tonfanau cliffs for direction. ABPmer (2004a) proposed a systems-based approach to
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develop the understanding of the sediment transport on the Tywyn frontage. This provides a
framework for the sediment budget based on available information, including constraints,
processes and availability of sediment. The ABPmer sediment budget is shown in Figure 29,
Appendix A.
This sediment budget shows the principal components of the system being the low longshore
transport rates (average of 1,500m3), the sediment sinks of the Dyfi and Dysynni (37,000 and
2,000m3) respectively and the significant shoreface source of between 18,000-45,000m
3. The
shoreface in this sediment budget is considered to include the entire frontage (~9km long) out to
approximately the -10mCD contour. It is important to note that in this analysis the role in the
sediment budget of the sand dunes to the South of Tywyn is limited, with volumes considered to
be net zero following erosion/accretion events. The primary conclusion from the ABPmer work
was that it appeared practical to regard sediment transport as being bi-directional and relatively
low in terms of the volume moved, with the most significant aspect being the cross-shore transport
of sand from offshore to onshore. The balance of the budget ranged from -8,000m3 to +80,000m
3
which would suggest that the sediment provided to the beach must be made available from the
offshore sand source.
More detailed sediment transport studies by Atkins (2009) confirms this hypothesis with typical
annual drift for 2003 (considered a-typical in the offshore climates) showing gross
offshore/onshore transport rates 3-4 times the net rate of Northerly transport (3,000-9,000m3).
However this was then reversed to Southerly drift in the longer term climate analysis, highlighting
the sensitivity to alterations in the offshore wave direction. This work also highlighted the
importance of the mixed sand/shingle beach in understanding the coastal processes.
It is proposed that in addition to the sediment budget breakdown proposed by ABPmer (2004a),
the foreshore is split into its two parts consisting of the sand lower foreshore and shingle upper
foreshore to enable a conceptual understanding of the processes involved. The sand component
is typically a ‘veneer’ on top of harder sub-surface geology up to 1m deep. Overlying this sand
material at the back of the beach is shingle/gravel material.
The sand component can be considered to be the foundation of the mobile beach, providing the
majority of the sediment source. The shingle material is more ephemeral in extent and subject to
volatile movement in response to strong wave events, in particular where it is fronting more
prominent less sheltered sections of the defences (such as Bryn-y-mor and Warwick Place).
Consequently it is the shingle material that is observed to be retreating (or not present).
The sand part of the foreshore still provides an important foundation material to the beach. This is
supported by recent detailed 2D topographic data analysis of the foreshore at Tywyn (Atkins,
2009) which shows that the lower sand part of the foreshore has accreted by up to 700mm over
the period 2002 - 2009. Conversely the upper foreshore has eroded by up to 400mm. This is set
against a background environment where the beach in front of Tywyn appears to be losing a
volume of approximately 20,000m3 (or 5% of the 2002 volume) over the same time period.
Further analysis of the area below MLWS (beyond the extents of the regional monitoring surveys)
is possible by using process-based models and assessing a series of hypothetical scenarios.
Atkins (2009) has undertaken model investigations to assess the relative importance of the
observed beach in comparison to that below MLWS. This has shown that of the active sediment
transport zones, the foreshore around MLWS makes up the majority of the longshore drift
assuming a sand/shingle mix.
In addition the cross shore modelling has shown that the null point (the zero point between
onshore and offshore transport) is around MLWS with a net onshore transport seaward of MLWS
and net offshore transport on the upper foreshore. It should be noted that single storm events can
move more sand offshore than a whole year of typical conditions, suggesting that the offshore
zone is recharged with sand from drawdown of the beach, which is then made available to the
beach again. It is apparent from the detailed 2D topographic survey that the beach can respond
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within a season to these events, suggesting that there is enough material to maintain this process
at present.
The sediment transport processes have important implications for the long term sustainability of
the beach system. It shows that there are two zones of longshore sediment transport, one out on
the low tide flats fed by the offshore zone and one on the upper beach. The upper beach zone is
comprised of coarser material, which therefore has a lower drift potential.
Beyond the upper beach the dune system to the South of Tywyn currently suffers from localised
blowouts. The work of Pye & Associates Ltd (2005) states that lateral frontal dune erosion is
prevalent though not necessarily rapid at the Aberdyfi site. This is supported by the ongoing work
by the EAW to nourish the dunes. In the longer term it is considered that there will be a small net
loss of fixed dune at Aberdyfi due to the steepening of the foreshore and the hold the line policy.
Over the last 150 years the beach at Tywyn has been observed to be lowering, suggesting less
material is available for beach building and subsequent transport. The current work (Atkins, 2009)
suggests that whilst shingle material is becoming scarce on the immediate Tywyn foreshore the
presence of an onshore push of sand material has been providing a feed to the lower sand part of
the foreshore. ABPmer (2004a) suggest that the source of sand sediment in this offshore zone
may be becoming depleted as well. The transport results shown above seem to suggest that the
material coming onshore will be moved up and down the coast by longshore sediment transport.
Whilst the net rates of longshore transport are low, the gross transport can be enough to move up
to 50,000m3 of material. This could allow sand to circulate to the offshore source via Sarn-y-
Bwch, the Aberdyfi Bar or an intermediate pathway during storms. This postulated circulation
pattern is supported by the Futurecoast work (Halcrow, 2001) which suggests a circulation around
Tywyn bay between the Sarn-y-Bwch and the Aberdyfi Bar.
The scarcity of shingle material, whilst a concern with respect to overtopping for areas where the
protection at the upper foreshore is limited, does not suggest that the beach as a whole is being
lost. Conversely the build up of sand material on the intertidal foreshore suggests that there is still
input of this finer fraction. This helps to break the wave energy offshore of the coastal defence
structures and maintains the aeolian transport link to the sand dunes to the South of Tywyn. This
could even be beneficial to the sand dunes if they are allowed to roll back ‘naturally in the future
rather than holding the line (existing short term policy agreement between CGC and EAW).
Geomorphology
Beach Development History
Historically the beach has been seen to be lowering at Tywyn over the past 150 years. The effect
of this lowering on plan shape has been a retreat of the shoreline. Work undertaken for the
previous schemes has been based on long term monitoring since the late 19th
Century (Shoreline
Management Partnership, 1994 and 1995) and has provided detailed estimates of recession.
ABPmer (2004a) updated the recession analysis which confirmed the movement of MLW and
MHW with typical rates of 0.3m/yr and 0.7m/yr suggesting an average intertidal recession of
0.5m/yr. The data also suggests that the foreshore has steepened over time, a fact supported by
the Futurecoast study (Halcrow, 2001) and Atkins’ recent work.
Atkins’ use of numerical process based models has shown that the recession of the coastline is
largely independent of the direction of drift, with recession taking place in response to
protuberances in the coastline. This is the effect of the wave climate acting to smooth the bay into
a large curve. The swash aligned nature of the frontage means that in terms of alongshore
transport the total amount of material remains the same and it is the location of this material on
the frontage that leads to erosion/accretion patterns. This highlights the importance of the
onshore/offshore sediment source and interaction with larger sediment circulation patterns on
controlling the sediment available for beach building.
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Embayment Formation
As the coastline is swash aligned ABPmer (2004a) proposed using equilibrium bay shapes to
describe the historical evolution of the frontage and the current situation. Equilibrium bay shapes
are based on the theory that a beach will find a natural equilibrium between hard points or
headland controls. On the Tywyn frontage the principal controls on the overall formation are the
Sarn-y-bwch and the Aberdyfi bar. The geologically harder glacial tills at Tywyn also form a
control, with an embayment forming to the North and to the South of the Tywyn. This has been
accelerated by the hardening of the frontage with the placement of the coastal protection
structures. The effect of headland control can also be seen on this hardened coastline with
smaller scale headlands at Warwick Place and Bryn-y-mor and a bay forming between these two
points.
Evolution of this bay system into the future is likely to be driven by climate change, principally the
changes in sea level. The current transgressive nature of sea levels suggests that the position of
the larger bay shapes will continue to retreat into the bay leaving Tywyn as a promontory due to
its geological make up. The time scales of this change are likely to be centuries and there is
uncertainty over the impact of changes to storminess and associated directional change on this
process.
Climate Change
Climate change for coastal development is principally concerned with the likely future sea levels
and the changes to wave height and direction. Historical records suggest rates of 2mm per year
(ABPmer 2004a) for sea level rise in Cardigan Bay. Currently information is being updated on the
likely impacts of sea level rise in line with UKCP 2009. Table 4.4 below shows a comparison of
the recent changes to Sea Level rise guidance.
Table 4.4 Sea level rise predictions relative to 1990 base level
2003 Guidance Supplementary Guidance
October 2006 (Wales)
UKCP 2009 guidance for Cardiff
(mm from 1990 base year)
5mm/yr 3.5mm/yr 1990-2025
8.0mm/yr 2025-2055
11.5mm/yr 2055-2085
14.5mm/yr 2085-2115
Year High Med Low
2000 35 29 25
2010 73 62 53
2020 115 97 82
2030 159 40 114
2040 208 175 148
2050 259 218 184
2060 314 263 222
2070 371 311 263
2080 433 362 305
2090 497 416 350
2095 531 444 373
250mm over 50 years 287.5mm over 50 years 259mm over 50 years for the high
scenario
Sources: Defra 2003, Defra 2006a, UKCP 2009
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These results show that typically the increase in sea level up to 2050 is likely to be between
250mm and 290mm. It should be noted that in addition to the High scenario shown above there is
a High-plus-plus (H++) scenario that suggest maximum increases in water level around the UK
will range between 930mm and 1090mm at 2095. This forms the extreme upper limit to the
scenarios.
What is important in terms of coastal processes is the ability of the coastline to respond to these
changes in sea level. Historically, coastal processes have responded to sea level rise, as shown
by the transgression since the last ice age. If the rate of rise is greater than historically, then it is
possible that sea level rise will overtake the speed with which the coastal processes can respond
and influence the geomorphology, leading to rapid loss of coastal features, such as shingle
ridges/dune systems as seen in the Solent (Bray et al, 2004).
For wave climate the UKCIP predictions are suggesting a small increase in winter wave heights
for both mean and extreme conditions. Changes in the winter mean wave height are projected to
be between –35cm and +5cm. Changes in the annual maxima are projected to be between –
1.5m and +1m. Changes in wave period and direction are rather small and more difficult to
interpret therefore there is little information on this. The impact of changes in wave height is likely
to be limited, with the depth limiting conditions at the shore being linked to changes in water level
rather than offshore wave conditions. Changes in period and direction may alter the magnitude
and direction of sediment transport to a greater effect, but the limits of this change with respect to
the current inter annual variability will determine the magnitude of this impact on the coastline.
4.4.3 Assessment and Mitigation of Impacts during Construction
During construction there is a limited risk that the works could release sediment into the sea,
through the movement of construction vehicles on the beach, excavation on the foreshore and/or
placement of nourishment material, which could temporarily alter the existing sediment budget
both within the site and immediately adjacent. However, methods will be undertaken during the
work to minimise the release of sediment to reduce impacts on marine flora and fauna as well as
water and sediment quality (see sections 4.5 and 4.7).
The construction is scheduled for a period of 18 months and there could be a risk that a lag in
between the construction of some aspects of the scheme could cause small scale erosion and/or
accretion, albeit temporary and localised. This is only a risk for the rock structures. For example,
if there is a time lag between construction of the Warwick Place Breakwater and the nourishment
in its lee, the breakwater could trap material from adjacent sections of beach, causing short term
localised erosion.
The route for transportation of construction vehicles across the beach will be within the confines of
the groynes 01 and 34 and there will therefore be no tracking on the adjacent peat beds to the
south which are situated within the Dyfi SSSI.
The construction programme will be arranged so that complimentary structures are constructed at
similar times. The impact of the construction programme on coastal processes is considered to
be neutral.
4.4.4 Assessment and Mitigation of Impacts Post Construction
Introduction
The 2009 Scheme seeks to work with the existing coastal processes to reduced the risk of
impacts from coastal erosion and flooding along the Tywyn seafront. Coastal processes and in
particular sediment transport are subject to large variability in space and time. Consequently it is
difficult to determine absolute effects, but it is possible to outline likely envelopes of conditions.
For this assessment these effects have been split into those within the site (between groynes 01
and 34, see Figure 2, Appendix A) and those impacting the wider environment with subsections
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for first SMP2 epoch (0-20 years) and the second SMP2 epoch (20-50 years) effects. This
recognises specific concerns raised by CCW during the consultation on the Scope of the ES (see
Section 3 for more detail). Impacts beyond 50 years (third SMP2 epoch) would be too
speculative and therefore have not been considered.
For the assessment of effects it is important to consider the impact of non-intervention on the
coastline. Best estimates of this scenario (ABPmer 2004b, Atkins 2009) suggest that Tywyn will
become a promontory along the coastline leading to the formation of two separate bays to the
North and South. As sea levels rise, the coastline will seek to retreat primarily through the softer
materials to the North and South of Tywyn, with increased potential for breach through the natural
defences to the low lying land behind. Over longer periods of time (50-100 years) the harder
geology at Tywyn will be subject to erosion leading to slow retreat of the headland. Longshore
transport rates are also predicted to increase in the future as a result of sea level rise and
changed wave patterns (ABPmer 2004b). This scenario is dependant on the evolution of both the
Sarn-y-bwch and the Aberdyfi bar as headland controls and the estuarine morphological response
to sea level rise.
It is from this position that comparison with the baseline can seek to understand the likely effects
of the 2009 Scheme on the coastal processes. Due to the position, type and location of the 2009
Scheme, the major resultant impacts are likely to be limited to changes in the sediment transport
regime and subsequently the geomorphology. These are assessed below based on the short and
medium term for locations within and outside of the site.
Within the Site – First SMP2 epoch (0-20 years)
Assessment of Impacts
Within the site the alteration to the wave climate and hence the sediment transport potential will be
limited to the immediate area around the Warwick Place Breakwater and the two control structures
(Pier Road and the South Terminal Rock Groynes).
The Warwick Place Breakwater’s principal purpose is to reduce wave overtopping at the critical
section of the Victorian Promenade, leaving a shadow zone behind in which wave heights are
reduced. The Pier Road and South Rock Groyne are in place to limit the extent of beach recharge
required and to provide limiting controls to the structure. The Warwick Place Breakwater itself will
also reduce wave reflection from the existing seawall as the proposed rock armour will be more
dissipative. This then has a knock on effect on flows and subsequently sediment transport in this
zone will reduce, leading to increased sedimentation in this zone. The extent of this effect is likely
to be limited to the immediate environment around the breakwater. Consequently whilst a
beneficial impact will be felt with respect to the flooding and overtopping at the site the net impact
of the Warwick Place Breakwater on coastal processes is likely to be minor adverse in the short
term whilst the system adjusts to the new structure and is dependant on the timing and success of
the nourishment scheme.
In terms of plan shape evolution with respect to sediment transport, ABPmer (2004b) applied
equilibrium bay theory to the 2005 Scheme to ascertain the likely equilibrium beach forms
(assuming enough sediment was available). Atkins has reapplied the same methods (2009) to
assess the layout of the current scheme.
ABPmer found that due to the swash alignment of the coast, the bay formation was sensitive to
the wave angle, however, the formation was dependant on the availability of sediment. Atkins’
analysis confirmed that there was not enough sediment for the 2005 Scheme and that there may
still be a deficit for the 2009 Scheme to form full equilibrium bays at all locations. This would
suggest that material could be drawn in from adjacent parts of the Tywyn frontage which could
have a minor adverse impact.
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The physical modelling undertaken by ABPmer showed that the formation of a salient in the lee of
the Warwick Place Breakwater could be disturbed by large storm events. This would suggest that
the physical conditions at the breakwater are enough to re-initiate sediment transport in the lee of
the Warwick Place Breakwater, with the conclusion that the likelihood of complete sediment
interruption at this location is low. Consequently it is likely that the 2009 Scheme, which includes
beach nourishment, will counteract the ability of the Warwick Place Breakwater to draw sediment
in from adjacent parts of the frontage and potentially have a net minor beneficial effect on the
sediment budget by adding to the amount of material on the upper shore, countering previous
losses.
The present pattern of cross and longshore transport on the Tywyn frontage has been discussed
in more detail in Section 4.4.2. It is apparent from inspection of the results of the 1D coastal
modelling (Atkins, 2009) in Figure 30, Appendix A that peak transport occurs in the sand zone
around the proposed breakwater location. This would suggest that if the Warwick Place
Breakwater prevented sediment transport only in the location where it resided it would remove
approximately 35% of the longshore transport. It has, however, already been shown from the
physical modelling results that the area behind the Warwick Place Breakwater is subject to
removal of the salient. When the results of the 1D modelling are considered in light of the 2D
modelling, the findings suggest that the impact of the Warwick Place Breakwater in reducing
longshore drift is likely to be limited. In addition positioning the breakwater at the embryonic
headland (Warwick Place) is the most appropriate as net sediment drift past this point is
approaching the lowest along the whole frontage. Consequently the reduction in drift caused by
placing the breakwater is proportionately less, reducing the impact to neutral.
Further analysis shows that the sand/shingle composition of the beach leads to this sediment
transport pattern. If however the shingle wasn’t present and the upper part of the foreshore
consisted only of sand (a likely scenario as there is a limited supply of shingle on the frontage) the
transport rates would be much higher, as seen in Figure 30, Appendix A. There is a need for a
control structure to limit the loss of any natural or recharged material from the upper foreshore.
The 2009 Scheme will also replace the existing groynes with shorter ones. Analysis of the
longshore drift patterns again shows that the majority of the sand transport is offshore of the
groynes. The purpose of the new groynes is to manage the limited stocks of shingle material on
the upper foreshore. The shingle material has been seen to be in decline on the foreshore as the
likely generating source (the Tonfanau cliffs, Sarn-y-bwch and historically the offshore deposits)
presently have limited inputs to the system. The current sand transport from offshore appears to
replenish the low tide foreshore. This sand then links to the dune systems principally to the South
of Tywyn. The 2009 Scheme does not interrupt the sand foreshore still link to the dunes (i.e. no
interruption of aeolian processes between the two) and, therefore, has a neutral impact on the
dune system.
The location of the Warwick Place Breakwater is immediately adjacent to the Pen Llŷn a'r Sarnau
SAC. The position of the Warwick Place Breakwater has been optimised to ensure no part of the
structure is within the boundary of the SAC as defined by MLW. The Warwick Place Breakwater
will act to reduce wave heights behind the structure through dissipation of the wave energy. The
primary impacts of the structure are in the shadow zone behind the structure. Wave interaction
with the Warwick Place Breakwater may cause localised scour of the sand around the structure
toe, however the extent of this effect is limited. Therefore the impact on the SAC is neutral.
The Bryn-y-mor Rock Revetment also aims to reduce the risk of wave overtopping. Due to its
location at the toe of the seawall it is likely to have a neutral impact on the sediment transport
processes along the frontage, as it will not lead to blockage of the drift along the front. Bryn-y-
mor, like Warwick Place, is located at an embryonic headland therefore has lower sediment
transport potential, reducing further any potential adverse impacts.
ENVIRONMENTAL STATEMENT
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Mitigation
The Tywyn frontage is likely to begin forming two bays to the North and South of town in the short
(0-20 years) term. Analysis by Atkins (2009) also shows that the structures around the Tywyn
headland will form their own series of ‘bays’ at a much smaller scale. This analysis relies on the
assumption that there is sufficient sediment available to form these bays. The sediment budget
analysis suggests that in the first SMP2 epoch there is sufficient sand transport in the offshore
region to feed the sand part of the beach. There is limited shingle material available. As the
Warwick Place Breakwater seeks to retain material on the upper foreshore, it could temporarily
trap material in the formation of the bays. An integral part of the 2009 Scheme is beach
nourishment of approximately 16,500m3 of material in the zone behind the Warwick Place
Breakwater to feed this bay formation to mitigate any adverse impact that the structure would
have in drawing down sediment from other areas of the frontage. As a result of this mitigation,
there will be a minor beneficial effect on the beach, as the beach nourishment benefits the
sediment budget.
The semi-natural historical development of Tywyn as a ‘headland’ in the wider bay also suggests
limited impact from the 2009 Scheme. The existing Bryn-y-mor and Warwick Place defences
already protrude into the naturally curved bay shape, reducing sediment drift potential past these
points. The placement of Warwick Place Breakwater formalises this effect at the least damaging
location leading to a reduction of the impact from minor adverse to neutral.
In addition it is recommended that as part of the ongoing regional monitoring undertaken by CGC
that detailed monitoring of the beaches around the proposed scheme is undertaken to assess the
ongoing alterations to the local sediment transport.
Within the Site – Second SMP2 epoch (20-50 years)
Assessment of Impacts
In the medium term, it is likely that under current sea level rise predictions of between 100-300mm
for Wales that the coastline will continue to retreat at rates similar to or above current rates on the
undefended coastline. At the defended and geologically harder Tywyn frontage, the headland
effect is likely to become more pronounced towards the end of the 20-50 year period. This may
result in a zero drift zone forming at Tywyn as it becomes a definite headland to the bays to the
North and South. Consequently the 2009 Scheme is unlikely to have a significant impact on the
future sediment budget in comparison to the natural processes occurring.
Current predictions also suggest that the changes to wave patterns and water levels will lead to
increased sediment transport. As the shoreline is swash aligned it is unlikely that these changes
will have a significant impact on the coastline unless it led to a particular drift direction becoming
dominant. Historically this has not been observed even with the transgressive nature of the
shoreline. The exception to this is that with predictions suggesting storms will become more
frequent and severe, gross alongshore transport and drawdown events could become more
frequent and greater in magnitude. In both cases the impacts of the 2009 Scheme are likely to be
minimal in comparison to the natural processes, therefore it is considered that there would be a
neutral impact.
Mitigation
Mitigation for the medium term cannot be directly accounted for as part of these works due to the
large uncertainties with respect to the effect on coastal processes at this time scale, however
consideration has been given to the potential future scenarios and the scheme has sought to
allow for adaptive management mitigation approaches. The 2009 Scheme includes the
development of softer edges at the Southern end to ensure a smooth transition into the natural
ENVIRONMENTAL STATEMENT
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coastline, with due consideration of the management practices in the dunes to the South. At the
Northern end, the 2009 Scheme seeks to allow future adaptation to strategic approaches with
other critical defences such as the Network Rail rock armour. The 2009 Scheme is, therefore,
considered to have a neutral impact.
In addition, the regional and detailed monitoring of the performance of the beach will lead to
development of the current management practices and allow response to changes in the natural
system as the evolve over time.
Outside the Site – First SMP2 epoch (0-20 years)
Assessment of Impacts
The ABPmer equilibrium bay analysis (2004b) showed that when comparing the existing situation,
the 2005 Scheme and the natural controls on the coastline that the differences in the coastline
position were all less than 50m, which is a relatively short distance over the 9 km coastline
between Tonfanau and Aberdyfi Bar. In addition the results of this analysis showed that there
would likely be a small increase in the indentation of the bay to the North of Tywyn.
The Atkins (2009) shoreline evolution modelling showed a similar envelope of results, however
under the typical annual conditions, there was an increased build up of material in the Northern
bay. It should be noted that the magnitude of these changes is small and that they would be
unlikely to alter the behaviour of this section of coastline beyond that currently seen or likely to be
impacted by future natural changes, which are typically erosive. Therefore the impact of the
scheme to the North of the site is likely to be neutral.
To the South of Tywyn, the shoreline is essentially free from controlling structures and activities
aside from the nourishment of the dunes at the Southern end of the frontage, which is thought to
be too small a process to have any influence on the overall shoreline alignment, with natural
events being of significantly greater magnitude. In addition the proposed nourishment works to
maintain the sand dunes are for a period of 25 years, beyond which natural processes will be
allowed to resume (unless the SMP2 determines a different policy approach). The dunes are a
minor part of the active sediment budget (acting as a potential source to the rest of the beach as
they erode). Consequently they are unlikely to be altered significantly by the 2009 Scheme. In
addition the impact of the scheme on the principal source of material to the dunes (the intertidal
foreshore) has previously been defined as neutral due to the embryonic headland, the low net
longshore transport rates and the ongoing feed of material from the offshore sand source.
This zone is also the start of the Dyfi geological SSSI which straddles the Afon Dyfi estuary.
According to the previous ABPmer work on embayment formation, the new defences could result
in a very small increase in the indentation of the bay in the vicinity of the Aberdyfi Bar. It should
be noted however that the Aberdyfi Bar is a highly dynamic feature - the actual behaviour of the
coastline cannot be represented by either embayment formation or 1D coastline modelling. The
behaviour of the estuary and subsequently the Aberdyfi Bar will be driven by changes in sediment
supply, river flows and sea level rise. Consequently this is likely to be the significant influence on
shoreline change in this area as the bar forms the control point for the coastline formation and not
the proposed scheme.
The estuary also acts as a barrier to drift with the complex processes interacting at the mouth
which allows the shoreline system to the North and South to be considered as independent units.
Consequently it is considered unlikely that any small changes to the sediment system to the North
will be able to transfer across this barrier and impact to the South. Similarly, any works at Borth
are unlikely to be significant enough to have an impact on the system to the North of the Aberdyfi
Bar. Therefore the impact on the Dyfi geological SSSI is likely to be neutral, either alone or in
combination with works to the South of the estuary.
ENVIRONMENTAL STATEMENT
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60
It is considered that the 2009 Scheme will have the necessary beneficial stabilising effects on
beach morphology in the area between the new structures on the Tywyn foreshore. This
stabilising change will rapidly achieve a new equilibrium state following completion of work, aided
by the inclusion of the beach nourishment. In areas to the North and South of the Tywyn
foreshore the changes occurring are not expected to alter the behaviour of this section of
coastline. In the absence of any such negative coastal formation changes and the small increase
in sediment resources from the beach nourishment, it is concluded that the overall effect on the
sediment budget will be minor beneficial.
Mitigation
It is evident that the 2009 Scheme will formalise the formation of Tywyn as a ‘harder’ headland.
The difference between this, the natural and semi natural headland formation of the harder
geology and the existing defences is harder to ascertain. It is considered likely that the 2009
Scheme will have a neutral impact outside of the site in comparison to the existing situation in the
short term.
It should be noted that as part of the 2009 Scheme it is intended that the placement of beach
nourishment and the small rock structures to the South and North of Warwick Place breakwater
will allow the formation of semi-natural beaches providing a progressive transition between the
Northern and Southern bays and the headland itself, minimising the interruption of littoral
processes.
Outside the Site – SMP2 epoch (20-50 years)
Assessment of Impacts
In the medium term, the effect of the 2009 Scheme is considered negligible in the wider context of
the coastline development. The shoreline alignment will change in future as the hard control
points are subject to erosion. The form of the equilibrium bay will therefore adapt as the Sarn-y-
Bwch is eroded and the ebb delta to the Afon Dyfi evolves in response to sea level rise. Such
changes are likely to occur over relatively long timescales however it is considered likely that in
the medium term this effect will begin to be observed. This would suggest that the effect of the
scheme outside of the site in the medium term will be neutral in comparison to the natural
processes.
Mitigation
Due to the neutral impact of the 2009 Scheme outside the site in the medium term in comparison
to the natural coastal processes, mitigation measures are not considered necessary. It is,
however, recommended that the current monitoring programme is continued to allow adaptive
management to account for effects as and when they are observed.
4.5 Flora and Fauna
4.5.1 Method of Assessment
The baseline data of the flora and fauna of Tywyn and the surrounding area has been obtained
through the following mechanisms:
• Consultation: Consultation has been undertaken with relevant statutory and non-
statutory consultees, as detailed in Section 3
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• Historic Survey Data: An assessment has been made of the data contained in the
Environmental Statement for the 2005 Scheme (ABP, 2005) which included the results
of the following surveys:
- An intertidal biotope mapping survey, including invertebrate sampling at upper,
middle and lower shore locations on the Tywyn sea front (CCW 1997, MNCR 1997)
- A subtidal habitat survey (MNCR, 1995)
- Mid-shore survey carried out in front of Warwick Place in December 2004
• Recent Survey Data: A walkover survey was undertaken on 27 May 2009 of the Tywyn
foreshore for the purposes of this ES, to identify the presence of piddocks and Sabellaria
alveolata (honeycomb worm reef), which were identified in a similar survey undertaken
in 2005
Due to the proximity of the proposed development area to internationally designated sites,
information to inform a HRA has been produced to assess the potential impacts of the scheme on
these sites (see Appendix E).
4.5.2 Baseline Conditions
This section provides information on the baseline flora and fauna conditions within the proposed
area of the works and the immediate surrounding area.
Conservation Designations
A number of designated conservation sites lie within the vicinity of the proposed scheme and are
shown on Figures 9, 10, 11 and 12 in Appendix A.
The proposed works lie adjacent to / in close proximity to the following designated sites, which are
described in the following sections:
• Pen Llŷn a’r Sarnau Special Area of Conservation (SAC) (also referred to as the Pen
Llŷn a’r Sarnau European Marine Site2)
• Craig yr Aderyn Special Protection Area (SPA)
• Dyfi Estuary SPA (also referred to as the Dyfi Estuary European Marine Site)
• Cors Fochno and Dyfi Ramsar site
• Biosffer Dyfi Biosphere
• Broadwater Site of Special Scientific Interest (SSSI)
• Dyfi SSSI
• Dyfi National Nature Reserve (NNR)
Special Area of Conservation (SAC)
SACs are designated under the EC Directive on the Conservation of Natural Habitats and Wild
Fauna and Flora 1992 (92/43/EEC) known as the Habitats Directive. The Habitats Directive is
transposed into UK law through the Habitats Regulations 1994.
2 Where a European site is located below the level of the highest astronomical tide (HAT) they are described
as European Marines Sites (EMS).
ENVIRONMENTAL STATEMENT
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The Pen Llŷn a’r Sarnau SAC is the second largest SAC in the UK, covering an area of
146,023ha. Its boundary extends from the Llŷn Peninsula in the North almost as far as
Aberystwyth in the South. Along the Tywyn frontage, the SAC extends seaward from MLW.
Table 4.5 below lists the interest features of the Pen Llŷn a’r Sarnau SAC as supplied in the
Natura 2000 Standard Data Form for this SAC.
Table 4.5 Pen Llŷn a’r Sarnau SAC Interest Features
SAC Qualifying Feature Interest Features
Annex 1 habitats that are a primary reason for
selection of the site
• Sandbanks which are slightly covered
by sea water at all times of the day
• Estuaries
• Coastal Lagoons
• Large Shallow Inlets and bays
• Reefs
Annex I habitats that are present as a
qualifying feature, but not a primary reason
for selection of the site
• Mudflats and Sandflats not covered
by seawater at low tide
• Salicornia (includes glasswort and
pickleweed) and other annuals
colonising mud and sand
• Atlantic salt meadows (Glauco-
Puccinellietalia maritimae)
• Submerged or partially submerged
sea caves
Annex II species that are present as a
qualifying feature, but are not a primary
reasons for selection of the site
• Bottlenose dolphin (Tursiops
truncates)
• Otter (Lutra lutra)
• Grey seal (Halichoerus grypus)
Special Protection Areas (SPA)
SPAs are designated under the EC Directive on the Conservation of Wild Birds 1979
(79/409/EEC) known as the Birds Directive. The Birds Directive is transposed into UK law through
the Habitats Regulations 1994. There are two SPAs in the vicinity of Tywyn:
Dyfi Estuary SPA
The Dyfi Estuary SPA lies approximately 6km South of Tywyn. Table 4.6 below lists the interest
features of this SPA as supplied in the Natura 2000 Standard Data Form for this SPA.
Landscape Habitats character of this area as cited by LANDMAP:
“The majority of the aspect is planted coniferous woodland with small patches of dry acid heath,
quarry, unimproved acid grassland and wet heath. Habitat condition is un-assessed. There is no
knowledge of any internationally protected habitats or BAP habitats within this aspect area.
However, about 5-10% of the aspect is located within the Cadair Iris geological SSSI. There is no
knowledge of any priority species within this aspect.”
Aspect Area Name: Dune System (Aberdyfi)
Aspect Area Classification: Coastal & Marine Habitats/Coastland/Sand dune (Level 3)
Aspect Area Code: SNPLH395
Landscape Habitats character of this area as cited by LANDMAP:
“The site is dominated by dune grassland, open dunes, shingle above high tide mark, and caravan
site. Sand dunes are internationally protected habitats and BAP habitats. This aspect area
contains high priority BAP habitat and internationally protected habitat. Sand dunes are listed on
Annex 1 of the EC Habitat Directive. Wales hold 60,406 ha of sand dune habitat. Most of the
aspect is located within a SSSI and SAC.”
Visual and Sensory
Aspect Area Name: Tywyn
Aspect Area Classification: Development / Built Land/ Urban (Level 3)
Aspect Area Code: SNPVS003
Visual and sensory character of this area as cited by LANDMAP:
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“Tourist orientated town on coast surrounded by low lying rough pasture with sharp urban edge.
Victorian houses on central promenade, surrounded by modern estates & caravan parks.
Groynes dominant feature of pebbly / sandy beach.”
The key qualities that should be conserved were defined as the heritage and the Victorian
buildings. The need for visual unity was highlighted as was the promenade as in need of
enhancement. The disparate built form should be changed. Other noted qualities were a high
level of night time light pollution and a weak sense of place / local distinctiveness.
Historic Landscape
There are two distinct Historical Aspect Areas which contribute to the wider landscape character
of the study area.
Aspect Area Name: Tywyn
Aspect Area Classification: Built Environment. Settlement / Nucleated Settlement (Level 3)
Aspect Area Code: GWNDDHL101
Historical Landscape character of this area as cited by LANDMAP:
“The ecclesiastical origins of Tywyn probably date back to mid-6th century when Cadfan is said to
have founded a monastery here. The settlement was attacked by the Danes in 963 but
recovered. There are two early funerary stones here. The ''villa de Tywyn'' is recorded in 1283,
and small burgesses are recorded in 1284, when Tywyn had 209 taxpayers. By 1820 the town
comprised just a small cluster of houses around the church, although it was transformed after the
opening of the Cambrian Railway in 1863 with the development of the tourist industry.”
There are no Scheduled Ancient Monuments, Listed Buildings, Registered Parks and Gardens or
Conservation Areas but it is within a Registered Landscape of Historic Interest.
Aspect Area Name: Dysynni valley
Aspect Area Classification: Rural environment/Non agricultural/Reclaimed land (Level 3)
Aspect Area Code: GWNDDHL430
Historical Landscape character of this area as cited by LANDMAP:
“Large area of flat, low-lying land stretching inland from Tywyn up past Abergynolwyn to Tal-y-
Llyn, and Castell y Bere. Much of the area was re-claimed and improved by Corbet
(Ynysmaengwyn estate) after 1788, who transformed inland waste and coastal marshes into
productive land.”
Cultural Landscape
There are two distinct Cultural Aspect Areas which contribute to the wider landscape character of
the study area.
Aspect Area Name: Tywyn
Aspect Area Classification: Influences/Material expressions/Urban/Urban Settlement (Level 4)
Aspect Area Code: SNPCL047
Cultural Landscape character of this area as cited by LANDMAP:
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“An early Welsh settlement which was developed by the Ynysymaengwyn estate in the mid-
nineteenth century and which transformed itself into a small seaside resort with the help of the
Aberystwyth and Welsh Coast Railway from 1863. An important twentieth-century influence has
been the revival of the Talyllyn Railway, from 1951 - originally built to bring slate from
Abergynolwyn to the main line. It was the first 'heritage railway' to be revived by volunteers and
has become a major tourist attraction. The memorial stone in the twelfth-century church is the
earliest example of written Welsh, and dates from between the seventh and ninth century. There
is considerable uncertainty as to its meaning.”
The town was considered to be of high cultural value for its railway associations and for its
medieval origins and in fair condition despite some unsympathetic new development, such as the
supermarket on the site of the goods yard.
Aspect Area Name: Dysynni valley-Afon Fathew-Abergynolwyn-Broad Water
Aspect Area Classification: Influences/Material expressions/Rural/Rural Settlement (Level 4)
Aspect Area Code: SNPCL045
Cultural Landscape character of this area as cited by LANDMAP:
“A multi-period and picturesque area, with a rich legacy of archaeology. Two important estates
were based in this aspect area, Ynysmaengwyn, the foremost 'improving' estate in the county in
the late eighteenth and early nineteenth centuries, and Peniarth, home to an important collection
of texts. Castell y Bere formed the last independent Welsh garrison during the Edwardian
conquest. Mary Jones, who made the journey to Bala to buy a bible which led to the
establishment of the British and Foreign Bible Society, lived all her life in this area. Strong farming
traditions survive here, though many farmers have diversified into tourism. Craig yr Aderyn (area
43) overlooks this area, and the Talyllyn Railway runs through it. Peniarth gardens are Grade 11.”
Baseline Landscape Character Assessment
Key characteristic features of the site of the proposed Scheme:
• Thin, long and linear, sand and pebble beach restricted by the varying hard line of
coastal defence, tracing the coast of the Cardigan Bay
• Flood defences comprising a range of measures, from a formal concrete sea wall to
dilapidated rock armour contained by a bull head rail crib, constructed in different
periods most of which are now in a poor condition
• Timber groynes predominantly in poor condition
• Beach accessed via concrete steps some of which are closed for health and safety
reasons due to the hazardous condition of the bull rail crib defences
• Adjacent to a medium density urban residential and tourist accommodation
neighbourhood
• Car parks and hard pedestrian areas at Victorian Parade with shelters and paddling pool
• Wide textured concrete footpath to North Promenade, with erosion control revetments
with small boulders set in concrete to the adjoining gardens
• A range of architectural styles from a four storey Victorian terrace to modern blocks of
flats along Marine Parade, predominantly residential but with a few business units and a
public toilet block
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• Extensive caravan parks at either end of the site with static caravan holiday homes,
typically finished in green siding
The proposed site is not within or directly contributing to any nationally or locally designated areas
nor near any local historic features. However, within the wider setting there are landscapes of
national and scientific importance including a National Park and other conservation designations.
The local area comprises a medium density, low rise suburban environment with few distinctive or
‘special’ features. However, the proposals must also be considered in the context of the wider
landscape which may be considered to be of good landscape character due to the surrounding
hills and the Dysynni valley.
The proposed site comprises a beach which has regularly been awarded Blue Flag status in the
past and is a popular landscape resource for both the local population and seasonal tourist trade.
However, in its current condition with consideration to the lack of landscape structure and
degraded quality of the public realm the site may be said to be of poor landscape quality,
currently detracting from rather than contributing to the wider landscape character, with significant
scope for positive enhancement.
Sensitivity of Landscape Resources
The sensitivity of the landscape is an important issue in the assessment of the significance of an
effect. This sensitivity is based on the capacity of a landscape to accommodate change, due to a
particular development or land use change, without harm to its character. Landscapes vary in
their capacity to accommodate different forms of development and therefore sensitivity is not
absolute, but is likely to vary according to the existing landscape, the nature of ‘‘the proposed
development’’ and the type of change being considered.
The capacity of the landscape to accommodate change is not directly linked to the value of the
landscape; however, in general terms nationally designated landscapes will always have a greater
sensitivity than those of a local designation due to the importance of their special character and
limited ability to accommodate change without harm. The UK planning system expresses
sensitivity in terms of designations. These designations are as follows:
• International Importance: Very High Sensitivity (i.e. World Heritage Sites)
• National Importance: High Sensitivity (i.e. AONB)
• Regional Importance: Moderate sensitivity (i.e. County Landscape Designation)
• District Importance: Moderate to Low sensitivity (i.e. District and Local Landscape
Designations)
• Local Importance: Low Sensitivity (i.e. non-designated landscape)
It should be noted that a local non-designated landscape may have a great importance to local
people and thus be highly sensitive to change. Other factors to consider in the classification of
sensitivity of landscape resources include:
• The period of exposure to effects
• The degree of exposure to effects
• The function of resource
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• The capacity of the landscape to accommodate change with regards to such factors as
existing land use, the pattern and scale of the landscape, the quality of the landscape
character and the scope for mitigation
The sensitivity of Landscape Resources is classified into three levels: low, moderate and high.
The defining criteria of these terms will necessarily vary according to the landscape and
development being assessed. For the purposes of this assessment, the sensitivity criteria for
Landscape Resources are summarised as follows:
• High – a distinctive or rare landscape where character features are well defined and
where change would likely substantially alter the overall character or function of the area
• Moderate – a definitive landscape of regional where character features are well defined
and where it would likely be tolerant of sensitive changes, though inappropriate
development would likely noticeably alter the overall character of the area
• Low – a landscape where character features are poorly defined with a high tolerance to
change
Sensitivity of Proposed Site
The proposed site is adjacent to a SAC of national importance and 1.5km from a National Park.
Although the site in its current condition can be considered to neither contribute nor detract from
the setting of the National Park, a do nothing scenario may result in direct physical effects on the
SAC in terms of run off and erosion of sand due to the continued deterioration of the coastal
defences.
Thus the role of the proposed coastal defences have a direct relationship with conserving both the
natural and anthropogenic features of the area. The condition of the existing defences detracts
from the character of the local area. The proposals would be likely to alter the character of the
site with both beneficial and detrimental effects. The refurbished / replacement of the timber
groynes, new stepped apron, improved slipways, pedestrian access etc will improve usability and
potential for enjoyment whilst conserving the beach areas and preventing storm damage.
However, the proposed breakwater will have an adverse effect on local character due to its size
despite its contribution to conserving the beach.
Therefore, it is considered likely that the scheme would serve to replace the existing incongruous
man-made features with better quality, sympathetically planned ones. The negative impact of the
breakwater would in terms of pattern and scale be counterbalanced by the proposals to reduce
the size and scale of the defences, thereby conserving the beach itself.
The current poor landscape quality, limited nature of views in from the wider area and the
containment of the site by surrounding buildings and the change in level from promenade to
beach, suggest a high ability to accommodate change. However the potential high footfall on the
beach and pedestrian areas, as well as the adjacent residential and tourist areas significantly
increase the local sensitivity to change. Thus, the proposed development area may be assessed
as having a low sensitivity with a moderate ability to accommodate change without harm.
4.6.5 Baseline Visual Amenity Assessment
Visual amenity of a landscape is determined by considering several factors. Visual appearance is
judged objectively based upon the visual harmony of the wider area, the visual harmony of the site
within itself and the site within the wider area, taking into consideration visually intrusive features
both on and off site and noting features that particularly enhance or detract from the overall
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appearance. Subjectively, visual amenity is judged based upon natural beauty, considering the
overall balance and interest of the site, for example, in terms of colour and diversity, as well as the
pleasure derived from viewing the site.
Visual amenity is rated to include four definable levels of value; these are exceptional, good,
moderate and poor.
• Exceptional – areas of outstanding scenic value, with distinctive features that combine
to give the experience of unity, richness and harmony and create a strong sense of
place. These are landscapes which may be considered to be of particular importance to
conserve on an international or national scale
• Good – areas of pleasing scenic value with a strong sense of place, but occasional
detracting features. These are landscapes with some distinctive features which may be
considered worthy of conservation on a regional or national scale however sensitively
planned change is unlikely to be detrimental
• Moderate – areas of slight scenic value with a weak sense of place and frequent
detracting features. These are landscapes with few distinctive features which may be
considered worthy of conservation on a local scale however there is scope for positive
enhancement
• Poor – areas of no scenic value with dominant detracting features. These are
landscapes with significant scope for positive enhancement
The visual amenity of the proposed development site within the context of the wider area may be
summarised as follows:
• Former Blue Flag beach with prominent incongruous man made features visually in poor
condition
• The sea defences and promenade have limited features of distinction and their evident
deterioration detracts from the local visual amenity of beach and sea
• The site is visually well contained by the sea wall, rock armours, adjacent buildings and
mobile holiday homes; however, the timber groynes are visually prominent from the
beach to the North and South
• Visually balanced with the local area as the mix of construction techniques. and use of
materials within the coastal defences is in keeping with corresponding architectural
styles in the local architecture
• Limited contribution to the landscape character of the wider area
• The deterioration of the quality of the public realm detracts from the visual quality of the
area
The visual amenity of the site for the 2009 Scheme is considered in its current condition within the
context of the wider area. The landscape of the wider area, taking into account local and long
distance views throughout the region, may be said to be of good to exceptional scenic value,
exhibiting a strong sense of place. This is considered to be due to the striking topography of the
valley contrasting with the Cardigan Bay coastline and the harmony and balance of colour and
texture throughout.
Within the wider landscape, Tonfanau quarry is the main detractor from the overall visual amenity.
The railway is especially evident Northwest of the site, however the low lying topography screens
views of local roads.
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Locally, the landscape may be considered to be of moderate baseline visual amenity in
consideration to the urban setting against the context of a wider landscape of good to exceptional
scenic value.
Due to the poor quality of the existing defences and public realm, the development area can be
considered to detract from the scenic value of the Cardigan Bay coast, though is fitting to the
urban context of Tywyn. Therefore the site can be considered to be of moderate baseline visual
amenity.
Long Distance Views
In long distance views, the potential visual impact of the proposed site is very limited as the site is
relatively well contained by the intervening topography and urban development of Tywyn.
However the beach and groynes are visible from Cardigan Bay coastline to North and South of the
proposed site. The sea wall is not visible from distance due to the change in levels and lack of
overlooking receptors.
Local Views (Short Distance)
The poor condition of the seawalls, rock armours, groynes and slipways are visually detracting
from the positive amenity of the beach and sea from local views and from the beach itself. Views
of the proposals will depend on angle of view, change in level and location of receptor, however in
general terms, due to the proximity of the proposals it is appropriate to consider all properties
abutting the beach and promenade as potential visual receptors.
4.6.6 Zone of Visual Influence (ZVI)
The ZVI is the geographical extent to which the development proposals are visible from
surrounding areas. In defining the ZVI, it is possible to identify the potential visual receptors of
any proposed development.
In order to establish the degree to which the site is visible, an initial study was carried out to
assess the extent of the ZVI of the existing features on site and an approximation of the ZVI of the
proposed development. Both were supplemented by checks in the field.
A photographic appraisal of the site and its visual envelope is shown in Figures 19 and 20,
Appendix A. These photographs were taken in early July 2009 using a digital SLR camera with a
50mm lens to represent a perspective similar to the human eye.
Due to the topography of the valley and intervening development of Tywyn, potential views from
the wider landscape of the proposed site are limited. The existing man made features are not
visible, however any development above the height of the existing structures may be visible. The
site is not visible from the town centre and a combination of topography and intervening buildings
screen the site from most of the surrounding neighbourhoods. Properties immediately adjacent to
the site are likely to have views of the proposals; these include residential and business properties
on Marine Parade, Plas Edwards, Bryn-y-mor and Gwynedd Caravan Parks. Users of the beach
within and adjacent to the proposed site, as well as users of the promenades will have the most
immediate views.
The various public rights of way in the area do not experience any views over the site due to
intervening sand banks and railway.
None of these visual receptors will experience a perceptible increased degree of exposure during
winter months due to the limited amount of seasonally affected tree and vegetation cover.
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The prominence of the development proposals will be dependent upon a combination of land use
and topographic factors relative to the position of the visual receptor. It should be noted that while
the size of the site incorporating the scheme proposals is large, the proposals themselves
generally lie below the surrounding street level resulting in a relatively small ZVI. It should be
noted that the height of materials and plant to be stored in the site compounds during the
construction period were unknown at the time of writing and the extents of the ZVI may extend
further than assessed in the ES.
On the basis of the above, the ZVI described previously incorporates the full extent of the visual
envelope considering the site as a whole. Visual receptors have been identified for the entire ZVI
and checked through field survey; however, some that do not have direct views of the proposed
development area are also noted in the list below.
• Residential and business properties along Marine Parade on the first floors and above
have direct views of the proposed site
• Ground floor properties along Marine Parade will have glimpsed views of the proposed
site due to intervening planting, raised planters and shelters but will have views of
construction activities, traffic and the satellite site compound
• Residential properties at Plas Edwards that back on to the promenade
• Public toilet on Marine Parade
• Playground on Marine Parade
• Users of Marine Parade
• Gwynedd Caravan Park
• Bryn-y-mor Caravan Park
• The Cardigan Bay coastline including continued beachfront to North and South
• Users of the Cambrian railway line North of Tywyn, however the perceptibility of change
would be negligible due to the limited period of exposure and existing urban context. As
such this receptor has been scoped out for potential impacts
• Upper ground of Snowden National Park to the East of Tywyn where users will have
glimpsed, partially obstructed views, however the perceptibility of change would be
negligible due to the existing urban context
The Public Rights of Way in proximity to the sight were investigated through field survey and it
was determined that users would not have any exposure to views of the proposals.
Sensitivity of Visual Receptors
The sensitivity of the visual receptors identified is set out in table 4.14 below. The sensitivity of
visual receptors is an important issue in the assessment of the significance of an impact. This
sensitivity is based on the type of receptor, as well as the special nature or the rarity of the view.
Residential properties are considered to have a high sensitivity due to their nature. Additional
factors to consider in the classification of sensitivity of visual receptors include:
• The period of exposure to view
• The degree of exposure to view
• The function of receptor
• The nature of the view and the scope for mitigation
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Table 4.14 Sensitivity of Visual Receptors
Visual Receptor Sensitivity of Receptor
Ground floor properties on Marine Parade High due to nature of receptor
Upper floor properties on Marine Parade. High due to nature of receptor
Public toilet users on Marine Parade. Low due to nature of receptor
Playground on Marine Parade. Medium due to nature of receptor
Gwynedd Caravan Park.
High due to the nature of the receptor.
Note: due to the seasonal nature of the caravan park, the sensitivity reduces to low-medium during off peak periods depending on vacancies
Bryn-y-mor Caravan Park. High due to the nature of the receptor.
Note: due to the seasonal nature of the caravan park, the sensitivity reduces to low-medium during off peak periods depending on vacancies
Users of the beach at and adjacent to the proposed site.
High due to proximity of the proposals
4.6.7 Assessment and Mitigation of Impacts during Construction
During the construction phase, it is anticipated that the construction works, which comprise the
demolition of existing defences and the construction of rock revetments, timber groynes and
breakwaters will result in significant changes in the landcover, character and use of the site.
There will be two site compounds: one at the Northern end of North Promenade between the
promenade and the caravan park; and a satellite compound in the car park at the Southern end of
Victorian Promenade.
Areas of beach will be fenced off with significant levels of vehicle movement and use of heavy
plant machinery.
Construction activities will also result in an increase in vehicular traffic along Marine Parade
including movement of construction vehicles, plant and equipment, as well as any necessary
traffic orders. Delivery Option B would result in greater numbers of HGV vehicle movements to /
from the site compounds and more site traffic than Delivery Option A (see Section 2.2. for more
detail on construction methods and Section 4.8 for detail of the TIAs for both delivery options).
Thus, it is likely that the character of the site would be dramatically altered during the active
phases of construction, due to the nature of a construction site which will form an incongruous
feature in the local established urban area.
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Landscape Impacts
The potential impacts on landscape resources were identified as impacts on:
• Landcover and landform
• Landscape character
• Existing site use
Landcover and Landform
The temporary use of the two site compounds, the storage and use of construction equipment and
vehicles and the delivery of granite rock and other materials for construction of the proposed rock
structures would result in a change in the landscape resources of the site during construction.
These impacts are anticipated as being moderate adverse.
Landscape Character
The proposals would result in a detrimental change in the landscape character of the local area
due to the introduction of construction activities into a reasonably peaceful landscape. These
impacts will be of a temporary nature and considerate working practices and sensitive planning of
the works offer the potential to limit this impact. These impacts would have a limited degree of
exposure on the wider area due to the existing urban nature of the local area and the site’s visual
containment within it.
The impacts on the landscape resources throughout the construction phases using either Delivery
Option A or Delivery Option B (see Section 2.2. for details) are considered to be substantial
adverse given the proximity to the works.
Existing Site Use
The proposals may result in noticeable detrimental change in the land use of the site during
construction due to restricted access and potential inconvenience to the beach and promenade
areas. This is likely to have a subsequent detrimental impact on the tourist trade in the town,
especially if construction is ongoing during peak holiday season.
The impacts on the landscape resources throughout the construction phases using either Delivery
Option A or Delivery Option B (see Section 2.2. for details) are considered to be substantial
adverse given the proximity to the works.
Visual Amenity Impacts
Visual impacts may result from operations throughout construction phases, including construction
plant operations and traffic movements. Table 4.15 sets out the visual amenity impacts of the
2009 Scheme during construction.
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Table 4.15 Potential Visual Impacts during Construction
Visual Receptor Potential Visual Impacts During Construction
Ground floor properties on Marine Parade
All properties would have slight adverse impacts from construction traffic and activity
Central and Southern properties would have moderate adverse impacts as a result of the close proximity of the Warwick Place site compound
Upper floor properties on Marine Parade
All properties would have slight adverse impacts from construction traffic and activity
Central and Southern properties would have moderate adverse impacts as a result of the proximity of the Warwick Place site compound
Public toilet users on Marine Parade
Moderate adverse impacts as a result of the Warwick Place site compound, construction traffic and activity
Playground on Marine Parade
Slight adverse due to the distance from and the view of the Warwick Place site compound and site traffic
Gwynedd Caravan Park
Moderate adverse due to proximity to the proposals and Warwick Place site compound
Construction works undertaken during off peak season would have a slight adverse impact due to limited potential visual receptors
Bryn-y-mor Caravan Park
Substantial adverse due to the proximity of the Bryn-y-mor site compound
Construction works undertaken during off peak season would have a slight adverse impact due to limited potential visual receptors
Users of the beach at and adjacent to the proposed site
Substantial adverse due to proximity of site
4.6.8 Assessment and Mitigation of Impacts Post Construction
During the operational phase, it is anticipated that the scheme proposals would result in both
slight adverse and moderate beneficial changes to the landcover and use of the site due to the
proposed redevelopment of existing structures and the addition of a breakwater. Due to the
nature of the proposals to replace existing structures with similar or a better quality, impacts on
landscape character will be minimal. The likely source of landscape and visual impacts of the
Scheme proposals will be:
• Construction of a new granite breakwater at Warwick Place
• Beach nourishment
• Construction of the Bryn-y-mor Rock Revetment 2m lower than the existing sea wall at
North Promenade
• Reconstruction of Warwick Place slipway
• Refurbishment, replacement and removal of timber groynes
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• Construction of a new stepped apron to the base of the sea wall
The nature of the above impacts are anticipated to be a permanent change in the landscape
character and appearance of the site, and as such will have wider impacts on the overall character
and visual amenity of the area.
The Landscape Institute Guidelines for LVIA state; “The purpose of mitigation is to avoid, reduce
and where possible remedy or offset any significant negative (adverse) effects on the environment
arising from the proposed development”. Mitigation measures fall into two categories:
• Primary measures that intrinsically comprise part of the development design process
• Secondary measures are designed to specifically address the remaining (residual)
negative (adverse) impacts of the final development proposals
The detailed design proposals should consider primary mitigation through layout of buildings and
infrastructure, access, architectural style and colouration of the buildings and building materials,
design of ancillary structures and screen planting.
Secondary mitigation measures should be incorporated into the final design to specifically offset
residual negative impacts of the final development proposals. They also meet the formal
requirement to identify measures for the avoidance or reduction of negative effects. Secondary
measures may include off–site mitigation such as habitat restoration or planting; however, it is
important for these to be effective to demonstrate that long-term control and management is
secured.
The proposals have the potential to result in an increase of footfall and activity to the site as a
result of improved access and amenity thereby offsetting some of the adverse effects likely. As
the site is contained within an existing suburban area of mixed density and style, it is considered
that the negative aspects of the development will be minimised through sensitive site planning,
use of appropriate materials and design.
Primary Mitigation Measures
Due to the coastal conditions and characteristically sparse, low lying vegetation in the area,
mitigation through screening planting is not considered appropriate for the proposals. Therefore,
the detailed design proposals must incorporate primary mitigation through sympathetic selection
of materials in terms of type, scale and colour to the existing wider coastal landscape character
and suburban setting.
The proposed development should be planned to utilise the topography of the site to contain
visually intrusive or incongruous elements, such as the rock revetments, below the level of the
existing sea wall. Replacement elements such as the timber groynes should be similar or smaller
than the existing structures.
Reuse on site of the existing rock from the dilapidated rock armours should also be considered to
minimise removal and importing of material. Wherever possible, lower impact construction
methods should be used to minimise intrusive excavation / filling or change in level.
Secondary Mitigation Measures
Due to the nature of the proposals and the character of the local and wider landscape area,
traditional secondary mitigation measures could be considered for potential future regeneration of
the area.
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The promenades would benefit from improvements to the existing layout and use of space;
introducing high quality paving materials and furniture suites; creating a more vibrant series of
spaces connected by the pedestrian walkway whilst maximising the sea views. Links to the town,
local interests, coastal walks and cycle paths would benefit from integrated wayfinding to aid and
encourage pedestrian footfall and enjoyment. There is also the potential to incorporate
sustainable drainage solutions, such as SUDS (sustainable urban drainage system) paving to filter
and manage site run off.
Landcover Impacts
Due to the nature of the site there is limited existing vegetation that will be affected by the
proposals. The beach will benefit from areas of ‘beach nourishment’. This, along with the
removed, refurbished and replaced timber groynes to prevent erosion and displacement of the
beach itself, plus the ability to reduce the impact of overtopping at Marine Parade by the proposed
rock revetment and breakwater, will help counteract the adverse impacts of their presence. As
such, the effects on the landscape resources in the operational phases are expected to be slight
adverse.
Landscape Character Impacts
The introduction of a breakwater and rock revetments will have a slight negative impact on the
local landscape character due to the introduction of incongruous elements into the area. However,
as a result of the sensitive scheme planning and detailed design, the implementation of the
proposals would also result in a positive change during operation due to the remedying of the poor
condition of the existing coastal defences and improving their functionality and therefore helping to
reduce the impact of future flooding events. Thus, the impacts on the landscape character of the
area throughout the operational phases are expected to be slight beneficial.
Land Use impacts
The proposals have the potential to have a favourable impact on the land use of the site during
operations due to the improved amenity of the beach areas. The new timber groynes and rock
structures, plus the improved beach access and new stepped apron will likely result in increased
footfall to the area in addition to the improved functional ability of the structures themselves. As
such, the effects on the landscape resources throughout the operational phase are expected to be
moderate beneficial.
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Visual Amenity Impacts
Table 4.16 sets out the visual amenity impacts of the 2009 Scheme post construction.
Table 4.16 Potential Visual Impacts Post Construction
Visual Receptor Potential Visual Impacts Post Construction
Ground floor properties on Marine Parade
Properties to the North of Marine Parade would experience no change as their views of the site are screened by the intervening planting on the East side of the adjacent car park
The central properties would have slight beneficial impacts due to the proposed shortened groynes counterbalanced by the moderate adverse impacts of the proposed Warwick Place Breakwater resulting in slight adverse impacts
The properties to the South of Marine Parade would have moderate adverse impacts due to views of the proposed Warwick Place Breakwater
Upper floor properties on Marine Parade
Properties to the North of Marine Parade would have the beneficial impacts of the shortened groynes counterbalanced by the adverse impacts of the proposed Warwick Place Breakwater resulting in slight benefit due to distance from the Warwick Place Breakwater – overall neutral impact
Central and Southern properties would have beneficial impacts of the shortened groynes counterbalanced by the adverse impacts of the proposed breakwater resulting in slight adverse due to proximity of the breakwater– overall neutral impact
Public toilet users on Marine Parade
Moderate adverse impacts due to views of the proposed Warwick Place Breakwater
Playground on Marine Parade
Slight beneficial due to proposed shortened groynes
Gwynedd Caravan Park Users would experience notable adverse impacts due to proximity of the proposed Warwick Place Breakwater counterbalanced by the slight beneficial impact due to refurbished / replaced / removed timber groynes resulting in a slight adverse impact
Bryn-y-mor Caravan Park Slight beneficial due to the refurbished / replaced / removed timber groynes
Users of the beach at and adjacent to the proposed site
Adverse impact of the proposed Warwick Place Breakwater counterbalanced by the beneficial impact of new stepped apron, beach nourishment and the refurbished / replaced / removed timber groynes resulting in a slight beneficial impact
Through considerate design and site planning, the 2009 Scheme may be developed to enhance
both the functionality and the visual amenity of the local area providing an improved beach
environment with coastal management structures that help reduce the impact of flooding and
erosion to the local area and the beach.
As such, through diligent consideration and rationalisation of all the elements of the development
design within the context of the wider landscape, the severity of the overall predicted potential
effects on landscape resources and impacts on visual amenity is anticipated to be of slight to
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moderate benefit. This assessment of the potential impacts is envisaged as applicable to the
site, local surrounding area and wider historic landscape as a whole.
Future regeneration of the Tywyn seaside and promenades offers the potential to significantly
improve the landscape quality and visual amenity of the area. Such works would likely bring about
the additional indirect benefits of raising the public perception and reputation of Tywyn in
particular as a seaside tourist destination.
Implementation of these secondary mitigation measures would likely result in the proposals having
a moderate to substantial beneficial impacts on the local area.
4.6.9 Summary of Landscape and Visual Amenity Impact and Mitigation Measures
The overall impact on landscape and visual amenity during construction is considered to be
moderate to substantial adverse.
Mitigation measures during construction are limited, as screening is unlikely to mitigate these
impacts, due to the low lying nature of the landscape. These impacts are, however, time limited to
the duration of the works.
The overall impact on landscape and visual amenity post construction is considered to be slight
to moderate beneficial.
Mitigation measure to ensure these impacts are not exceeded are:
• Sympathetic selection of materials – type, colour
• Visually intrusive elements (rock structures) to be contained below the level of the sea
wall
• Replacement elements (e.g. timber groynes) to be similar or smaller to existing
structures
• Re-use of existing rock / materials to minimise removal and importing of material
• Use of lower impact construction methods where possible
4.7 Water and Sediment Quality
4.7.1 Method of Assessment
The assessment of the scheme on water and sediment quality has been undertaken by reviewing
existing available data, particularly from EAW. Water and sediment quality have been considered
concurrently due to their interrelationship and ability to affect the quality of one or the other.
4.7.2 Baseline Conditions
The baseline conditions of the existing water and sediment quality are detailed under the following
headings:
• Bathing Water Quality
• Shellfish Water Quality
• Nutrients and Contaminants
• Temperature, salinity and dissolved oxygen
• Suspended solids
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Bathing Water Quality
Tywyn is a designated bathing beach (meaning that it meets mandatory standards set out under
the EC Bathing Water Directive (76/160/EEC)) and as such is monitored every two weeks during
the bathing season (May to September). The concentration of faecal coliforms is variable
throughout the year and is typically highest during the summer months (Environment Agency
2004).
The beach at Tywyn has been classified as ‘excellent’ 65% of the times it has been sampled since
2000 (www.environment-agency.gov.uk). Current figures for 2009 indicate that an ‘excellent’
classification will be achieved for 2009.
Tywyn has also until recently, been awarded a Blue Flag (between 2005 and 2008). The Blue
Flag is an internationally recognised quality mark which means that the bathing water quality has
met certain standards set by the Foundation for Environmental Education (FEE). This includes
water quality standards (which in EU countries must meet with ‘excellent’ status as set by the
Bathing Water Directive), environmental management and the provision of safety and services on
beaches. Tywyn was one of ten beaches in Wales to lose Blue Flag status in 2009. The loss is
considered to be a result of the heavy rainfall during the summer of 2008, leading to a drop in
water quality around the UK coast. Regaining Blue Flag status is considered to be beneficial to
the local tourism industry.
CGC’s Maritime Officer has confirmed that although it would not be possible to suspend works
during the Bathing Waters season, CGC will ensure that the beach is managed in such a way that
the best possible recreational use is achieved during the summer of 2010.
Shellfish Water Quality
There are no designated shellfish waters in the vicinity of the beach at Tywyn. The closest
shellfish waters are located within the Dyfi estuary, at Aberdyfi approximately, 7.5km South of the
proposed site (Food Standards Agency, 2003).
Nutrients and Contaminants
There are no specific data relating to the nutrient and contaminant concentrations in the vicinity of
Tywyn. The 2005 Scheme Environmental Statement (ABPmer, 2005) identified that the National
Monitoring Programme of the quality of UK waters has a sampling location within Cardigan Bay
(National Monitoring Programme, 1998). At this site, nutrient, organic compound and trace metal
concentrations are all defined as low, or very low, and are below Environmental Quality Standards
set by the EAW. There is no evidence that the beach sediment at Tywyn or offshore is
contaminated. In addition, the nature of the existing sediment (sand) does not attract/retain
contaminants. Sand does not act to bind particles together and gets washed easily by waves.
Temperature, Salinity and Dissolved Oxygen
ABPmer (2005) also identified that the EAW undertake monitoring at a site immediately offshore
from the Tywyn foreshore to determine water temperature and the concentrations of dissolved
oxygen and salinity. The water samples are collected from here and other sites along the
coastline between May and September each year. The salinity at the monitoring point ranges
from 21 to 34. Freshwater input from precipitation and estuaries is assumed to have caused
salinities of below 30. The seasonal range in temperature is 9 to 22oC respectively, with the
highest temperatures recorded in July, August and September. Dissolved oxygen at Tywyn has
been measured and categorised as medium (7.5 mg/l) which is above the level at which impacts
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to fish species are observed (Coe et al., 1999). Significant adverse dissolved oxygen sags (typical
of estuarine areas) are not expected at such an open coastal location.
Suspended Solids
Suspended sediment concentrations are also determined at three other EA sampling points
across the wider coastal areas (ABPmer, 2005). The ranges in suspended solid concentration at
these points were 3-37mg/l, 9-33mg/l, and 3-33 mg/l, while the average concentrations were
between 10.1mg/l and 14.9mg/l. The peaks in suspended sediment concentrations were
recorded during the spring in most years between 1998 and 2004.
Sediment Composition and Quality
A number of boreholes were taken on the beach at Tywyn in 2009. The majority of sediment
found at Tywyn is of medium grade sand. Particle size changes with tidal height, with the upper
beach areas being mostly comprised of medium or course gravel. No samples of metal
contamination levels were available to describe the quality of the sediment from this shoreline but
given the particle size grade of sediments and the generally good water quality conditions the
level of contamination is expected to be low (ABPmer, 2005).
4.7.3 Assessment and Mitigation of Impacts during Construction
During construction there is a risk of the release and re-suspension of sediment, which could
increase levels of suspended sediments in the water column reducing the water quality in the
area. This could impact on marine habitats and fish (as described in section 4.5). The activities
that could affect turbidity are:
• Delivery of rock by sea and beaching of boats (Delivery Option A only – see Section 2.3
for details)
• Tracking of plant across the beach
• Excavation for rock structures
• Placement of rocks for the breakwater
• Beach nourishment
• Removal and piling of the groynes
• Seawall/step repairs
Mitigation measures that will be undertaken throughout construction to reduce the risk of sediment
being released are set out in table 4.17. With these measures in place, any sediment released
into the sea is likely to be in small quantities which will dissipate within the water column and
therefore the impacts on water quality in terms of suspended sediments are considered to be
minor adverse.
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Table 4.17 Measures to Reduce Release of Sediments
Activity Mitigation Measure
Tracking of plant across beach Contractor to minimise use of beach area as much as
possible – agree site traffic routes / no-go areas with
CCW / CGC
Excavation for rock structures Excavation will take place at low tide and material will be
stockpiled off of the beach. The material will either be re-
used during the construction or will be removed from site
Placement of rocks for the rock
structures
A geotextile layer will be placed at the base of all
structures before rocks are placed on the substrate. This
will help reduce sediment lost
Beach nourishment To take place after the Warwick Place breakwater has
been constructed so that material released is retained
behind the structure. Recharge will also take place at
mean low water
Removal and piling of groynes To take place at MLW
Seawall/step repairs Concrete will be broken out at MLW and will be stored
above MHW. Concrete repairs will be either pre-cast or
poured into formwork on site. Poured concrete on site
will be done at MLW and will have a setting agent added
to it to increase the rate at which it sets
Delivery Option A
Delivery of rock by sea
Boats to beach as high up the beach as possible.
Barges not to be unloaded 24 hours prior to the date of
sampling
Delivery Option B
Use of protective mats to spread load of exceptionally
heavy plant when operating on the beach – to be
discussed / agreed with CCW / CGC prior to construction
beginning
There is also a risk that the sediment released could contain contaminants, which could reduce
water quality. There is no evidence that the existing beach sediment at Tywyn contains
contaminants. The risk of contaminants from in-situ material is therefore determined to be
neutral.
There is a risk that contaminants could be brought to the site, particularly during the beach
nourishment phase as material will be imported from an external source. Prior to construction,
testing of this material will be undertaken to confirm its suitability specific to this site. Should the
material be determined to contain harmful contaminants, an alternative source would be found.
The risk of contamination released from the imported material is considered to be neutral.
As with many construction schemes near the water, there is also a risk of pollution from spills and
leaks of fuels and chemicals. To reduce the impacts on water quality from pollutants, the following
best practice measures will be implemented:
• Refuelling of vehicles or machinery will take place away from the beach and within a
designated refuelling area. Vessels will return to a nearby port for refuelling
• Vehicles, vessels and machinery will be well-maintained to ensure there are no leakages
of fuel or engine oil
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• The contractor will be required to have an emergency response procedure in the event
of a chemical leak or spill both on land and at sea. All staff on site will be briefed on the
emergency procedures before commencing works
• Oils or chemicals used on land and sea will be stored in suitable bunded containers
• Machinery and equipment stored in the site compound will be locked away at night and
when works are not being undertaken to minimise the risk of vandalism
The adoption of appropriate working practices and following the Environment Agency Pollution
Prevention Guidance 21 will minimise the risk of adverse impacts by encouraging good working
practice and reducing the risk of pollution.
The Contractor will also be requested to include details on the management of pollution risk both
on land and at sea (if using Delivery Option A) in the CEMP.
The potential impact on water quality from spills and leakages from construction plant is therefore
determined to be minor adverse.
Bathing Water Quality
Consideration has been given to the impact of the scheme on the designated Bathing Water
status of the beach and the ability for the beach to regain its Blue Flag status in 2010 and retain it
in 2011. During consultation for this scheme, EAW recommended that no work take place
between the May to September Bathing Water season. The implication is that any reduction in
water quality caused by the construction could reduce the likelihood of the beach meeting Bathing
Waters Directive (BWD) quality standards and hence retaining / regaining Blue Flag status. In
addition, the sampling point is opposite Corbett Avenue, in the centre of the frontage.
EAW advise that mitigation measures are taken wherever possible to reduce any reduction in
water quality. The final decision on works on the beach is the responsibility of CGC, as the beach
manager. Mitigation measures are set out in 4.17 above. In addition, during the Bathing Waters
season the following will also be implemented:
• Where possible, works will be scheduled to take place away from the sampling point
prior to the sampling being carried out to allow time for any increases in turbidity to
dissipate. The contractor and CGC will liaise with EAW to determine sampling dates
• During sampling, the sampling officer must have full and safe access to the sampling
location (the sampling location has been notified to the EU and can not be re-located to
ensure comparative annual sampling is carried out consistently and fairly)
It is determined that with these measures in place, the construction works will have a neutral
impact on Bathing Water quality and will not adversely impact on the ability of the beach at Tywyn
to meet BWD standards or retain / regain its Blue Flag status.
4.7.4 Assessment and Mitigation of Impacts Post Construction
During operation some of the sediment from the beach nourishment behind the Warwick Place
breakwater will be released into the water column from the natural washing and sorting of the
beach recharge material. However, the amount released would be too small to cause any
significant impacts on water quality through turbidity. The impact is therefore considered to be
neutral.
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4.8 Traffic and Transport
4.8.1 Method of Assessment
A Traffic Impact Assessment (TIA) was carried out by Gwynedd Consultancy to assess the
impacts of both rock Delivery Options (see Section 2.3 for details). The results of these TIAs are
set out in this section of the ES. The TIAs and ES only consider the heavy goods vehicle (HGV)
movements associated with the construction of the coastal defences as the level of all traffic using
the proposed route is relatively small.
The following documents were used as guidance in carrying out the TIAs and assessing the
impacts on traffic and transport:
• The Institution of Highways and Transportation. Guidelines for Traffic Impact
Assessment, 1994
• Department for Transport, Guidance on Transport Assessments, 2007
Existing traffic count data was available for three sites along the proposed delivery route (Figure
21, Appendix A):
• on the B4405 at Dolgoch (February 2007)
• on the A493 North of Tywyn (January 2007)
• on the A493 at Rhoslefain (September 2008)
The results of the traffic count are set out in table 4.18, which shows that commercial vehicles,
including the type of which will be used in the delivery of construction materials for the scheme,
represent 10.2%, 5.6% and 7.2% of the 5 day average at each of the count sites respectively.
ENVIRONMENTAL STATEMENT
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Table 4.18 Traffic Count Data for locations along proposed delivery route to Tywyn
Traffic Count on the B4405 at Dolgoch (Feb 2007)
Day Cycles Motorcycles Cars LGVs Commercial
Vehicles Total
Mon 3 4 399 692 121 1219
Tues 3 2 416 643 131 1195
Wed 4 3 402 721 119 1249
Thurs 2 5 337 578 115 1037
Fri 3 4 398 644 117 1166
Sat 7 8 328 600 41 984
Sun 6 14 333 555 15 923
5 Day
Average 3 4 390 656 120 1173
Traffic Count on the A493 North of Tywyn (Jan 2007)
Day Cycles Motorcycles Cars LGVs Commercial
Vehicles Total
Mon 5 11 1437 876 148 2477
Tues 2 7 1374 903 138 2424
Wed 7 6 1512 925 152 2602
Thurs 4 17 1467 895 143 2526
Fri 5 14 1692 1083 140 2934
Sat 6 39 1573 1135 68 2821
Sun 4 30 1165 707 24 1930
5 Day
Average 5 11 1496 936 144 2592
Traffic Count on the A493 at Rhoslefain (Sept 2008)
Day Cycles Motorcycles Cars LGVs Commercial
Vehicles Total
Mon 2 6 817 576 108 1509
Tues 1 6 725 527 110 1369
Wed 1 7 776 534 105 1423
Thurs 1 11 812 583 102 1509`
Fri 1 12 840 572 100 1525
Sat 0 37 836 590 53 1516
Sun 0 51 697 464 28 1240
5 Day
Average 1 8 794 558 105 1466
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4.8.3 Assessment and Mitigation of Impacts during Construction
The proposed route follows the A487 Eastwards on the trunk road network from Porthmadog
before joining the A470 to the South of Gellilydan (Figure 22, Appendix A). At Cross Foxes, to
the South of Dolgellau, the route heads South on the A487 before leaving the trunk road network
and joining the B4405 at Minffordd. The route follows the B4405 through the village of
Abergynolwyn and joins the A496 at Bryncrug before continuing on to Tywyn. The B4405 at
Abergynolwyn passes through the centre of the village, although there is a primary school
adjacent to the B4405 its main access is via a side road and therefore the normal operating of the
school does not directly impinge on traffic on the B4405 (Figure 25, Appendix A). Due to the
restricted carriageway width at the river bridge in the village centre, a priority system has been
established with priority going to Tywyn-bound traffic.
In Tywyn the route turns right at the western end of the High Street on to Idris Villas leading to
Sandilands Road and then to the coast access, where it is proposed to locate the site compound
and storage area. The Warwick Place slipway at the Southern end of Marine Parade is also a
likely destination for material deliveries. Warwick Place would be accessed from the High Street
via Pier Road and Marine Parade passing under the Cambrian Coast rail bridge.
There are a number of locations on the B4405 where the carriageway is less than 5 metres in
width, has a poor horizontal alignment and limited forward visibility. At these locations HGVs
travelling from opposite directions have difficulty passing each other. This could involve vehicles
being stationary for a period of time or reversing on the highway; both of which have significant
safety and traffic disruption implications.
To mitigate some degree of the problem of lorries travelling in opposite directions delaying each
other and other road users, lorries on the return trip to the quarry could be directed to use the
A493 via Llwyngwril and thence to the A470 at Dolgellau, (Figure 24, Appendix A). This
arrangement was successfully employed for the importation of stone for the sea defence of the
Cambrian Coast railway line. This route also has locations where the carriageway narrows and the
alignment is poor, especially through the village of Llwyngwril where it passes in front of
Llwyngwril Primary School. There are issues regarding the carriageway alignment at Arthog,
again due to a narrow carriageway and poor alignment. However, utilising a different route for the
return journey has the advantages of reducing the likelihood of two large vehicles meeting each
other at one of the narrow sections and also halving the number of additional vehicles on the
B4405.
Delivery Option A – delivery of large rock by sea
A calculation was carried out to estimate the number of vehicle trips likely to be required to
transport the approx. 30,000 tonnes of stone and 3,440 m3 of concrete to the site (Gwynedd
Consultancy, 2009) using 6 to 8 wheel 20 tonne capacity wagons. It is assumed that rocks of 6
tonnes or greater will be imported by sea directly to the site (approx. 2/3 total rock requirement).
See Section 2.3 for more detail on the construction methodology.
The greatest number of daily vehicle movements will be in February and March 2010 with 417 and
388 return trips respectively. Using these, maximum values and assuming 20 working days a
month and an 8 hour working day, up to 21 vehicle return trips with vehicles every 22 minutes in
each direction would result. Over the 18 month construction period, more than 10 vehicle trips per
day can be expected over 8 months (between January 2010 – March 2010 and between
November 2010 – March 2011).
The number of HGV movements (as estimated above) was added to the available traffic count
data and the percentage change calculated in table 4.19 below. This shows the scenario in
February 2010, using the B4405 for both outward and return journeys. The percentage change in
commercial vehicle numbers is significant and if permanent would warrant further investigation in
ENVIRONMENTAL STATEMENT
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106
terms of long term environmental considerations. The figures in table 4.19 relate to the worse
case scenario which would only be of one month duration.
Table 4.19 Predicted increase in commercial vehicle numbers
Location
Commercial vehicle numbers from traffic count (5 day average)
Predicted heavy goods vehicle numbers due to proposed scheme
Change in commercial vehicle numbers
Percentage change in commercial vehicle numbers
B4405 at Dolgoch
120 42 162 +35%
A493 Tywyn 144 42 186 +29%
A493 Rhoslefain
105 0 - 0%
Table 4.20 shows the change in vehicle numbers if the B4405 is used for the outward journey and
the A493 is used as the return route to the quarry. This shows the worst case scenario in
February 2010.
Table 4.20 Predicted increase in commercial vehicle numbers
Location
Commercial vehicle numbers from traffic counts (5 day average)
Predicted heavy goods vehicle numbers due to proposed scheme
Change commercial vehicle numbers
Percentage change in commercial vehicle numbers
B4405 at Dolgoch
120 21 141 +17.5%
A493 Tywyn 144 42 186 +29%
A493 Rhoslefain
105 21 126 +20%
The implementation of the project will generate significant temporary impacts to traffic levels along
the route, especially if the B4405 is used for both outward and return journeys.
It is important to note that the traffic figures used in this assessment are for the worse case month
of February 2010, of the remaining 17 months of the project, only the figures for March 2010
approach the February 2010 levels. Therefore the greatest impacts of the project are very short
term and overall the impact is considered to be moderate adverse if the A493 is used for the
return leg of the journey.
Other mitigation measures include:
• Provision of wheel cleaning facilities at the site exits
• That routes are stipulated within any contract
• Ensure that the maximum vehicle size is restricted to 20 tonnes for the transportation of
materials.
• That adequate temporary signing and road markings are placed at the site access and
egress
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Delivery Option B – delivery of all materials by road
A calculation was carried out to estimate the number of vehicle trips likely to be required to
transport the approx. 48,314 tonnes of stone and 3,440 m3 of concrete to the site (Gwynedd
Consultancy, 2009) using 6 to 8 wheel 20 tonne capacity wagons or flatbed lorries.
The greatest number of daily vehicle movements will be in April 2010 and July 2010 with 526 and
474 return trips respectively. Using these, maximum values and assuming 20 working days a
month and an 8 hour working day, up to 26 vehicle return trips with vehicles every 18 minutes in
each direction would result. Over the 18 month construction period, more than 10 vehicle trips per
day can be expected over 14 months (between January 2010 – September 2010 and between
November 2010 – March 2011).
The number of HGV movements was added to the available traffic count data and the percentage
change calculated in table 4.21 below. This shows the worst case scenario in April 2010, using
the B4405 for both outward and return journeys. The percentage change in commercial vehicle
numbers is significant and if permanent would warrant further investigation in terms of long term
environmental considerations. The figures in table 4.21 relate to the worse case scenario which
would only be of one month duration.
Table 4.21 Predicted increase in commercial vehicle numbers
Location
Commercial vehicle numbers from traffic count (5 day average)
Predicted heavy goods vehicle numbers due to proposed scheme
Change in commercial vehicle numbers
Percentage change in commercial vehicle numbers
B4405 at Dolgoch
120 52 172 +43%
A493 Tywyn 144 52 196 +36%
A493 Rhoslefain
105 0 - 0%
Table 4.22 shows the change in vehicle numbers if the B4405 is used for the outward journey and
the A493 is used as the return route to the quarry. This shows the worst case scenario in April
2010.
Table 4.22 Predicted increase in commercial vehicle numbers
Location
Commercial vehicle numbers from traffic counts (5 day average)
Predicted heavy goods vehicle numbers due to proposed scheme
Change commercial vehicle numbers
Percentage change in commercial vehicle numbers
B4405 at Dolgoch
120 26 146 +21.5%
A493 Tywyn 144 52 196 +36%
A493 Rhoslefain
105 26 131 +25%
It is important to note that the traffic figures used in this assessment are for the worse case month
of April 2010, of the remaining 17 months of the project, only the figures for June 2010 and July
2010 approach the April 2010 levels. The greatest impacts of the project are short term. The
ENVIRONMENTAL STATEMENT
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overall impact is considered to be moderate adverse if the A493 is used for the return leg of the
journey, although this impact should be recognised as greater than that for Delivery Option A.
Other mitigation measures include:
• Provision of wheel cleaning facilities at the site exits
• That routes are stipulated within any contract
• Ensure that the maximum vehicle size is restricted to 20 tonnes for the transportation of
materials
• That adequate temporary signing and road markings are placed at the site access and
egress
In addition, given the sustained increase in HGV traffic for most of the 18 month construction
period the following additional mitigation measures should be implemented, in consultation with
CGC Highways:
• Carrying out pre- and post-construction survey of roads at particularly vulnerable / weak
locations
• Notifying residents / businesses at key locations along the route where congestion may
result or where parking of vehicles could impede delivery lorries
4.8.4 Assessment and Mitigation of Impacts Post Construction
Following completion of the works, Marine Parade and the car parks at each end of the road,
directly behind the promenade, will be provided with greater protection from flooding as a result of
the coastal defence improvements. This will maintain the primary vehicular access route to and
from the Tywyn frontage and private properties along Marine Parade whereas previously road
closures occurred as a result of the flood events.
During any maintenance operations, there may also be impacts on traffic (see Section 2.4 for
details of monitoring and operation). These will be short term in duration and of significantly less
duration than the construction impacts. Mitigation measures will, however, be implemented to
reduce any impacts throughout the maintenance works and will include similar measures as for
the capital construction.
Overall, the impact of the scheme on traffic and transport, post construction, has been assessed
to be minor beneficial.
4.9 Recreation and Amenity
4.9.1 Method of Assessment
Baseline conditions were determined through consultation with local organisations and interest
groups. Potential effects were then assessed using past experience and specialist knowledge of
the issues.
4.9.2 Baseline Conditions
The seafront at Tywyn provides a significant, free resource for leisure and is a popular destination
for both local residents and tourists who enjoy using the beach, water and promenade. The
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beach is used all year round and a lifeguard operates during the bathing season which is between
May and September.
A study carried out by eftec (as part of ABPmer, 2003) showed that many local residents visit the
seafront on a regular basis. Almost half of the respondents (48%) visit the seafront on a daily
basis in the spring and summer. This drops slightly to 39% during the autumn and winter. In
addition to local visits to the seafront, it is estimated that there could be up to a further 153,000 to
188,000 tourist visits to Tywyn each year (Gwynedd Council unpublished data in ABPmer 2004a)
and it is likely that a high proportion of these people will visit the seafront.
The beach at Tywyn was awarded a Blue Flag five years in a row from 2004 to 2008, inclusive, as
a mark of the high water quality, environmental management, safety and services available at the
beach. The Blue Flag is an internationally recognised quality mark for beaches.
Beach Recreation
The eftec study (as part of ABPmer, 2003) highlighted the most popular beach activities to be
walking, sunbathing, sitting, picnicking, walking the dog and paddling. Some limited angling also
takes place from the beach. Beach recreation is only possible when the tide is fully or partially
out, as at MHW, the water extends up to the existing sea defences along the full length of the
Tywyn frontage. Visitors also like to use the shelter of the groynes as windbreaks while sitting on
the beach and the concrete steps running the length of the promenade seawall provide seating
areas. There are access steps down to the beach at regular intervals along the promenade.
The existing groynes running the length of the beach and extending between 60 m and 120 m
seaward, have compartmentalised the beach and present an obstruction to easy access along the
beach, particularly the upper areas. Many of the groynes are passable by stepping over them.
However, some of them, particularly towards the Northern end are much higher in relation to
existing beach levels (approximately up to 2m above the beach) and can only be passed safely by
walking around them. The groynes are also in a state of disrepair, with broken / missing timber
planks.
The face of the seawall and its concrete steps are also degraded, with cracks and voids visible
and the underlying steel reinforcement exposed in places. Many of the access steps from the
promenade down onto the beach are in a similar state.
Water Recreation
Watersports are also a popular pursuit at Tywyn, with swimming, boating, surfing and windsurfing
popular, with activity levels increasing during the spring/summer season.
There are four slipways along the frontage which are used for the launching of boats. The
Warwick Place slipway is the largest of the slipways and most frequently used. The other
slipways are situated at the Northern end of the frontage at Bryn-y-mor (at groyne 28 – see Figure
8, Appendix A for groyne layout), Sandilands Road, Pier Road (at groyne 17) and Neptune Road
(between groynes 02 and 03). All four slipways are in a state of disrepair, particularly the Warwick
Place slipway.
To the South of Tywyn is the Aberdyfi harbour. Boats sailing from the harbour can sometimes
seen offshore from the beach at Tywyn.
Promenade Recreation
The promenade extends approx. 1.8km along the Tywyn frontage. Residents and visitors enjoy
walking along the promenade and stopping to look at the sea views.
ENVIRONMENTAL STATEMENT
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During winter storms beach material is often overtops the seawall onto the promenade. Due to
the frequency of this overtopping, CGC does not clear the shingle during the winter months.
Parking Facilities
The town provides good car parking facilities for visitors, with the largest car park situated to the
North of the Warwick Place slipway. Other parking areas along the frontage are at the Northern
end of Marine Parade and at Pier Road. These car parks are affected by wave overtopping and
deposition of sand and shingle during storms, particularly throughout the winter months.
4.9.3 Assessment and Mitigation of Impacts during Construction
During construction there will be some impacts on recreation and amenity due to the presence of
plant and machinery on the beach, vehicles moving to and from site compounds, and the loss of
recreational area on both the beach and the promenade. The 18 month construction will include
the 2010 summer tourism season.
Beach Recreation
The majority of the construction work will take place on the beach or at access points to / from the
beach. There will therefore be areas of the beach that will be restricted for recreational use. To
reduce the impact on recreational use, whilst safeguarding public safety and construction
efficiency, the construction will be phased. Construction activities will be programmed so that only
one section of the beach is undergoing construction at any one time, leaving the remainder
available for recreation. The areas of beach to the North and South of the Tywyn frontage will be
unaffected and will continue to be available for visitors (see Figures 1 and 2, Appendix A for site
location and scheme layout).
Access along the beach will be maintained at all times, although beach users may have to walk
around the phased work areas. However, this is similar to the existing situation whereby the long
groynes create a barrier to alongshore access and beach users have to walk around their
seaward end. The impact on access along the beach is considered to be neutral.
Repairs to access steps will also be phased to ensure that access to the beach is maintained at all
times. The impact on access to the beach is therefore considered to be minor adverse.
Throughout construction, working areas will be clearly defined through the use of signs to inform
the public on working areas and to advise maintaining a safe distance from the works. Signage
will conform to the requirements of the Welsh European Funding Office (WEFO) requirements for
EU funded projects. The contractor is advised to appoint beach marshals to be present on site to
inform the public of plans and progress and to keep them out of dangerous areas where
machinery is working.
Delivery Option A – delivery of large rock by sea
Delivery Option A will require delivery barges to access the beach at high tides in order to offload
rock. At these times, access to the areas of the beach where unloading is taking place will be
restricted. Rock will be delivered as close as possible to areas where it will be required (i.e. the
construction locations) to minimise disruption to beach users (see Section 2.3 for more detail on
the construction methodology).
The impact on beach-related recreation and access is considered to be minor adverse.
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Delivery Option B – delivery of all materials by road
This Delivery Option will require the creation of a stockpile of rock near the Warwick Place
slipway. It will also require the movement of site traffic across the beach to transport rock from the
site compounds at Bryn-y-mor and Warwick Place to the areas where rock structures are being
built. Access to / from the beach will be via the Pier Road and Warwick Place slipways, which
may mean that one or both may not be available for use by the public (see Section 2.3 for more
details of the construction methodology).
Stockpiled rock will be placed in areas where work is being undertaken to contain potential
disruption to discrete areas.
The contractor will endeavour to ensure that either the Bryn-y-mor or Warwaick Place slipway is
available for public use at all times. When this is not possible, the contractor will endeavour to
ensure that both slipways are not available for the shortest time possible.
The contractor will aim to minimise the beach area used by site traffic and routes will be agreed
for site traffic with CGC prior to construction starting. Banksmen will be on site to ensure public
safety is maintained at all times and fences / signage will be erected around stockpiled rock and
site compounds to reduce the health and safety risks to beach users.
The impact on beach-related recreation and access is considered to be moderate adverse.
Water Recreation
Delivery Option A – delivery of large rock by sea
The delivery of rock by sea will require a large barge to be moored offshore and a smaller barge to
deliver rock to the shore (see Section 2.3 for more details).
A notice to mariners will be issued to alert boat users to the construction vessels and signs will be
erected at all three slipways. Signs will also be erected at access points to the beach informing
visitors of vessel movements offshore.
Beach marshals will ensure that swimmers and people engaging in watersports are aware of and
not in the vicinity of approaching vessels. Throughout the Bathing Waters season the contractor
will liaise with lifeguards on duty on the beach.
With these measures in place, the impact on water users is likely to be minor adverse.
Repairs to the slipways will be phased so that only one slipway will be undergoing construction at
any time. The impact on slipway use is considered to be minor adverse.
Delivery Option B – delivery of all materials by road
No vessels are required for Delivery Option B and swimmers and people engaging in watersports
will not be impacted. The impact on water users is likely to be neutral.
This Delivery Option will require the creation of a stockpile of rock near the Warwick Place slipway
and the use of both the Pier Road and Warwick Place slipways for site traffic to access the beach
to / from the site compounds. One or both slipways may not be available for use by the public
(see Section 2.3 for more details of the construction methodology).
The contractor will endeavour to ensure that either the Bryn-y-mor or Warwaick Place slipway is
available for public use at all times. When this is not possible, the contractor will endeavour to
ensure that both slipways are unavailable for the shortest possible time. The impact on slipway
use is considered to be moderate adverse.
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Promenade Recreation
Although there will be some plant and machinery on and moving up and down the promenade, it
will remain open for access throughout the duration of the construction period. Areas undergoing
repairs will have fencing and signs, but will not unduly obstruct the movement of pedestrians along
the promenade. The impact on promenade users is considered minor adverse.
Parking Facilities
The location of one of the site compounds in the car park near Warwick Place slipway will result in
a reduction in the number of available parking spaces. There are, however, two additional car
parks along the frontage, one at the Northern end of Marine Parade and one at Pier Road which
will remain fully open for use. Liaison will be carried out with CGC to agree the number of spaces
taken in the Warwick Place car park for the site compound and signs will be erected in the car
park advising of alternative parking areas. The impact on parking availability is determined to be
minor adverse.
General Construction Disturbance
Visitors will experience some disturbance from the presence of the construction activities through
noise and visual means. Signs will be erected in advance of the construction works as well as
during the works providing information to visitors on the programming and nature of the works.
Contact details will be provided on all information sources in the event of public complaints and or
requests for further information.
It is possible that visitors may be attracted to the area to observe the works taking place, as
previous experience has shown that coastal construction projects generate a high level of local
interest. Further details on noise and visual disturbance are contained in section 4.10 and
section 4.6 respectively. Overall, the impact on recreation and amenity from general construction
disturbance is considered to be minor adverse.
4.9.4 Assessment and Mitigation of Impacts Post Construction
Beach Recreation
Following construction, there will be some loss of beach area available for recreation as a result of
the new rock structures. The total landtake of the new structures is approx 10,000m2 (not
including the area of beach nourishment). This is considered to be a minor adverse impact.
The scheme has been designed to ensure that access along the beach is not significantly
obstructed by any of the new structures. The largest structure is the Warwick Place Breakwater
which will represent an obstacle to access along the beach in the middle and lower shore. Visitors
will not be able to walk around the seaward side of the structure as MLW will meet the base of the
structure. However, the scheme will improve beach access in the upper shore area landward of
the new breakwater by removing the existing groynes at this location. The impact of the Warwick
Place Breakwater on beach access is therefore determined to be minor adverse.
Both the Pier Road Rock Groyne and the South Terminal Rock Groyne will be built at the location
of existing groynes, which will be removed to make way for these new structures. Although both
structures will have a greater land take than the existing groynes they are replacing, they will be
shorter, improving access along the shore. The impact of these structures on beach recreation is,
therefore, considered to be minor beneficial.
The Bryn-y-mor revetment will cause small loss in upper beach area at the Northern end of the
beach. However, there are already six groynes within this area which interrupt access along the
ENVIRONMENTAL STATEMENT
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beach. The extent to which the revetment which will extend seaward is minor in comparison to
the 60m length of these existing groynes. The impact of the revetment is, therefore, considered to
be neutral.
The new rock structures described above will be accessible to the public from the beach at low
tide. There is therefore a risk of injury from people climbing on the structures which could result in
people losing their footing and falling or getting their feet trapped in between the rocks, particularly
as the rocks may be slippery. To mitigate this, signs will be erected advising the public not to
climb on the rocks. This impact is considered to be moderate adverse.
The beach nourishment proposed behind the Warwick Place Breakwater will be at an increased
crest level than the existing beach. The Warwick Place Breakwater will also provide this area with
increased shelter, creating a minor beneficial impact.
The replacement of 27 of the existing timber groynes will provide not only provide a visual
improvement and health and safety improvement to visitors, but they will be made significantly
shorter, reducing their existing obstruction to beach access and improving the openness of the
beach for recreation. The new shorter groynes will be approximately 30m long, in comparison to
the existing groynes which extend seaward between 60m and 120m. In addition, the groynes will
be approximately 1m lower in height than the existing ones, reducing visual intrusion but still
enabling people to use them as windbreaks. The shortening and refurbishment of the groynes will
have a moderate beneficial impact on alongshore beach access.
The repairs to the stepped concrete seawall will enhance the seating areas for visitors and the
improvements to the beach access steps will improve access and reduce the risk of accidents.
This is considered a moderate beneficial impact.
Water Recreation
The location of all the new rock structures will not impact on existing water sports such as surfing,
windsurfing and sailing/boating activities as these occur further offshore, beyond the MLW mark.
As described in section 4.4, the scheme will not alter offshore wave patterns. The impact on
watersports is therefore neutral.
The scheme could encourage swimming around the Warwick Place Breakwater during high tides.
Breakwaters are known to generate eddies and strong currents. Although there will be some
secondary currents generated, these are unlikely to be strong enough to pose a risk to swimmers
and the impact is assessed to be neutral.
There is a risk that recreational and commercial boats could collide with the new rock structures,
particularly at night or during strong current and wave conditions. Navigational aids will be
provided on the seaward extent of the Warwick Place Breakwater, Pier Road Rock Groyne and
South Terminal Rock Groyne to reduce this risk in consultation with Trinity House. The impact is
assessed to be minor adverse.
The repairs made to all three slipways will improve the launching and recovery of boats. Although
the Warwick Place Breakwater and beach nourishment will be constructed in front of the Warwick
Place slipway, these elements of the scheme will not restrict the use of the slipway. Both the Pier
Road and Warwick Place slipways will benefit from increased shelter from the new rock
structures. Overall, the impact of the scheme on the three slipways is considered to be minor
beneficial.
Promenade Recreation
The repairs made to the promenade will enhance the amenity experience of visitors using the
promenade both visually and in terms of health and safety. The new structures will reduce the
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frequency and severity of wave overtopping and will reduce the disruption to access caused by
sediment overtopping the seawall. The new viewing platform at Pier Road will provide an amenity
asset, allowing visitors to enjoy the seaviews from a dedicated viewing area (see Section 4.6 for
details on the landscape and visual amenity impacts). Overall, the scheme will have a moderate
beneficial impact on the use of the promenade by visitors and local residents.
Parking Facilities
Following construction, the site compound will be removed from the car park adjacent to the
Warwick Place slipway and the parking spaces reinstated to their existing condition. As with the
promenade, the scheme will reduce wave overtopping and disruption to parking from sediment
carried by waves into the car park, creating a minor beneficial impact.
4.10 Noise
4.10.1 Method of Assessment
A qualitative assessment of potential impacts has been made, based on professional experience
and judgement. This section only considers the impact of noise on people. Impacts on birds and
fish are described in section 4.5.
4.10.2 Baseline Conditions
Background levels of noise include those generated by local traffic (including the Cambrian line
railway, which runs through the town centre, approx 1km from the seafront) and sounds
associated with coastal settlements (wind, waves, birds and amenity users (including dogs)).
Immediately behind the promenade and running the full length of the frontage are residential
properties, as well as two caravan parks. To the North of Tywyn are open fields, with the next
nearest settlements being a sewage treatment plant situated approx 350m to the North and the
village of Tonfanau, approximately 3km away (to the North of the Dysynni). The nearest
settlement to the South of Tywyn is Ynyslas at the mouth of the Dyfi, 5km South of Tywyn.
For reference, noise level is measured in decibel units (dB); a quiet office would have an average
sound level of 55dB and a busy street 80dB. Coast protection work currently taking place at
Aberaeron on the Welsh coastline has recorded peak noise levels of 70dB (at source), but it is
recognised that noise levels are highly site specific.
4.10.3 Assessment and Mitigation of Impacts during Construction
During construction, noise will be generated from the works taking place on the beach,
promenade and from the site compound. Noisy activities will include the general movement of
plant and machinery (including excavators, bulldozers and dump trucks), delivery of rocks by road
or marine vessels, the placement of rocks, piling for the timber groynes, beach nourishment and
delivery of other smaller materials by road. It is anticipated that the loudest activities will be the
placement of the rock for the rock structures and the piling for the groynes.
During the piling works for the replacement groynes, two piling methods will be used; hammering
and vibro-piling. The timber piles will initially be hammered into the ground. Hammering creates
more noise than vibro-piling but the initial hammering action gets the timber piles securely pushed
into the underlying sediment. They can then be vibro-piled to the correct depth. Although piling is
often considered a particularly noisy activity, this is often in relation to steel piles and piling into
hard ground. Piling the timber piles into the softer beach sediment will generate much less noise
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than steel piling into hard ground would. More detailed information on the construction
methodology can be found in Section 2.3
Local residents living in properties immediately behind the promenade and near the site
compounds at Bryn-y-mor and Warwick Place will be most affected by the construction period as
they will directly face the main working areas. During the spring/summer tourism season, the
caravan parks at Bryn-y-mor and Neptune Road will also be impacted by construction noise as
they also face directly on to the back of the beach. Increased noise levels will also be
experienced by beach and promenade users.
The contractor will reduce noise impacts by phasing the work along the beach so that only one
section of beach is undergoing construction at any one time. This will limit the area in which noise
will have an impact.
Throughout construction, the contractor will implement best practice methods to reduce noise
levels. Noise will be minimised by adherence to relevant British Standards, including
BS5228:1997, Part 1, Annex B ‘Noise Control and Open Sites’. All machinery will be well-
maintained and fitted with appropriate muffling or silencing equipment and turned off when not in
use. The Contractor will be expected to include provisions for these mitigation measures.
Information on working hours and the duration of the construction period will be provided to local
residents and visitors in advance of the works as well as throughout the construction period. This
will include the provision of notices and signs along the promenade. Contact details will be
provided on all information sources in the event of public complaints and or requests for further
information. The Contractor will also erect signs around the site providing details of the work as
well as contact names and numbers. Beach marshals will also be on site to answer questions
from the public.
Consultation with the CGC’s Environmental Health Officer will be undertaken prior to construction
to confirm acceptable working hours and any other measures required to minimise disturbance to
the public.
The settlements to the North and South of Tywyn are a significant distance away from the works
to experience any significant noise disturbance. The sewage treatment works to the North will
experience some noise disturbance, but due to the industrial nature of the premises, the impacts
are not considered significant.
Delivery Option A – delivery of large rock by sea
The delivery of rock by sea will involve the delivery and offloading of rock from the barge over a 24
hour period, as the barge can only deliver rock to the beach on the high tides. These 24 hour
working periods will be intermittent and will last for periods of approx. 7 days with unloading
activity taking approx. 3 hours. During night-time working hours (between 7pm and 7am),
reversing sirens will be replaced with hissers and workers will use either cars or light goods
vehicles to/from the site.
All other deliveries and all construction activities will take place only during daylight hours (7am –
7pm) (see Section 2.3 for details of construction methods).
With these mitigation measures in place, the impacts of noise on local residents and visitors are
considered to be moderate adverse.
Delivery Option B – delivery of all materials by road
The movement of HGVs through the town to deliver rock and other materials will generate noise,
as will the tipping / unloading of rock at the site compounds and the loading of site vehicles.
Tipping of rock from delivery vehicles will generate a significant amount of noise. This could occur
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at least 10 times per day (and peak at over 20 times per day) whilst rock is being delivered, which
will extend throughout most of the construction period.
Residents in properties along the proposed traffic route to / from the site will be impacted by the
movement of construction vehicles to and from the site, experiencing over 10 vehicle movements
per day for most of the construction period. Residents (permanent and temporary) close to the
site compounds will also be impacted by the movements of site traffic to / from the site
compounds. Site traffic movements will be approx. three times greater under Delivery Option B
than Delivery Option A. More information on the traffic impacts is in Section 4.8.
To reduce the impacts of noise on local residents and visitors, construction and delivery activities
will be restricted to between the hours of 7am and 7pm (see Section 2.3 for details of construction
methods).
Given that these impacts could extend for the majority of the construction period, the impacts of
noise on local residents and visitors are considered to be major adverse.
Noise impacts could be reduced to moderate adverse if delivery lorries were unloaded by
excavators picking up rocks individually instead of lorries tipping their load. This may, however,
increase the length of time it takes to deliver and unload rock, increasing other impacts on local
residents, such as from traffic nuisance, vehicle emissions and visual impacts.
4.10.4 Assessment and Mitigation of Effects Post Construction
Following construction there will be no impacts to noise levels. The impact is therefore considered
to be neutral.
4.11 Air Quality
4.11.1 Baseline Conditions
Air Quality describes the levels of atmospheric pollutants, particulate matter and odour. Local
Authorities, under the Environment Act 1995, have a statutory duty to review and assess air
quality on a regular basis. CGC produces annual Air Quality reports on all air quality activities
within which are highlighted Air Quality Management Areas (AQMAs). These are areas suffering
the worst air quality in the district, followed by the setting out of priority work items for the year
ahead. No AQMAs were declared in the most recently available 2007 report for Gwynedd.
There is no primary industry and limited traffic in the area. The location of the works is set on the
coast and is very exposed and it is expected that air quality is very good.
4.11.2 Assessment and Mitigation of Impacts during Construction
Air quality impacts will be temporary and restricted to the immediate vicinity of the site. The key
sources of these impacts will be vehicle emissions and sand from the movement of plant and
materials around the site as well as from the excavation, rock placing and beach nourishment
operations.
Vehicle emissions will be minimised by the contractor ensuring that all vehicles and machinery are
well-maintained, and that engines and machinery are not left running unnecessarily when not in
use. The contractor will also be responsible for ensuring that all public roads, during the delivery
of light materials, are kept free from mud and dust, which can be achieved by the following actions
where necessary:
• Washing wheels of vehicles when leaving the site
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• Ensuring vehicles are kept clean
• Damping down roads and construction areas if conditions become dry and sandy
Delivery Option A – delivery of large rock by sea
The impact on air quality during construction is considered to be neutral.
Delivery Option B – delivery of all materials by road
The greater number of HGVs required to deliver materials and the need for more vehicle
movements on site (between site compounds and construction areas) will result in more vehicle
emissions and the potential to stir up more sand from the beach than under Delivery Option A.
There are no additional mitigation actions to counter these impacts. The impact on air quality
during construction is considered to be minor adverse.
4.11.3 Assessment and Mitigation of Impacts Post Construction
There will be no impacts on air quality as a result of the long term operation of the scheme,
including during any maintenance works. The impact on air quality post construction is
considered to be neutral.
4.12 Historic Environment
4.12.1 Method of Assessment
A review of the Archaeological Assessment undertaken by Gwynedd Archaeological Trust (GAT)
as part of the 2005 Scheme EIA was carried out see Appendix H for a full copy of the report). A
high level rapid assessment of the following resources was also performed, with the specific aim
of identifying any new information which may have been published since the GAT Assessment
was completed in 2004;
• GAT Historic Environment Record
• Core Archaeological Record Index for Wales
• Royal Commission On The Ancient and Historical Monuments of Wales
• National Monuments Record of Wales.
GAT were consulted during the drafting of this Environmental Statement. Their responses are in
Appendix C.
4.12.2 Baseline Conditions
Previous studies (ABPmer 2004, GAT 2004) have found that there are relatively few
archaeological or historic environment features in the general area of the scheme in particular and
Tywyn seafront in general.
The GAT Assessment (see Appendix H) identified thirteen archaeological/historic interest
features within their 1km survey area, which are listed below in Table 4.23.
The features are assigned one of five categories of importance, A-E.
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A: National Importance
B: Regional or County Importance
C: District or Local Importance
D: Minor or Damaged Sites
E: Sites needing further investigation
Of the thirteen interest features identified within the GAT survey area only three (features 6, 7 & 8)
are known to be within the study area:
• Bronze Spearhead findspot (feature 6)
• Bronze Age Crematorium Urn (feature 7)
• Tywyn Promenade (feature 8)
In addition, two other features (features 9 & 10) may extend in to the study area or be at risk
during the construction of the scheme:
• Ancient peat beds (feature 9)
• Turbary (feature 10)
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Table 4.23 Archaeological and Historic Interest Features within a 1km radius of Tywyn
Feature No. Feature Name OS Grid
Reference
Period Category
1 Afon Dysynni Entrance
Wall
SH 5614 0320 20th Century C
2 Dysynni Marshes Sea
Bank
SH 5724 0160 –
SH 5670 0260
19th – 20
th
Century
C
3 Afon Dysynii Low Level
Tidal Gate and Culvert
SH 5718 0188 19th Century C
4 Afon Dysynii Low Level
Outfall
SH 5706 0185 19th Century C
5 Cambrian Coast
railway embankment
SH 5734 0154 –
5670 0270
19th Century C
6 Bronze spearhead
findspot
SH 5770 0095 Early first
millennium BC
B
7 Bronze Age
Crematorium urn
SH 5800 0000 Early second
millennium BC
B
8 Promenade, Tywyn
sea-front.
SH 5792 0010 –
5775 0058
19th Century B
9 Ancient peat-beds SN 5810 9960 Prehistoric B
10 Turbary SN 5818 9932 18th – 19
th
Century
B
11 Afon Dyffryn Gwyn
Outfall
SN 5825 9935 19th – 20
th
Century
C
12 Afon Dyffryn Gwyn
Tidal Gate and Culvert
SN 5835 9940 19th – 20
th
Century
C
13 2nd
World War coastal
defences, Pill Box
SN 5853 9886 20th Century B
Source: GAT Archaeological GAT Assessment, 2003
4.12.3 Assessment and Mitigation of Impacts during Construction
The assessment of the impacts of the scheme is separated in to impacts within the study area and
impacts adjacent to the study area.
Impacts Within the Study Area
No significant features of heritage interest that could be directly affected by the scheme were
identified in the study area.
There are three features of interest in or near Tywyn (features 6, 7 & 8) but they are not on the
foreshore itself. GAT concluded that features 6 and 7 were wrongly attributed to the Tywyn
frontage and that they were in fact discovered some distance from the study area. Therefore, it is
unlikely that the proposed scheme will result in any impacts on these features.
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It is possible that the construction of the scheme could have a negative impact upon the
promenade since heavy plant will be operating close to the promenade and may be required to
traverse directly over it. Such actions could result in damage occurring to the promenade. In
order to reduce the potential impacts a suitable construction methodology will need to be agreed
by the contractor with CGC / GAT (e.g. use of banksmen during operation of heavy plant).
A summary of the potential impacts upon features 6, 7 and 8 as well as GAT’s recommended
mitigation measures is presented in Table 4.24.
Table 4.24 Summary of Effects within Study Area and Mitigation Measures
Feature
No.
Feature Name Nature of Impact Impact Mitigation Measures
6 Bronze spearhead
find-spot
N/A Neutral None Required
7 Bronze Age
Crematorium urn
find-spot
N/A Neutral None Required
8 Promenade,
Tywyn sea-front
Direct Damage
from heavy
machinery on or
adjacent to the
promenade.
Collision of
plant/machinery
with the
promenade
Minor
Adverse
Watching Brief and
agreement of suitable
construction methodology
with contractor
Source: GAT Archaeological GAT Assessment, 2003
GAT suggested that the peat beds and associated turbary to the South of the study area may
extend beneath the surface of the sand in to the study area. It was also recognised that in the
area directly in front of the promenade any peat beds may have already been eroded following the
promenade’s construction (GAT 2004). The results of trial pit investigations commissioned for the
2005 Environmental Statement showed most of the pits (especially those at Bryn-y-mor and Pier
Road) contained only sand and or cobble/shingle in the top 1.5 to 2m of the beach within which
the toe of the structures is likely to be placed (sediment below this depth will be unaffected). At
Warwick Place a clay layer was recorded at around 1 – 1.1m below the surface but no further
information for sediment below this depth was available.
Further ground investigations carried out in summer 2009 for the 2009 Scheme also showed no
evidence of peat beds within the study area. The results of these investigations will be made
available to GAT to determine if they believe there are any historically important peat deposits in
the area. Potential impacts and possible mitigation actions that GAT may consider necessary,
after viewing the 2009 ground investigation results are presented in Table 4.25.
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Table 4.25 Summary of Effects on Peat Deposits within Study Area and Mitigation Measures
Feature No.
Feature Name Nature of Effect Impact Mitigation Measures
9 Ancient peat beds Direct damage from plant/machinery when excavating and from tracking of lorries over exposed or shallow peat deposits
Minor Adverse
Trial Pit excavations (awaiting results) Watching Brief and detailed recording Use of protective mats to spread load of exceptionally heavy plant when operating on the beach (if peat deposits are found at any stage in the construction) Contractor to minimise area of beach for vehicle movement
10 Turbary Direct damage from plant/machinery when excavating and from tracking of lorries over exposed or shallow peat deposits
Minor Adverse
Trial Pit excavations (awaiting results) Watching Brief and detailed recording Use of protective mats to spread load of exceptionally heavy plant when operating on the beach (if peat deposits are found at any stage in the construction) Contractor to minimise area of beach used for vehicle movements
Source: GAT Archaeological GAT Assessment, 2003
With these mitigation measures in place the residual impacts are considered to be minor
adverse.
Impacts Adjacent to Study Area
The construction of the scheme will involve the movement and use of heavy plant on the
foreshore. If the peat beds or turbary to the South of the study area are exposed or only slightly
covered by sand, significant damage could be caused by machinery or plant crossing over them.
It is recommended that all machinery / plant be limited to the study area and do not work or move
across any area South of groyne 1, in order to minimise potential impacts to any nearby peat
deposits. A summary of the potential impacts and suggested mitigation measures is presented in
Table 4.26. With these mitigation measures in place the residual impacts are considered to be
minor adverse.
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Table 4.26 Summary of Effects Adjacent to Study Area and Mitigation Measures
Feature
No.
Feature Name Nature of Effect Impact Mitigation Measures
9 Ancient peat beds Direct damage from
plant/machinery
tracking over
exposed or shallow
peat deposits
Minor
Adverse
Plant/machinery limited to
study area
10 Turbary Direct damage from
plant/machinery
tracking over
exposed or shallow
peat deposits
Minor
Adverse
Plant/machinery limited to
study area
Source: GAT Archaeological GAT Assessment, 2003
4.12.4 Assessment and Mitigation of Impacts Post Construction
The assessment of the potential impacts following construction of the scheme has been separated
in to impacts within the study area and impacts adjacent to the study area.
Impacts Within the Study Area
The purpose of the scheme is to provide improved coastal protection to the Tywyn frontage and
reduce erosion directly in front of the promenade. One impact of the scheme following its
construction will be the defence of the Tywyn frontage which has been assessed as moderately
beneficial. Table 4.27 summarises the impact of the scheme during operation upon the features
known to be within the study area.
Should additional trial pit investigations find peat deposits within the study area, the increased
size/depth of the Tywyn beach/foreshore, resulting from the scheme, will provide additional
protection to the deposits from erosion. This should prevent any potentially valuable
archaeological records from being washed away.
Table 4.27 Summary of Effects and Mitigation Measures within Study Area
Feature
No.
Feature
Name
Nature of Effect Impact Mitigation Measures
6 Bronze
spearhead
find-spot
N/A Neutral None required
7 Bronze Age
Crematorium
urn find-spot
N/A Neutral None required
8 Promenade,
Tywyn sea-
front
Provision of
protection from wave
energy. Reduction in
risk of
subsidence/collapse
Moderate
beneficial
None required
Source: GAT Archaeological GAT Assessment, 2003
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Any future maintenance works (e.g. beach recharge / re-profiling) may require the tracking of
heavy plant across the Tywyn foreshore which could cause disturbance to peat deposits buried
beneath the surface of the sand. The use of protective mats (e.g. Eve Trakway) could be used to
spread the load and reduce the disturbance to underlying peat.
A summary of the potential impacts to peat deposits within the study area during operation and
suggested mitigation measures is presented in Table 4.28 with these mitigation measures in place
the residual impacts are considered to be neutral.
Table 4.28 Summary of Effects and Mitigation Measures within Study Area
Feature
No.
Feature Name Nature of Effect Impact Mitigation Measures
9 Ancient peat beds
Accumulation of beach
material over already
buried peat deposits
Direct
damage/disturbance from
plant/machinery tracking
over buried peat deposits
during maintenance work
Neutral Use of protective mats to
spread load of exceptionally
heavy plant when operating
on the beach (if peat
deposits are found at any
stage in the construction)
10 Turbary Accumulation of beach
material over already
buried peat deposits
Direct
damage/disturbance from
plant/machinery tracking
over buried peat deposits
during maintenance work
Neutral Use of protective mats to
spread load of exceptionally
heavy plant when operating
on the beach (if peat
deposits are found at any
stage in the construction)
Source: GAT Archaeological GAT Assessment, 2003
Impacts Adjacent to Study Area
The results of numerical modelling (Section 4.4) have shown that the scheme is not predicted to
have an impact at other points along the coast and in light of this it is unlikely that there will be
impacts on archaeological interest features outside of the study area during operation or post
construction. Impacts are, therefore, considered to be neutral
4.13 Navigation
4.13.1 Method of Assessment
Information on navigation in the waters offshore of Tywyn and the surrounding area has been
obtained by reviewing the ES carried out for the 2005 Scheme (ABPmer, 2005). No major
navigation interests were identified in the review.
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4.13.2 Baseline Conditions
Very little vessel activity takes place offshore of the Tywyn frontage. This is due to the exposed
nature of the shoreline, making it difficult to launch boats from the three available slipways
(Warwick Place, Pier Road and Neptune Road), particularly when the tide is in. Of the activity that
does take place, this takes the form of small leisure boats and jet skis. Approximately 8-10 jet skis
are regularly used on the Tywyn sea front has been established to keep jet skis and boats
separate from swimmers and other water users (ABPmer, 2005).
There are also very few fishing vessels navigating offshore. As described in section 4.14, a single
fishing boat (14-16 feet in length) occasionally launches from available slipways (ABPmer, 2005).
There is also some local fishing activity off the reef to the North of Tywyn.
Approximately 5km to the South of tywyn is Aberdyfi harbour. CGC is the Harbour Authority (as
empowered by the Aberdyfi Harbour Empowerment Order 1972) and all activities within the
harbour area are controlled by the CGC Harbour Master (CGC, 1998). Information described
throughout this section with respect to the number and type of vessels that use the harbour at
Aberdyfi and operate in the Afon Dyfi and adjacent coastal areas were supplied to ABPmer (2005)
by the Assistant Harbour Master and are set out in table 4.29.
Table 4.29 Occupancy Details for Aberdyfi Harbour
Year Personal Watercraft Power Boats Annual Moorings Visiting Yachts
1995 N/A 40 102 171
1996 N/A 38 95 192
1997 N/A 41 105 220
1998 41 37 101 124
1999 41 48 110 135
2000 68 67 99 130
2001 57 77 110 140
2002 32 73 102 90
2003 50 89 104 125
Average 48 57 103 147
Source: ABPmer, 2005
Most vessels at Aberdyfi are visiting yachts and boats owned by people with annual moorings.
Since 1998, the number of visiting yachts has remained relatively constant at approximately 130,
with a dip in 2002. The number of annual moorings has remained constant over the period 1995
to 2003 (ABPmer, 2005). In terms of other water users, jet skis are launched from the Aberdyfi
harbour slipway on a daily basis and the Aberdyfi Sailing Club has around 20 boats of varying
size. Typically there are approximately 20 jet skis being launched on a Bank Holiday (ABPmer,
2005). The majority of these boats operate within the Afon Dyfi, rather than the open coast, and
the estuary is particularly busy in July and August due to the annual ‘Dinghy Fortnight’ event and
summer holidays (ABPmer, 2005).
The number of fishing vessels at Aberdyfi is very low in comparison to other harbour users. There
are only five fishing vessels and only one of these is regarded as being a full time commercial
operator, along with 8 day boats that are privately owned and used for sea angling (ABPmer,
2005). The Aberdyfi and Borth Lifeboat Stations also operate offshore in the area around Tywyn.
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4.13.3 Assessment and Mitigation of Impacts during Construction
Delivery Option A – delivery of large rock by sea
Delivery Option A will require the presence of vessels in the water immediately offshore of the
Tywyn frontage during the delivery and offloading of the rock, which is estimated to take
approximately 3 months. More detail on the delivery of rock and construction method is contained
in Section 2.
The delivery of the materials by sea could impact on navigation routes for both recreational users
and fishermen. However, due to the limited number of vessels that will be used (main ship, barge
and tug) the increase in vessels in the water will be minimal. In addition, the waters in the vicinity
of the works are not regularly used by vessels.
Nevertheless, there will be a need to manage vessel movement to ensure that any risks of
collision or accidents are minimised. The shipping contractor will be responsible for vessel
management and will be required to have an appointed pilot (or ‘Barge Master’) on the delivery
vessel that will oversee and direct all barge movements. The Barge Master will be required to
liaise with the CGC Harbour Master with whom working practices will be agreed in advance. A
Notice to Mariners will also be issued.
Efforts will also be made to minimise the disruption to boat users launching craft from the slipways
(including during the movement of plant on the beach) and to ensure that navigation in the
nearshore zone remains safe (see Section 4.9 for impacts on water recreation).
Given the implementation of the required vessel management measures as well as the placement
of appropriate shoreline signage and the spatial extent and location of the proposed structures it is
expected that the proposal will have a minor adverse impact on navigation immediately offshore
of Tywyn. Impacts further South in the vicinity of the Aberydyfi Harbour and on lifeboats are
considered neutral.
Delivery Option B – delivery of all materials by road
The impact on navigation is considered to be neutral (see Section 4.9 for impacts on water
recreation).
4.13.4 Assessment and Mitigation of Impacts Post Construction
Following construction, the position of the Warwick Place Breakwater could pose a navigational
hazard through the risk of vessel collisions with the structure. However, the structure is located
just above MLW and as it will only be partially submerged at MHW will not be in the direct path of
vessels. Navigation marks will be positioned on the seaward edges of the Warwick Place
Breakwater, the Pier Road Rock Groyne and the South Terminal Rock Groyne to reduce any
risks. These are likely to comprise a green pole surmounted with a green conical shaped top
mark. The navigational aid will be agreed in consultation with Trinity House. Given the location of
the rock structures and the navigation aids proposed the scheme will have a neutral impact on
navigation.
Although the Warwick Place Breakwater and beach nourishment will be constructed in front of the
Warwick Place slipway, these elements of the scheme will not restrict the launching of boats from
this slipway. The imported beach sediment will be similar to existing therefore not impacting on
the ability for boats to be manoeuvred to the water’s edge. Both the Pier Road slipway and the
Warwick Place slipway will also benefit from increased shelter from the Pier Road Rock Groyne
and Warwick Place Breakwater respectively. Overall, the impact of the scheme on navigation
from the beach is considered to be minor beneficial due to the improved shelter offered by the
scheme. The scheme will not impact (neutral) on existing RNLI navigation routes.
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4.14 Commercial and Recreational Fisheries
4.14.1 Method of Assessment
Information on fisheries offshore of Tywyn and the surrounding area has been obtained by
reviewing the ES carried out for the 2005 Scheme (ABPmer, 2005). No major fishing interests
were identified in the review.
4.14.2 Baseline Conditions
The North Western and North Wales Sea Fisheries Committee (NWNWSFC) is the Sea Fisheries
Committee for the Tywyn area. The fishing industry in Cardigan Bay focuses primarily on shell
fishing, with additional recreational fishing also taking place. There are presently around 35-40
commercially registered boats between Bardsey Island and Aberdyfi (CGC, 1998). There are no
major fishing ports situated close to Tywyn, although Aberdyfi is regarded as a small coastal
fishing port. The fishing methods utilised include potting, ‘musseling’, netting, rod and line and
recreational angling (Table 4.30). Cockling takes place, but not commercially (NWNWSFC, 2004)
and the closest designated shellfish waters are located in the Afon Dyfi, located 5km South of the
proposed works. Netting from boats represents a minor part of the industry whilst coastal fixed
netting is increasing (CGC, 1998).
Table 4.30 Fishing Effort Data for the Llyn Area
01/10/02 – 28/02/03 01/03/03 – 30/06/03
Fishing People Boats People Boats
Full Time 57 43 56 42
Part Time 105 81 105 81
Anglers 1017 687 1017 687
01/07/03 – 31/10/03 01/11/03 – 29/02/04
Fishing People Boats People Boats
Full Time 59 47 59 47
Part Time 108 70 108 70
Anglers 1122 627 647 367
Source: ABPmer, 2005
Commercial and recreational species caught in the coastal area extending from Barmouth to the
North of Tywyn to Cemaes Head to the South (referred to as the Llyn area) are shown in Table
4.31. There are no recorded fish species that spawn in the waters close to Tywyn although the
coastal area is used as a nursery ground by plaice and sole. The overall fishing effort for
demersal (living on or near the seabed) fish species is low and there is no fishing effort for pelagic
(open water) species. There is moderate fishing effort using static gear, low fishing effort for
beam trawlers, and no fishing effort for Nephrops / shrimp trawlers. There is no international
fishing effort in this area (Coull et al 1996).
Sea angling does occasionally take place along the Tywyn foreshore area since 15% of the
respondents approached for the review of recreational activities (see Section 4.9) said that they
undertake fishing/angling.
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Table 4.31 Fisheries Species Caught within the Llyn Area
Main Commercial
Species
Minor Commercial
Species Potting Bycatch Angling Species
Lobsters Mussels Spider Crab Spotted Dogfish
Prawns Herring Velvet Crab Bass
Bass Mullet Whiting
Scallops Codling Ray
Turbot Pollack Tope
Spotted Dogfish Whelks Black Bream
Ray Mackerel
Source: CGC, 1998
Shellfish
There are no designated shellfish waters in the vicinity of the foreshore and hence no commercial
shellfish harvesting in the vicinity of the proposed scheme at Tywyn. The closest shellfish waters
are located within the Dyfi estuary, at Aberdyfi approximately 7.5km South of the proposed site
(Food Standards Agency, 2003). The locations of the closest activities are listed below:
• Aberdyfi slipway: Ostrea edulis (native or flat oyster)
• Coed y Gofer: Cerastoderma edule (common edible cockle)
• Picnic Island: Mytilus edulis (blue mussel)
Salmon
Salmon fishing takes places on the Afon Dysynni to the North of Tywyn and the Afon Dyfi to the
South of Tywyn. Fishing on both rivers takes place using commercial net fishing (seine nets) and
rod and line fishing. Both rivers have failed to reach compliance for their current conservation
limits since 1995 (limit at which stocks should not be allowed to fall below) (CEFAS and
Environment Agency, 2002). A Salmon Action Plan for the Afon Dyfi has been prepared by the
EAW as part of its National Salmon Management Strategy (Environment Agency, 2003).
4.14.3 Assessment and Mitigation of Impacts during Construction
The impacts on fish biodiversity (noise, water and sediment quality) are detailed in Section 4.5.
Delivery Option A – delivery of large rock by sea
The delivery of materials by sea could disturb fishing activities that take place in the area (see
Section 2.3 for construction methodology details). There is a risk that the navigation routes of
local fishermen could be disturbed during the delivery of the rock to the Tywyn frontage.
However, little fishing takes place offshore of Tywyn in the vicinity of the works and the impacts to
fishermen in terms of access to fishing sites is considered to be neutral.
See Section 4.13 for impacts on navigation and Section 4.9 for impacts on water recreation.
A Notice to Mariners will, however, be issued to alert fishermen of works taking place. One
fisherman operates a boat from Tywyn itself and uses available slipways. During the construction
phase access to some of the slipways may be prohibited. However, the construction will be
phased in such a way that at least one slipway will remain useable at any time during the
construction. Overall any effects on fish or fishing activities are considered to be neutral.
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Delivery Option B – delivery of all materials by road
The impact on commercial and recreational fisheries is considered to be neutral (see Section 4.9
for impacts on water recreation).
4.14.4 Assessment and Mitigation of Impacts Post Construction
Due to the absence of fishing within the footprint of the scheme, the scheme and its new
structures will have no adverse impact (neutral) on existing fishing practices.
Full access to the foreshore will be resumed for anglers. However, some of the foreshore area
will be taken up by the new structures. However, the area lost to the new scheme is small and no
impacts (neutral) on angling post construction have been identified.
The repairs to the existing slipways and the improved shelter provided by the rock structures will
improve the launching of fishing vessels from these slipways. Although this could be seen as a
minor benefit, as only one fisherman is known to launch from the slipway, this benefit is not far-
reaching. The overall impact on fishermen using the slipways is therefore considered neutral.
4.15 In-Combination Impacts
There are no other coastal protection schemes known to be taking place along the Tywyn
Frontage or the adjacent coastline which could contribute to and increase the magnitude of the
impacts described above.
There are no other coastal schemes known to be taking place on the adjacent shores North or
South of the Tywyn frontage, managed by Network Rail and EAW respectively.
A coast protection and improvement scheme is planned on the Ceredigion coast at Borth, to the
South of the Dyfi estuary. The Dyfi estuary is a natural break / headland preventing the transport
of sediment from North of the Dyfi Southwards, or vice versa (see Section 4.4). In-combination
impacts are, therefore, considered to be neutral (see Section 4.9 for impacts on water
recreation).
The combined impacts of the 2009 Scheme are not considered to be significant if the mitigation
actions set out in this ES are followed. Delivery Option B would result in slightly greater combined
impacts, given the additional numbers of HGVs, increased site vehicle movements needed and
the increased noise generated by tipping rock when unloading vehicles. These impacts are,
however, time limited to the construction period (18 months duration). The combined impacts of
the 2009 Scheme post-construction are not considered to be significant.
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5. Conclusions and Recommendations This section contains a summary of all the environmental impacts on the baseline conditions of
the environmental receptors considered throughout this ES using the assessment criteria as
detailed in Section 4.1. Table 5.1 provides a summary of all of these effects for both the
construction and post-construction phases of the scheme.
‘Significant’ effects are considered to be those identified as ‘minor’, ‘moderate’ or ‘major’ and
either adverse or beneficial. Impacts that have been identified as ‘neutral’ and/or ‘negligible’ are
not considered to be significant.
5.1 Conclusions
Based on the summary presented in table 5.1 and the assessment undertaken in Section 4, the
2009 Scheme is considered to provide benefits to the residents and visitors to Tywyn by reducing
the impacts of coastal flooding and erosion and maintaining or improving the amenity value of and
access to the beach for the next 20 years.
Adverse environmental impacts are predominantly localised (within the area of the 2009 Scheme)
and time limited (during the 18 month construction period), providing the mitigation measures
proposed are followed. No adverse impacts to the coastal processes outside the site have been
identified.
5.2 Recommendations
Recommendations for managing construction to mitigate environmental impacts have been made
within the ES. The implementation of these measures will minimise any adverse environmental
impacts.
A copy of the Environmental Action Plan (EAP) that accompanied the tender documents for
prospective contractors is in Section 6. It should be noted that this only considered mitigation
measures for Delivery Option A. If the 2009 Scheme receives required planning permission and
FEPA / CPA consent, the EAP will need to be revised based on the successful contractor’s
delivery methodology and any conditions imposed by the decision making authorities.
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Table 5.1 Summary of Environmental Impacts
Environmental Receptor During Construction Post Construction
Coastal Processes
Sediment Budget / Transport Neutral – insignificant increase in sediment budget resulting from minimal release of sediment during construction
Minor beneficial – beach nourishment considered beneficial to the sediment budget in the first SMP2 epoch (0-20 years)
Neutral – impact of Warwick Place Breakwater on longshore sediment drift
Neutral – South Terminal Rock Groyne, Pier Road Rock Groyen and new timber groynes prevent movement of beach nourishment to adjacent frontages
Neutral – no impact upon the dune system – the 2009 Scheme does not interrupt the linkage between the foreshore and the dunes
Neutral – impact of Bryn-y-mor Rock Revetment on longshore sediment drift
Minor beneficial – beneficial stabilising effect of scheme on beach morphology, however no change in behaviour of the coastline is anticipated. Minimal increases in sediment budget as a result of beach nourishment
Coastal Processes / Shoreline Evolution
Neutral – negligible impact on overall coastal processes since complementary structures will be built at similar times
Neutral – minor adverse impact on coastal processes within the site in the first SMP2 epoch (0-20 years) reduced to neutral by the placement of Warwick Place Breakwater at an embryonic headland and the use of beach nourishment, which speeds the adjustment to a new system (by not drawing down material from other areas)
Neutral – no impact from the 2009 Scheme in comparison to natural processes within the site in the second SMP2 epoch (20 – 50 years)
Neutral – no impact outside of the site in the first SMP2 epoch in comparison to natural processes
Neutral – no impact on coastal processes outside of the site in the the second SMP2 epoch in comparison to natural processes
Neutral - no impact to the north of the site in the first SMP2 epoch
Neutral - no impact anticipated on the Dyfi geological SSSI to the south in the first SMP2 epoch
Neutral – no impacts on the SAC
Flora & Fauna
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Environmental Receptor During Construction Post Construction
Hinterland Flora and Fauna Neutral – no areas of biological interest to the landward side of the Scheme site
Neutral – no areas of biological interest to the landward side of the Scheme site
Neutral – no impacts on the dunes in adjacent areas
Intertidal Flora and Fauna Minor adverse – minor loss of non-SAC feature habitat / species by plant movement inside the SAC (10m x 50m area).
Neutral – no activity outside of Scheme site area impacts on adjacent areas
Delivery Option A – delivery of large rock by sea
Minor adverse – minor loss of habitat / species by plant movement and construction activities
Delivery Option B – delivery of all materials by road
Minor adverse – minor loss of habitat / species by plant movement and construction activities if site traffic routes are agreed with CCW/CGC prior to construction. The use of protective matting may also be required in some areas
Minor adverse – minor loss of habitat / species caused by footprint of new structures / loss of old groynes
Neutral – no impacts on flora and fauna in adjacent dune areas
Minor beneficial – provision of additional hard substrate for sessile species
Neutral – impact from beach nourishment – replaces lost substrate
Marine Flora and Fauna Minor adverse – small release of sediment resulting in minor smothering of any local vulnerable species
Neutral – impact on fish / shellfish from sediment release and noise
Neutral – impact on turbidity
Neutral – impact on marine mammals from noise
Neutral – no loss of SAC area
Neutral – no impacts from structures on fish species
Neutral – no impacts from beach nourishment on fish species
Birds Minor adverse – disturbance of birds in surrounding areas
Neutral – impact on bird beach feeding areas
Minor beneficial – provision of additional roosting / feeding source for birds
Neutral – no impacts on birds caused by footprint of new structures
Landscape & Visual Amenity
Landcover and Landform Moderate adverse – presence of site compounds will result in temporary change in landscape resources during construction
Slight adverse – effects of presence of rock revetment and breakwater upon landscape resources
Landscape Character Substantial adverse – construction activities within the normally peaceful landscape will result in a detrimental change to landscape character throughout the construction period
Slight beneficial – remedying of poor coastal defences and improvement in functionality, including reduction in future flood events offset introduction of incongruous elements into the area
Existing Site Use Substantial adverse – restricted access to beach and promenade will have detrimental impact on the tourist trade
Moderate beneficial – improved amenity of beach areas, including better access to the beach and new stepped apron
ENVIRONMENTAL STATEMENT
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Environmental Receptor During Construction Post Construction
Visual Amenity Impacts Slight adverse – construction traffic and activity will have slight impact upon properties on Marine Parade
Moderate adverse – proximity of the satellite site compound will impact properties on Marine Parade
Moderate adverse – users of public toilets on Marine Parade impacted as a result of construction traffic and activity
Slight adverse – users of the playground on Marine Parade will be impacted due to distance from the satellite site compound and site traffic. In addition to this the view from the playground will also be interrupted
Moderate adverse – proximity of works and satellite site compound to Gwynedd Caravan Park
Slight adverse – during off peak season construction works will have a slight disturbance upon Gwynedd Caravan Park
Substantial adverse – proximity of the site compound to Bryn-y-mor Caravan Park
Slight adverse – during off peak season construction works will have lesser impact upon Bryn-y-mor Caravan Park
Substantial adverse – proximity of site to areas of beach still in use
Neutral – views from ground floor properties at Northern end of Marine Parade screened by intervening planting on the East side of adjacent car park
Slight adverse – ground floor properties in centre of Marine Parade will have views of the Warwick Place Breakwater, however this will be offset by the improved view resulting from the new shortened groynes
Moderate adverse – ground floor properties at South of Marine Parade will have views of the Warwick Place Breakwater
Neutral – upper floor properties along Marine Parade look out upon the Warwick Place Breakwater, however this will be offset by the benefit from the shortened groynes
Moderate adverse – views of Warwick Place Breakwater impacts on users of public toilets on Marine Parade from
Slight Beneficial – improved view from the play ground on Marine Parade resulting from shortened groynes
Slight adverse – notable adverse impacts to Gwynedd Caravan Park resulting from Warwick Place Breakwater will be counterbalanced by replaced/removed timber groynes
Slight beneficial – positive impact upon Bryn-y-mor Caravan Park from renovation of groyne field
Slight beneficial – users of beach will experience a benefits from the new stepped apron, beach nourishment and refurbishment of groyne field, these will be offset by the Warwick Place Breakwater
Water and Sediment Quality
Water and Sediment Quality Minor adverse – any release of sediments will be limited to very small quantities
Neutral – no evidence that in-situ sediment contains any contaminants
Neutral – imported sediment will contain no contaminants
Minor adverse – potential impact from spills and leakages from construction plant
Neutral – very small increase in turbidity due to natural washing of recharge material – time limited
Traffic and Transport
Volume of Traffic Delivery Option A – delivery of large rock by sea
Moderate adverse – predicted increase in volume of traffic of up
Minor beneficial – increase in functionality of defence structures will provide increased protection to Marine Parade from flooding. This is offset by the occasional access required by vehicles/plant to maintain
ENVIRONMENTAL STATEMENT
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Environmental Receptor During Construction Post Construction
to 30% for the period of February 2010 – time limited
Delivery Option B – delivery of all materials by road
Moderate adverse – predicted increase in volume of traffic for most of the 18 month construction period – time limited – consideration to be given to pre/post construction road surveys in vulnerable areas and to alerting residents in areas where congestion may arise(in consultation with CGC Highways)
defence structures
Recreation and Amenity
Beach Recreation Moderate adverse – during construction some areas of the beach will be off limits to the public
Negligible – passage along the beach at MLW will remain unchanged
Minor adverse – when steps to the beach are under repair, access to the beach will be available using adjacent steps
Delivery Option A – delivery of large rock by sea
Minor adverse – overall impact of works on beach recreation – time limited
Delivery Option B – delivery of all materials by road
Moderate adverse – overall impact of works on beach recreation – time limited
Minor adverse – loss of beach area due to footprint of rock structures
Minor adverse – impact of Warwick Breakwater on beach access
Minor beneficial – shorter rock groynes will improve passage along beach
Neutral – impact resulting from presence of the Bryn-y-mor revetment
Moderate adverse – people climbing on/over the rock structures
Minor beneficial – beach nourishment behind the Warwick Place Breakwater
Moderate beneficial –new timber groynes will improve along shore passage
Moderate beneficial – enhanced seating area as a result of repairs to concrete steps and seawall
Water Recreation Delivery Option A – delivery of large rock by sea
Minor adverse – impact on water users from approaching and moored vessels
Minor adverse – impact resulting from repairs to slipways
Delivery Option B – delivery of all materials by road
Neutral – impact on water users from approaching and moored vessels
Moderate adverse – impact resulting from unavailability of slipways – time limited
Neutral – no change to offshore wave patterns
Neutral – risk of scheme to swimmers
Minor Adverse – risk of collision with structures from recreational and commercial boats
Minor Beneficial – impact to three slipways
Promenade Recreation Minor adverse – impact on promenade users from presence of plant and machinery
Moderate beneficial – overall impact upon the promenade as a result of scheme (e.g. viewing platform, improved protection)
Parking facilities Minor adverse – impact on parking space availability Minor beneficial – provision of greater protection to frontage from wave overtopping
ENVIRONMENTAL STATEMENT
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Environmental Receptor During Construction Post Construction
Noise
Construction Noise Delivery Option A – delivery of large rock by sea
Moderate adverse – overall impacts of construction noise on local residents and visitors
Delivery Option B – delivery of all materials by road
Major adverse – overall impacts of greater level of delivery and construction noise on local residents and visitors
Neutral – no impacts on existing noise levels
Air Quality
Air Quality Delivery Option A – delivery of large rock by sea
Neutral – overall impacts upon air quality during construction
Delivery Option B – delivery of all materials by road
Minor adverse – overall impacts upon air quality during construction
Neutral – no impacts from structures on air quality
Historic Environment
Archaeological features of interest Minor adverse – impacts of construction work upon and adjacent to the promenade
Minor adverse – potential impacts upon possible peat deposits (turbary and peat beds) within the study area
Minor adverse – impacts upon possible peat deposits (turbary and peat beds) adjacent to the study area
Moderate beneficial – impact of scheme upon promenade through the provision of increased protection from waves
Neutral – no impacts resulting from the scheme upon peat deposits (turbary and peat beds) within study area
Neutral – no impacts resulting from scheme upon peat deposits (turbary and peat beds) adjacent to the study area
Navigation
Navigation Delivery Option A – delivery of large rock by sea
Minor adverse – impacts upon navigation immediately offshore of Tywyn
Neutral – no impacts expected upon navigation to the South of Tywyn (Aberdyfi Harbour)
Delivery Option B – delivery of all materials by road
Neutral – impacts upon navigation immediately offshore of Tywyn
Neutral – no impacts expected upon navigation to the South of
Neutral – impacts of the scheme upon navigation
Minor beneficial – increased shelter provided to the slipways by Warwick Place Breakwater will be beneficial to navigation from the beach
Neutral – no impact upon RNLI navigation routes
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Environmental Receptor During Construction Post Construction
Tywyn (Aberdyfi Harbour)
Commercial and Recreational Fisheries
Fishing Neutral – access to fishing sites will not be interrupted
Neutral – there will be no impacts upon fish biodiversity
Neutral – access to a slipway to enable launching of vessels will be possible throughout construction
Neutral – overall impacts upon fishing activities
Neutral – new structures will have no impact upon existing fishing practices
Neutral – some loss of foreshore available for anglers
Neutral – repairs/replacement of the slipways will benefit the launching of fishing vessels from Tywyn, however there is only 1 fisherman launching from Tywyn currently
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6. Environmental Action Plan 6.1 Introduction
This Draft Environmental Action Plan (EAP) was produced to accompany the tender documents
for prospective contractors as part of the procurement process by CGC. At the time of production,
the possibility of delivering all materials by road was not considered.
The EAP will, therefore, need to be updated to take account of the preferred contractor’s delivery
methodology (by sea, by road or a mix of both methods) and the associated impacts and
proposed mitigation methods set out in this ES, along with any specific planning or licensing
conditions that may be applied if consents are granted for the 2009 Scheme. Updating of the EAP
will be undertaken in consultation with CGC, EAW and CCW when a contractor has been
appointed and will be reviewed throughout the construction period.
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Table 6.1 Draft Environmental Action Plan
ENVIRONMENTAL ACTION PLAN
Ref.
No. Objective Action Target Responsibility
Reference
to further
information
Monitoring
and
Observation
Further Action
Required
(Y/N)
PRIOR TO CONSTRUCTION
Pr1 RECREATION AND AMENITY
Pr1.1 Ensure local residents and tourists visiting the Tywyn frontage are aware of when and why the works are being undertaken
Signs and notices to be erected along the frontage prior to construction. Contact details will be provided on all information sources in the event of complaints and requests for further information
No valid complaints regarding lack of information prior to construction
CGC
Pr2 FLORA AND FAUNA
Pr2.1 Reduce risk of damage to adjacent designated conservation sites
Environmental Site Supervisor to be appointed and to make Contractors aware of designated conservation sites and environmental constraints
Contractors fully informed of location of designated sites and the environmental constraints
CGC/
Contractor
Pr3 WATER AND SEDIMENT QUALITY
Pr3.1 Ensure imported recharge material does not contain contaminants harmful to human health and the marine environment
Contamination testing to be carried out of sourced material prior to construction. Should harmful contaminants be found, an alternative source of beach material is to be identified
Beach material to be sourced from an uncontaminated source. Evidence of contamination testing to be produced
Contractor
Pr3.2 Ensure no water pollution from leaks and spills from construction plant and machinery
All staff on site to be briefed on the emergency procedures before commencing works
Staff fully briefed on emergency procedures
Contractor
Pr4 CULTURAL HERITAGE & ARCHAEOLOGY
ENVIRONMENTAL STATEMENT
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138
ENVIRONMENTAL ACTION PLAN
Ref.
No. Objective Action Target Responsibility
Reference
to further
information
Monitoring
and
Observation
Further Action
Required
(Y/N)
Pr4.1 Reduce disturbance and damage to peat deposits
Trial-pits for evidence of peat deposits to be carried out prior to construction. The results may require the development of a mitigation programme, which may include an archaeological watching brief
Surveys carried out prior to construction and Contractor to be informed of any mitigation measures requiring implementation
CGC
Pr4.2 Reduce the risk of damage to the Promenade
Condition survey to be carried out prior to construction
Weak/vulnerable points identified and mitigation measures where necessary identified and implemented. No damage to promenade as a result of construction
Contractor
Pr5 LANDSCAPE & VISUAL AMENITY
Pr5.1 Ensure local residents and tourists visiting the Tywyn frontage are aware of when and why the works are being undertaken
Signs and notices to be erected along the frontage prior to construction. Contact details will be provided on all information sources in the event of complaints and requests for further information
No valid complaints regarding lack of information prior to construction
CGC
Pr6 NOISE
Pr6.1 Ensure local residents and tourists visiting the Tywyn frontage are aware of when and why the works are being undertaken
Signs and notices to be erected along the frontage prior to construction. Contact details will be provided on all information sources in the event of complaints and requests for further information
No valid complaints regarding lack of information prior to construction.
CGC
Pr7 TRAFFIC AND TRANSPORT
ENVIRONMENTAL STATEMENT
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ENVIRONMENTAL ACTION PLAN
Ref.
No. Objective Action Target Responsibility
Reference
to further
information
Monitoring
and
Observation
Further Action
Required
(Y/N)
Pr7.1 Minimise the risk of accidents from any construction traffic through the town
Access routes to be defined in contract documents
Access routes clearly specified in contract documents
CGC
Pr8 NAVIGATION
Pr8.1 Ensure safe navigation Notice to Mariners to be issued prior to commencement of works
Signs to be erected by slipways informing of works
No valid complaints of lack of information prior to construction No valid complaints of lack of information prior to construction
Contractor
CGC
Pr9 FISHERIES
Pr9.1 Ensure navigation routes used by local fishermen are maintained
Notice to Mariners to be issued prior to commencement of works
Fisheries Liaison Officer to be appointed to agree navigation routes and working methods with local fishermen prior to construction
No valid complaints of lack of information prior to construction
Contractor
Pr9.2 Reduce disruption to angling activities
Signs to be erected along frontage, including the car parks prior to construction informing of work
No valid complaints of lack of information prior to construction
CGC
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ENVIRONMENTAL ACTION PLAN
Ref. No.
Objective Action Target Responsibility Reference to further information
Monitoring and Observation
Further Action Required
(Y/N)
DURING CONSTRUCTION
D1 RECREATION AND AMENITY
D1.1 Ensure minimal construction disturbance to local residents, tourists and beach users
Signs and notices to be erected along the frontage, site compound and working area during construction providing information of the works. Contact details will be provided on all information sources in the event of complaints and requests for further information Contractor to employ beach marshals to be on site to provide information to the public
Contractor to produce a Construction Environmental Management Plan (CEMP) which will detail the management of the site and working procedures in accordance with best practice guidelines
Any valid complaints regarding construction disturbance to be satisfactorily resolved
No valid complaints regarding persons unable to obtain information of the works.
CEMP produced and management measures implemented
CGC/
Contractor
Contractor
Contractor
D1.2 Minimise the risk of accidents to recreational and amenity users from presence and movement of plant and machinery on the beach and in the water
Signs and notices to be erected along the frontage, site compound and working area during construction providing information of the works
Good working practices to be adhered to such as ensuring the site is kept secure (e.g. with fencing) and in good order
No valid complaints regarding lack of information prior to construction
Site is secure at all times
Contractor
Contractor
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ENVIRONMENTAL ACTION PLAN
Ref. No.
Objective Action Target Responsibility Reference to further information
Monitoring and Observation
Further Action Required
(Y/N)
Contractor to employ beach marshals to be on site to provide information to the public and to keep people away from potentially dangerous areas
CEMP to include working practices to reduce risk of accidents on site
Contractor to obtain contact details of RNLI and Coastguard and Contractor’s contact details to be provided to RNLI and Coastguard
Beach marshals present on site and people kept away from potentially dangerous areas
CEMP produced and management measures implemented
Contact details circulated
Contractor
Contractor
Contractor
D1.3 Reduce disruption to recreational beach activities
Signs and notices to be erected along the frontage, site compound and working area during construction providing information of the works
Contractor to employ beach marshals to be on site to provide information to the public and to keep people away from potentially dangerous areas
No valid complaints regarding lack of information
Beach marshals present on site and people kept away from potentially dangerous areas
Contractor
Contractor
D2 FLORA AND FAUNA
D2.1 Minimise damage to adjacent designated conservation sites
Environmental Site Supervisor to liaise with Contractor to ensure that mitigation measures are adhered to (including actions from Environmental Statement and Habitats Regulations Assessment)
No damage to features of designated sites All measures implemented
Contractor
D3 WATER AND SEDIMENT QUALITY
ENVIRONMENTAL STATEMENT
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142
ENVIRONMENTAL ACTION PLAN
Ref. No.
Objective Action Target Responsibility Reference to further information
Monitoring and Observation
Further Action Required
(Y/N)
D3.1 Ensure no significant increase in turbidity levels as a result of construction
Environmental Site Supervisor to liaise with Contractor to ensure that mitigation measures are adhered to (including actions from Environmental Statement and Habitats Regulations Assessment)
All measures implemented
No significant decrease in water quality resulting from construction
Contractor
D3.2 Ensure no pollution of the water
Refuelling of vehicles or machinery must take place away from the beach and within a designated refuelling area. Vessels will return to a nearby port for refuelling
Vehicles, vessels and machinery will be well-maintained to ensure no leakages of fuel or engine oil
Oils or chemicals used on land or at sea will be stored in suitable bunded containers
Machinery and equipment in the site compound will be locked away at night and when works are not being undertaken to minimise the risk of vandalism
The Contractor will adhere to the Environment Agency Pollution Prevention Guidance 21 and the Government’s Planning Policy Statement 23
Contractor to have an emergency response procedure in place in the event of a chemical leak or spill both on land and at sea
No pollution incidents
No significant decrease in water quality resulting from construction
Contractor
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ENVIRONMENTAL ACTION PLAN
Ref. No.
Objective Action Target Responsibility Reference to further information
Monitoring and Observation
Further Action Required
(Y/N)
The Contractor will include details on the management of pollution risk both on land and at sea in the CEMP
D3.3 Reduce the risk of cement entering the water during slipway construction
Contractor to follow best practice guidelines relating to reducing concrete losses during marine construction
No significant concrete pollution of marine waters
Contractor
D4 CULTURAL HERITAGE AND ARCHAEOLOGY
D4.1 Ensure no disturbance and damage to peat deposits
Any mitigation measures identified from the pre-construction surveys to be implemented (see Pr4.1)
Construction vehicles and machinery to remain within foot print of the scheme
No disturbance or damage to peat deposits as a result of construction
Contractor
D4.2 Ensure no damage occurs to promenade
Use of banksmen during construction adjacent to promenade
No damage to promenade as a result of construction
Contractor
D5 LANDSCAPE AND VISUAL IMPACTS
D5.1 Ensure minimal disruption to landscape character and views
CEMP to be produced which will detail the management of the site (keeping it tidy and contained by fencing), including waste management
Signs to be erected informing the public of the works and providing contact details in the event of complaints or requests for further information
Mitigation measures outlined in Landscape & Visual Impact
No valid complaints of disruption to landscape character and views
Contractor
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ENVIRONMENTAL ACTION PLAN
Ref. No.
Objective Action Target Responsibility Reference to further information
Monitoring and Observation
Further Action Required
(Y/N)
Assessment to be adhered to
D6 NOISE
D6.1 Ensure disturbance from noise is minimised
Contractor to adhere to relevant British Standards, including BS5228:1997, Part 1, Annex B ‘Noise Control and Open Sites’
All machinery to be well-maintained and fitted with appropriate muffling or silencing equipment
During night-time working hours (between 7pm and 7am), reversing sirens to be replaced with hissers (only applicable to the plant used to unload rock from barges)
Shift workers accessing the site during night-time hours to use cars or light goods vehicles
Land-based construction traffic travelling to and from the site to be limited to travelling between the hours of 7am and 7pm
Signs and notices to be erected along the frontage, site compound and working area during construction providing information of the works. Contact details will be provided on all information sources in the event of complaints and requests for further information
No valid complaints of noise disturbance
Contractor
ENVIRONMENTAL STATEMENT
Tywyn Coastal Improvement Scheme
145
ENVIRONMENTAL ACTION PLAN
Ref. No.
Objective Action Target Responsibility Reference to further information
Monitoring and Observation
Further Action Required
(Y/N)
Contractor to employ beach marshals to be on site to provide information to the public
CEMP to include noise reduction measures in accordance with best practice guidelines
D7 TRAFFIC AND TRANSPORT
D7.1 Minimise disruption to traffic and transport
Access routes as defined in contract documents to be adhered to
Delivery vehicles to travel between 8am and 7pm and to adhere to best practice guidelines regarding speed
CEMP to detail the management of construction traffic in accordance with best practice guidelines
Workers arriving and leaving the site outside of these hours to use either cars or light goods vehicles
Access routes clearly specified in contract documents
No valid complaints of deliveries of materials outside of specified hours or at excessive speeds
CEMP produced and management measures implemented
No valid complaints regarding traffic and disruption disturbance
Client
Contractor
Contractor
Contractor
D7.2 Minimise disruption to fishermen navigation
Fisheries Liaison Officer to liaise and agree with fishermen regarding access routes to and from the site
No disruption to fishing activities
Contractor
D8 AIR QUALITY
D8.1 All roads used by construction traffic to be kept free from mud and dust
Washing wheels of vehicles when leaving the site
Ensuring vehicles are kept clean
Damping down roads and
No valid complaints of poor road quality resulting from construction traffic
Contractor
ENVIRONMENTAL STATEMENT
Tywyn Coastal Improvement Scheme
146
ENVIRONMENTAL ACTION PLAN
Ref. No.
Objective Action Target Responsibility Reference to further information
Monitoring and Observation
Further Action Required
(Y/N)
construction areas if conditions become dry and dusty
D9 NAVIGATION
D9.1 Minimise disruption to recreational vessels
Signs to be erected by slipways informing of works
Beach marshals present on site to provide information to boat users using the slipways
No valid complaints Contractor
D9.2 Ensure navigation routes of local fishermen are maintained
Fisheries Liaison Officer to liaise with fishermen throughout construction
No disruption to existing fishing practices
Contractor
D10 FISHERIES
D10.1 Ensure navigation routes of local fishermen are maintained
Fisheries Liaison Officer to liaise with fishermen throughout construction
No disruption to existing fishing practices
Contractor
D10.2 Reduce disruption to angling activities
Signs and notices to be erected along the frontage, site compound and working area during construction providing information of the works
Contractor to employ beach marshals to be on site to provide information to the public and to keep people away from potentially dangerous areas
No valid complaints regarding lack of information
Contractor
D10.3 Ensure no damage to fishing nets
Any large objects dropped into the water during construction are to be recovered
No damage to fishing nets as a result of construction
Contractor
ENVIRONMENTAL STATEMENT
Tywyn Coastal Improvement Scheme
147
ENVIRONMENTAL ACTION PLAN
Ref. No.
Objective Action Target Responsibility Reference to further information
Monitoring and Observation
Further Action Required
(Y/N)
POST CONSTRUCTION
Po1 RECREATION AND AMENITY
Po1.1 Ensure minimal disruption to local residents and tourists from future maintenance work
Same as Pr1.1 and D1.1
No valid complaints of lack of information and any valid complaints regarding construction disturbance to be satisfactorily resolved
CGC/
Contractor
Po1.2 Ensure public safety with regards the presence of new rock structures and the risk of people becoming injured from climbing on them
Signs to be erected advising the public not to climb on rocks
Signs erected and public informed of risks
CGC
Po1.3 Ensure the safety of swimmers with regards the risks of swimming close to the new rock structures
Signs to be erected advising of dangers
Signs erected and public informed of risks
CGC
Po2 FLORA AND FAUNA
Po2.1 Minimise damage to adjacent designated conservation sites during maintenance work
Same as Pr2.1 and D2.1 No significant adverse impacts on conservation sites
Contractor
Po3 WATER AND SEDIMENT QUALITY
Po3.1 Ensure no significant increases in turbidity levels during maintenance operations
Same as D3.1
All measures implemented
No significant decrease in water quality resulting from maintenance works
CGC/
Contractor
Po3.2 Ensure no pollution of the water during maintenance
Same as Pr3 and D3.2 No pollution incidents as a result of maintenance
CGC/
ENVIRONMENTAL STATEMENT
Tywyn Coastal Improvement Scheme
148
operations
operations
No significant decrease in water quality resulting from maintenance works
Contractor
Po4 CULTURAL HERITAGE AND ARCHAEOLOGY
Po4.1 Ensure no disturbance and damage to buried peat deposits during maintenance works
Same as D4
No damage to peat deposits
CGC/
Contractor
Po5 LANDSCAPE AND VISUAL AMENITY
Po5.1 Ensure minimal disruption to landscape character and views during maintenance works
Same as Pr5 and D5
No valid complaints of disruption to landscape character and views
CGC/
Contractor
Po6 NOISE
Po6.1 Ensure disturbance from noise is minimised during maintenance works
Same as Pr6 and D6
No valid complaints of noise disturbance
CGC/
Contractor
Po7 TRAFFIC AND TRANSPORT
Po7.1 Minimise disruption to traffic and transport during maintenance works
Same as Pr7 and D7
No valid complaints regarding disruption to traffic and transport
CGC/
Contractor
Po8 NAVIGATION
Po8.1 Ensure safety with regards navigation during maintenance works
Navigational aids to be provided on new structures in consultation with Trinity House Signs to be provided at the slipways along the frontage informing of safe navigational requirements
Navigation aids installed
Signs erected and boat users informed of risks
Contractor
CGC
Po8.2 Maintain navigation routes for local fishermen during maintenance work
Same as Pr8.1 No valid complaints of lack of information
No disruption to fishing activities
CGC/
Contractor
Po9 FISHERIES
ENVIRONMENTAL STATEMENT
Tywyn Coastal Improvement Scheme
149
Po9.1 Ensure minimal disruption to anglers from future maintenance work
Same as Pr9.2 and D10.2
No valid complaints of lack of information
No disruption to angling activities
CGC/
Contractor
Po9.2 Maintain navigation routes for local fishermen during maintenance work
Bray, M; Carter, D. & Hooke, J. 2004. South Coast Sediment Transport Study. Report to SCOPAC. Five Volumes, 1200p. and CD-ROM. especially Volume 3 Hurst Castle Spit to Chichester Harbour Entrance.website version: www.scopac.org.uk/scopac%20sediment%20db/preface.htm
Cardigan Bay Coastal Group, 2002. Cardigan Bay Shoreline Management Plan Overview, http://www.ceredigion.gov.uk/external/shoreline/english/adobe/North%20Cardigan%20Bay%20SMP%202003%20-%20English/North%20Cardigan%20Bay%20SMP%20%202003%20Stage%203.pdf
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Marine Pollution Monitoring Management Group, 1998. National Monitoring Programme: Survey of the Quality of UK Coastal Waters.
MNCR 1995. MNCR data moved to http://www.searchnbn.net/ and http://www.searchmesh.net/mermaid
MNCR 1997. MNCR data now moved to http://www.searchnbn.net/ and http://www.searchmesh.net/mermaid
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National Statistics Online, 2009. Statistics about Tywyn. 2007 census [online]. Available from: - http://neighbourhood.statistics.gov.uk/dissemination
Pethick, J., 1996. Shoreline Intervention Proposals: Afon Dysynni to Aberdyfi. The Dyfi Estuary and the Aberdyfi Coast. Report to the Countryside Council for Wales.
K Pye and Associates Ltd, 2005. The Geomorphological response of Welsh Sand Dunes to Sea Level Rise over the next 100 years and the management implications for SAC and SSSI sites. CCW Contract Science Report Number 670.
Shoreline Management Partnership, 1995. Afon Dysynni to Aberdyfi Shoreline Management. Project Appraisal Report. For Meirionnydd District Council.
Shoreline Management Partnership, 1994. Shoreline Management – Afon Dysynni to Aberdyfi. Intervention Appraisal Report. For Cardigan Bay Coastal Group.
ENVIRONMENTAL STATEMENT
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152
Shoreline Management Partnership, 1993 Meirionnydd Coastal Management Study
Tougaard, J, Carstensen, J, Henricksen, JD, Skov, H, Teilmann, J, 2003. Short Term Effects of the Construction of Wind Turbines on Harbour Porpoises at Horns Reef. Technical Report Techwise A/S.
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UKHO, 1972. Tidal Diamond Admiralty Chart
UK Met Office, 2009. UK Waters Wave Model for the year 2003.
WAG, 2007a, New Approach to Flood Defence in Wales, Press Release 23 July 2007, http://wales.gov.uk/news/topic/environment/2007/1589616/?lang=en
WAG, 2007b, Flood Risk Management in Wales, Written Cabinet Statement 17 September 2007, http://wales.gov.uk/about/cabinet/cabinetstatements/2007/1680136/?lang=en