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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 counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

Mar 31, 2015

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Ciara Strudwick
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Page 1: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

Every drop countsEnvironmentally Sound Technologies (ESTs)for urban and domestic water use efficiency

Presentation of key issues and tools

Page 2: Every drop counts Environmentally 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

Page 3: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 4: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

every drop counts

1. Introduction

Page 5: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

every drop counts

1. Introduction

Page 6: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

every drop counts

1. Introduction

Page 7: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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.

Page 8: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 9: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 10: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 11: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 12: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 13: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 14: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 15: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 16: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 17: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 18: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 19: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 20: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 21: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 22: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 23: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 24: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 25: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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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

Page 26: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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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]

Page 27: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 28: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 29: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 30: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 31: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 32: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 33: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 34: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 35: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 36: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 37: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 38: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 39: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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.

Page 40: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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.

Page 41: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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.

Page 42: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 43: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 44: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 45: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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.

Page 46: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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.

Page 47: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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.

Page 48: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 49: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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.

Page 50: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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.

Page 51: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 52: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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.

Page 53: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 54: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 55: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 56: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 57: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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

Page 58: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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.

Page 59: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

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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

Page 60: Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools.

every drop counts

…every drop counts twice…the joy and inspiration of planning with water