Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.
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Every drop countsEnvironmentally Sound Technologies (ESTs)for urban and domestic water use efficiency
Presentation of key issues and tools
every drop counts
Every drop counts presentation
Delft University of Technology production of the presentation: Dr. Aad F. Correlje, Faculty of Technology, Policy & Management Dr. Ing. Thorsten Schuetze, Faculty of Architecture Dr. Sybrand P. Tjallingii, Faculty of Architecture Dr. Maki Ryu, Faculty of Architecture
UNEP DTIE IETCcoordination: Vicente Santiago
every drop counts
Structure of the presentation
1. Introduction
2. Backgrounds of decision making Policies, Criteria
3. Environmentally Sound Technologies Storage, Supply, Use, Reuse & Recycling
4. Integrated options and cases
5. Questions for a specific case
Objective and target group
• To support decision making about Environmentally Sound Technologies (ESTs) in urban and domestic water use.
• A sourcebook that highlights essential questions that have different answers in different cases towards water use efficiency
• Decision makers: participants in local planning processes related to urban and domestic water use
objective
target group
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1. Introduction
Scope and focus
• Water use efficiency in urban and domestic environments
• Other water issues (e.g. flooding, drainage, irrigation) only if relevant
• Urban includes all concentrated settlements
• Efficient use of ESTs• Efficient is: optimizing the balance
between demand and safe and sufficient supply
• Efficient and fit : technologies that fit in with sustainable perspectives for the local situation
scope
focus
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1. Introduction
Sourcebook, presentation and WiseWater training module• Backgrounds: policies, criteria
• Relevant issues for analysis and discussion
• A toolkit of environmentally sound technologies
• Illustrative cases
• Summary of the sourcebook• Questions for decision making in your own
case
• Calculating the effects of water saving technologies (ESTs) versus conventional technologies
sourcebook
presentation
WiseWater
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1. Introduction
every drop counts
2. Backgrounds Policies
Policies and institutions
technology
institutions
economy
[Sourcebook Chapter 2]
The challenge is to achieve an appropriate 'fit' between the 'hard' technical and physical characteristics, the economics of ESTs and the institutional environment that facilitates their selection, construction and operation.
Decision-making in a complex institutional actor network• National, or regional governmental
bodies. • Local actors: agencies for water
management, municipalities, water supply corporations, sewerage operators, public health policy makers, housing corporations, project developers, financing parties.
• Construction companies and equipment suppliers.
• The users of the water systems, domestic households in owned and rented houses, small and medium size enterprises, and the citizens living in the areas.
The actors:
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2. Backgrounds Policies
Policy, Rules and UseWhat does it imply ? • Policies ?• Project
development ?• Implementation ?• Operation ?
Introducing ESTs:
Embeddedness Informal institutions, customs, traditions,
norms, religion
Institutional environment Formal
rules of the game, property, water laws, bureaucracy
Governance Play of the game,
contracting, aligning governance structures with
transactions
Resource allocation and
development Prices and quantities,
incentive management
All these activities have to be considered in the context of the four layers of the institutional framework.every drop
counts2. Backgrounds Policies
National Water Policy• The water cycle, requiring integrated water
re- sources management: surface water, ground- water, catchment-basin and land-use planning.
• The environment as the source of water: water collection control, augmentation, water quality and pollution control.
• Principles for water use by the domestic households, agriculture, industry, tourism, etc.
• Economic principles of water management: water pricing, financing, the role of the private sector.
• Roles, responsibilities and authority of water institutions: like federal and state institutions, user engagement, basin organizations, etc.
Policy addresses many activities:
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2. Backgrounds Policies
Local decision making• Patterns of
water supply and sanitation
• Patterns of (sectoral) water use
• Environmental aspects, ecosystem approach
• Institutional arrangements, legal framework
• Social and cultural factors• Positions of stakeholders and interest
groups• Economics and the engagement of the
private sector• Interaction with other infrastructures and
assets
Diagnosis as a basis for planning:
diagnosis
planning
operation implementation
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2. Backgrounds Policies
Problems in planning and implementation
• Technically inadequate plans, lack of ESTs.
• Socially and culturally unacceptable plans.
• Economically unfeasible plans.• Plans which make too great a demand on
available human resources.• Plans that go counter to legal provisions.• Plans that are blocked by other local
departments because of lack of coordination and consultation.
• External factors such as poor public servant morale or public resistance.
Plans that fail:
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2. Backgrounds Policies
Operation, economic and financial aspects
• Most beneficial use and exploitation, balancing social and environmental requirements.
• Water has a value and water supply and sanitation have a cost.
• Pricing and tariff arrangements. • Budgetary resources, subsidies and tariff
revenue.• The role of the private sector.• Support towards the introduction of ESTs.
Issues:
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2. Backgrounds Policies
Risk, revenues and governance
Innovation and change cannot go without risks.
• Identify the main areas of responsibility and the risks associated. Shared understanding of risks is the basis.
• Assign the responsibilities and risks to the party best able to manage them.
• Bearing risk has a cost and the party bearing the risk will likely demand something in return.
• A public regulator should secure the
benefits for society and the environment.
Recommen-dations:
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2. Backgrounds Policies
Environmentally sound water policies
• Sustainable water management, a vital aspect of economic development in poor regions.
• The economic value of water establishes mechanisms that can enhance water efficiency. Policies should create conditions for the poor to have access to water.
• Public participation: practical experience of what works and what does not. Planning is learning.
Summary of key issues:
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2. Backgrounds Policies
Environmentally sound water policies (cont.)
• Gender issues are crucial in water management, especially at the domestic level.
• Expertise is crucial. Foreign advisers may play a role but only local expertise can ensure that policies meet local needs and local conditions.
• Ecosystem approach as a fundamental component of Integrated Water Resource Management (IWRM).
Summary of key issues:
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2. Backgrounds Policies
Criteria for decisionsAt the local decision level there is a need for practical criteria that can guide ‘the actors’, those who participate in the planning process.
Efficient is the best known criterion. An efficient technology (EST) produces high results (sufficient water for households, farming, industry, health) with low efforts (money, time, resources, human energy). Technologies can also be more or less efficient in saving water. Calculating efficiency is very helpful for making decisions.
But it is not the only criterion. The Bissau case serves as an illustration:
[Sourcebook Chapter 3]
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2. Backgrounds Criteria
The Bissau case
Like many cities in developing countries, Bissau City (W.Africa) faces water and sanitation problems in squatter areas. A neighbourhood upgrading programme realises new tap stands, new latrines and new drainage gutters.
new watertaps new pour-flush latrinespoor sanitation
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2. Backgrounds Criteria
Learning from a case1. New taps not reliable (power failures). Thus people turn to old wells that pose higher health risks (latrines too close, clean rainwater efficiently drained away). Plans for flows must fit together. 2. Improved drainage in neighborhoods leads to
erosion in the urban fringe. Plans for areas must fit together. 3. Construction work performed well but manage- ment and maintenance fail. Plans for actors must fit together.
in addition to efficiency, there is a group of criteria called fit. They have to be specified for flows and areas and actors.
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2. Backgrounds Criteria
Specific criteria for the local plan
General criteria for sustainable plans
FLOWS which flows?
choices made?
AREAS which areas?
choices made?
ACTORS which actors,
choices made?
PLANET PEOPLE PROSPERITY (ecological) (social) (economic) sustainable is:- sound use
and liveability
- participation - fair sharing - gender
- profit and development
guiding principles
guiding models
How to make a sustainable water plan?
Specifying ‘fit’ criteria for local plans
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2. Backgrounds Criteria
Working with ‘fit’ criteria
• First, an analysis should provide the relevant information: > Which flows ? (e.g. rainwater, groundwater, drinking water, waste water, solid waste, energy) > Which areas ? (e.g. houses. yards, streets, neighbourhoods, urban fringe) > Which actors? (e.g. women, families, shopkeepers, agencies, NGOs).
• Secondly, alternative plans (combinations of technologies, policies and spatial plans) can be discussed using general criteria for sustainable plans and specific arguments from the local context.
Analysis
Discussion
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2. Backgrounds Criteria
The planning cycle
Fit and efficiency in the planning cycle
initiative
use maintenance
realization
detailed design
strategic plan
starting document
ORIENTATION
GUIDING PRINCIPLES
ANALYSIS > flows > areas > actors
EXAMPLES
GUIDING MODELS
EVALUATION
efficiency
fit
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2. Backgrounds Criteria
Criteria in the planning cycle• The strategic stage of the planning cycle (from initiative to strategic plan) focuses on sharing the understanding of the problem, sharing the general approach and sharing the responsibility for solutions. ‘Fit’ criteria usually dominate the process.
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2. Backgrounds Criteria
Criteria in the planning cycle• The operational stage of the planning cycle (from strategic plan to realization and use) focuses on specifying concrete solutions, specifying the funding, the contracts and the organization of construction and maintenance. ‘Efficiency’ criteria usually dominate the process.
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2. Backgrounds Criteria
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3. ESTs Intro
Environmentally Sound Technologies in the Urban Water Cycle
storage & augmentatio
n
reuse,recycle & disposal
use & saving
supply & distribution
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3. ESTs Storage
Storage and augmentation ESTs
1. Ponds and Reservoirs
2. Artificial recharge of Groundwater
3. Water Tanks
4. Rainwater runoff in surface water
5. Rainwater runoff in groundwater
6. Rainwater runoff in tanks
7. Effluent in surface water
8. Effluent in ground water
[Sourcebook Chapter 4.2]
Ponds and reservoirsDams and reservoirs are a common approach to storage of river water. Big dams, however, do often cause big unsolved problems and therefore cannot be called environmentally sound. Small dams with careful consideration of ecological and social impacts can do better. In permanent rivers, under water beams are an option. In ‘wadis’ sand dams are a sound technology for the infiltration of river water to the groundwater.
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3. ESTs Storage
Artificial recharge of ground water
Artificial recharge is appropriate for the augmentation of groundwater in aquifers. It may supplement the natural percolation. In seasonal climates Aquifer Storage and Recovery practices both the storage and the quality control that is
essential to maintain the quality of groundwater resources. Recharging can
take place from the surface or directly into sub surface layers.
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3. ESTs Storage
Rainwater harvesting ESTs
Rainwater runoff from roofs is stored in tanks to be used inside buildings. Stormwater from streets
and parks can be infiltrated or stored in ponds to provide water for trees, gardens and parks. Sand filters and constructed wetlands can be used for quality control.
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3. ESTs Storage
Storage of treated sewageEffluent from sewage treatment plants can be reused in surface waters as a source for urban water supply. Quality control is crucial.
The use of effluent for recharging groundwater is possible. Soil Aquifer Treatment technology prevents pollution by pathogens, nutrients and other contaminants.
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3. ESTs Storage
Priorities for storage solutionsIn an integrated perspective, efficient and sustainable storage and augmentation can best be realized by decision makers if they follow this sequence of options:1. First, realize the full potential of treated wastewater and rainwater options. 2. Then, use the potential of surface water options. 3. And then, turn to aquifer based ESTs as a third option. Over-exploitation and pollution of aquifers is a threat. Invisible impacts are hard to restore.
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3. ESTs Storage
Supply and distribution ESTs
1. Surface water abstraction
2. Groundwater abstraction
3. Water supply reservoirs (tanks)
4. Transfer of water
5. Single pipeline systems (one quality)
6. Dual pipeline systems (two qualities)
7. Water containers (bottles, tanks)
8. Centralised treatment systems
9. Point of use treatment systems
[Sourcebook Chapter 4.3]
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3. ESTs Supply
Water pipe systemsWater supply networks are advanced systems that require advanced maintenance regimes. Leakage, due to poor maintenance is a major problem. Often more than 50% of the piped water is lost. Capacity building and fund availability for maintenance are the first priorities.
Lowering night time pressure and a system of metering and billing water use above a basic level may be helpful but are not a final solution.
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3. ESTs Supply
Dual quality systemsA problem of central piped network supply, is the use of drinking water quality for non drinking purposes. In dual networks service water quality has it’s own network. Wrong connections can be avoided by different colours for different pipes. Dual systems at the building level only, avoid city networks.
Buildings should have a reliable technical department for maintenance and quality control. Rainwater or treated greywater can be used as
service water. Sizable tanks can cope with fluctuations in demand and supply. every drop
counts3. ESTs Supply
Wells, tanks and bottlesAt the neighborhood level, improving the quality and increasing the number of traditional wells can be a good environmentally sound technology.
In a situation of centrally collected drinking water from rivers or groundwater (boreholes), good quality water can be delivered by trucks to static tanks,
from where people can take water home in bottles or small
containers. every drop counts
3. ESTs Supply
Drinking water qualityHealth requires good quality drinking water. Centralized treatment systems can be improved and extended.
If drinking water of reliable quality is not available, proper treatment at the user level is an option.
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3. ESTs Supply
Priorities for supply solutionsUnder an integrated water resource management perspective, efficient and sustainable supply and distribution can best be realized by adapting priorities to decision-making based on the existing situation:1. In a traditional situation of wells, improving this supply system has priority. 2. If this is difficult and there is an immediate need, delivery by trucks is an option. 3. If there is a basis for financing and for
capacity building, piped water networks become feasible. Their development should go hand in hand with on-site systems for supply of drinking water and service water. every drop
counts3. ESTs Supply
Use and saving ESTs1. Waterless toilets (compost- and dry-)
2. Water saving toilets
3. Water saving urinals
4. Waterless urinals
5. Water saving taps
6. Water saving showerheads
7. Pressure reducers
8. Water saving household appliances
9. Economised water use: personal hygiene
10.Economised water use: cleaning & watering
[Sourcebook Chapter 4.4]
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3. ESTs Use
Waterless toilets
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3. ESTs Use
Waterless toilets need neither water nor sewers. They work on the basis of dehydration and composting. The resulting compost can be applied to the fields in urban agriculture. The right degree of humidity is crucial. They are often combined with urine separation. Vertical
ventilation pipes guarantee odour free operation.
Compost toilets require more space and
need more maintenance. Simple dry toilets are easier to use and cheaper. They need to be emptied every week.
Water saving in households
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3. ESTs Use
Drinking, cleaning, bathing, washing, toilet flushing. Combined water saving appliances lead to 43% savings in liter per person per day.
Water saving in green spaces
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3. ESTs Use
Parks and gardens ask a lot of water, especially in dry climates. Savings may result from replacing piped water by rainwater or treated wastewater.
The local government and NGOs can also give a good example demonstrating how attractive green spaces can be created with native species adapted to dry conditions.
Not only technology
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3. ESTs Use
The challenge is: “meeting increasing service demands without increasing water supplies” (UN -Habitat, Local Action for Global Goals, 2003).
This is not only a matter of technology but also of life style, water squandering practices in private and public buildings and in public open space.
Change asks for a carrot and stick approach:• tax incentives and levies, demonstration projects
• rules, standards and enforcement
Priorities for use & savingIn an integrated water resource management perspective, efficient and sustainable water use and saving can best be realized by decision makers if they combine strategies:1. In new developments water saving
ESTs should become part of design and planning strategies from the beginning. This includes strategies for maintenance. 2. In existing urban areas creating conditions is crucial: financial incentives, technical support, training of skilled labour, legal
support, new standards. 3. Demonstration projects can show the way in a process of learning by doing. every drop
counts3. ESTs Use
Reuse, recycle & disposal ESTs quality and treatment issues
1. Domestic rainwater use
2. On-site treatment of grey water
3. Constructed wetlands
4. On-site and near-site treatment of black water and mixed sewage
5. Separating rainwater from sewer systems
6. Environmentally sound centralized sewage treatment in developing countries
[Sourcebook Chapter 4.5]
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3. ESTs Reuse
Rainwater quality and use
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3. ESTs Reuse
Roof-top rainwater only needs minor treatment to make it safe for service water. For use as drinking water, filtration and disinfection is required. There should be no debris in the tanks and no light. Quality control is a must.
Rainwater quality and use
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3. ESTs Reuse
Run-off rainwater from streets and open spaces can be treated in wetland systems. Separating rainwater from the sewers greatly improves the city treatment plant’s performance.
Grey & black water treatment
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3. ESTs Reuse
Household based decentralised ESTs deserve more attention. They create conditions for reuse at the domestic level and save costs for sewage systems.
Grey & black water treatment
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3. ESTs Reuse
Small scale aerobic (>compost) or anaerobic technology (>methane + slurry) are feasible. These innovative ESTs require careful and skilful guidance. For example joint projects of users with researchers and practitioners in a learning by doing context.
Example for on-site sewage treatment
Constructed wetlands
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3. ESTs Reuse
Stabilisation ponds and constructed wetlands are a low-cost alternative for the treatment of domestic wastewater. They provide water for irrigation in urban agriculture and for watering green spaces.
Detention and retention ponds, lined up with reeds and other wetland plants, perform well in purifying run-off rainwater from quite streets. More polluted water requires constructed wetlands designed for horizontal or vertical flow, filtering, adsorption and uptake of nutrients. Good design and maintenance are vital.
Advanced primary treatment
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3. ESTs Reuse
Increasingly strict standards, derived from the situation in developed countries have made it almost impossible to reuse effluent and sewage sludge in peri-urban agriculture. In developing countries effluent (from domestic wastewater treatment) usually contains less heavy metals and other toxic substances and more pathogens.
Advanced Primary Treatment (APT) is a new technology that combines primary (mechanical) treatment with filtration and disinfection. This opens healthy and water efficient perspectives.
Priorities for reuse, recycling & safe disposal
Under an integrated water resource management perspective, the choice of reuse, recycling and safe disposal options follows these priorities:1. Pollution prevention goes first. Roof-top rain- water and water from wells should retain drinking water quality. 2. In urban situations with an existing piped network, on-site rainwater and grey water treatment for service water should have priority in quality management strategy. 3. Reuse and recycle should have priority in wastewater treatment both at a centralized and decentralized level.
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3. ESTs Reuse
Integrated options and cases
[Sourcebook Chapter 5]
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4. Integration
EST-priorities for storage (and augmentation), supply (and distribution), use (and saving) and reuse & recycling (and safe disposal) have to be integrated in locally ‘promising combinations’.
This integration depends on the potential of the local situation (climate, hydrology, city-landscape)
‘Promising combinations’ also greatly depend on institutional capacity and the development stage. Five ‘guiding models’ illustrate these aspects. A given decision situation may be close to one of them. In a larger urban area, the guiding models may guide the making of a zoning model for the city, with specific strategies for each zone.
Village model
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4. Integration
development stageTraditional simple systems, self organisation, minor role for central government.promising EST combinations:Preferably ESTs based on groundwater, supported by traditional rainwater based ESTs.First option is water supply by wells. Residents take water home in small containers. Demand is usually < 30 liter per person per day.First options for sanitation are dry toilets and improved pit latrines to avoid groundwater contamination. Grey-water gardens or soil aquifer treatment for waste water discharge. Compost for agriculture.
storage
supply
use
reuse & recyclin
g
Squatter area model
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4. Integration
development stage Many new arrivals, short-term urgency and possible roles of central relief organisations for organising collective water and sanitation systems. promising EST combinations:Preferably ESTs based on groundwater or river. Central supply by trucks to static tanks. Residents take water home in small containers. Demand is usually < 30 liter per person per day.First trench latrines followed by improved pit latrines and dry toilets to avoid groundwater contamination. Starting with simple soakaways for waste water. Followed by grey-water treatment ESTs.
supply
use
reuse & recyclin
g
storage
Urban village model
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4. Integration
development stage Squatter area (favela, bidonville) on a more permanent basis. Increasing role of government agencies and NGOs. Upgrading. promising EST combinations:ESTs based on groundwater, if feasible, small dam in river. Promotion of rainwater harvesting ESTs.Piped water network that supplies collective tap stands, Quality control by agency. Introduction of dry toilets and compost collecting system. Support for rainwater use in households.Grey water treatment with irrigation and soil aquifer treatment.
supply
use
reuse & recycling
storage
City model
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4. Integration
development stage Existing medium to large cities, important role for government agencies, few collective and individual user based systems.promising EST combinations:Groundwater recharge, small dams in rivers. If big dam exists, alternatives reduce dependency. Strong promotion of rainwater harvesting ESTs.Full piped network. Priority for leakage control. Promotion of water saving toilets and water saving appliances. Water sensitive urban design to create conditions for run-off use for watering parks and gardens.Improving centralised wastewater treatment. Reuse of effluent and sludge in agriculture. Reuse of treated wastewater in watering green spaces.
supply
reuse & recyclin
g
storage
use
New town model
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4. Integration
development stage New development with a leading role for agencies, NGOs and developers. Collective organisations and individuals take over after construction. promising EST combinations:Groundwater or surface water based systems. Building design regulations and legal frame creates good conditions for rainwater harvesting. Full piped network for drinking water. Collective and individual systems for service water. Water saving and dry toilets, water saving appliances. Water sensitive urban design for run-off use in green spaces. Centralised and collective blackwater treatment. Building level grey water treatment (service water). Constructed wetlands in urban design.
supply
use
reuse & recyclin
g
storage
Questions for a specific case
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5. Questions
The sourcebook presents backgrounds (policies, criteria), a toolkit of ESTs, and illustrative cases. Moreover, the different chapters present questions that can be used in the planning process of a specific case. The model of the planning cycle (slide 22., sourcebook 3.4) shows the sequence of the questions in relation to the steps in the strategic stage of planning.
In this way, the questions may structure a workshop that generates alternative plans.
Wisewater is a supplementary tool for calculating the water saving potential of ESTs in the planning process.
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5. Questions
EVALUATION
efficiency
fit
initiative
strategic plan
• lessons from other local projects
• strenghts and weaknesses of this situation (SWOT)
(sourcebook chapter 3.4)
• questions about ‘sustainable’ (sourcebook 3.3)
• questions about flows, areas and actors
(sourcebook 4.2.2, 4.3.2, 4.4.2, 4.5.2)
• wich models come close? (sourcebook 5.2.3)
• Which ESTs form a ‘promising combination’ ?
(sourcebook 5.2.3, chapter 4)
ORIENTATION
GUIDING PRINCIPLES
ANALYSIS
EXAMPLES
GUIDING MODELS
Workshop questions
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…every drop counts twice…the joy and inspiration of planning with water
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