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Every drop counts. Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency. Presentation of key issues and tools. Every drop counts presentation.
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Every drop counts Environmentally Sound Technologies (ESTs) for urban and domestic water use efficiency Presentation of key issues and tools
Every drop countspresentation Delft University of Technologyproduction 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 Introduction Backgrounds of decision making Policies, Criteria Environmentally Sound Technologies Storage, Supply, Use, Reuse & Recycling Integrated options and cases Questions for a specific case every drop counts
1. Introduction every drop counts Objective and target group objective • 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 target group
1. Introduction every drop counts Scope and focus scope • 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 • Efficientandfit : technologies that fit in with sustainable perspectives for the local situation focus
1. Introduction every drop counts Sourcebook, presentation and WiseWater training module sourcebook • 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 presentation WiseWater
technology economy institutions 2. Backgrounds Policies every drop counts Policies and institutions [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.
2. Backgrounds Policies every drop counts 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:
EmbeddednessInformal institutions, customs, traditions, norms, religion Institutional environment Formal rules of the game, property, water laws, bureaucracy GovernancePlay of the game, contracting, aligning governance structures with transactions Resource allocation and development Prices and quantities, incentive management 2. Backgrounds Policies every drop counts Policy, Rules and Use Introducing ESTs: • What does it imply ? • Policies ? • Project development ? • Implementation ? • Operation ? All these activities have to be considered in the context of the four layers of the institutional framework.
2. Backgrounds Policies every drop counts National Water Policy Policy addresses many activities: • 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.
diagnosis planning operation implementation 2. Backgrounds Policies every drop counts Local decision making Diagnosis as a basis for planning: • 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
2. Backgrounds Policies every drop counts Problems in planning and implementation Plans that fail: • 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.
2. Backgrounds Policies every drop counts Operation, economic and financial aspects Issues: • 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.
2. Backgrounds Policies every drop counts 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:
2. Backgrounds Policies every drop counts Environmentally sound water policies Summary of key issues: • Sustainable water management, a vital aspect ofeconomic development in poor regions. • The economic value of waterestablishes 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.
2. Backgrounds Policies every drop counts Environmentally sound water policies (cont.) • Gender issuesare crucial in water management, especially at the domestic level. • Expertiseis crucial. Foreign advisers may play a role but onlylocal 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:
2. Backgrounds Criteria every drop counts Criteria for decisions [Sourcebook Chapter 3] At 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:
2. Backgrounds Criteria every drop counts 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 latrines poor sanitation
2. Backgrounds Criteria every drop counts Learning from a case 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, thereis agroupof criteria called fit. They have to be specified for flows and areas and actors.
PLANET PEOPLE PROSPERITY (ecological) (social) (economic) sustainable is: - sound use and liveability • participation - fair sharing • gender - profit and development 2. Backgrounds Criteria every drop counts Specifying ‘fit’ criteria for local plans General criteria forsustainable plans Specific criteria for the local plan FLOWS which flows? choices made? AREAS which areas? choices made? ACTORS which actors, choices made? guiding principles How to make a sustainable water plan? guiding models
2. Backgrounds Criteria every drop counts 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
2. Backgrounds Criteria every drop counts The planning cycle EVALUATION ORIENTATION initiative GUIDING PRINCIPLES use maintenance starting document efficiency realization ANALYSIS > flows > areas > actors detailed design fit EXAMPLES GUIDING MODELS strategic plan Fit and efficiency in the planning cycle
2. Backgrounds Criteria every drop counts 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.
2. Backgrounds Criteria every drop counts 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.
reuse,recycle & disposal storage & augmentation supply & distribution use & saving Environmentally Sound Technologiesin the Urban Water Cycle 3. ESTs Intro every drop counts
3. ESTs Storage every drop counts Storage and augmentation ESTs [Sourcebook Chapter 4.2] Ponds and Reservoirs Artificial recharge of Groundwater Water Tanks Rainwater runoff in surface water Rainwater runoff in groundwater Rainwater runoff in tanks Effluent in surface water Effluent in ground water
3. ESTs Storage every drop counts Ponds and reservoirs Dams 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.
3. ESTs Storage every drop counts 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.
3. ESTs Storage every drop counts 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.
3. ESTs Storage every drop counts Storage of treated sewage Effluent 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.
3. ESTs Storage every drop counts Priorities for storage solutions In 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.
3. ESTs Supply every drop counts Supply and distribution ESTs [Sourcebook Chapter 4.3] Surface water abstraction Groundwater abstraction Water supply reservoirs (tanks) Transfer of water Single pipeline systems (one quality) Dual pipeline systems (two qualities) Water containers (bottles, tanks) Centralised treatment systems Point of use treatment systems
3. ESTs Supply every drop counts Water pipe systems Water 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.
Dual quality systems 3. ESTs Supply every drop counts A 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.
3. ESTs Supply every drop counts Wells, tanks and bottles At 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.
3. ESTs Supply every drop counts Drinking water quality Health requires good quality drinking water. Centralized treatment systems can be improved and extended. If drinking water of reliable quality is not available, propertreatment at the user level is an option.
3. ESTs Supply every drop counts Priorities for supply solutions Under 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.
3. ESTs Use every drop counts Use and saving ESTs [Sourcebook Chapter 4.4] Waterless toilets (compost- and dry-) Water saving toilets Water saving urinals Waterless urinals Water saving taps Water saving showerheads Pressure reducers Water saving household appliances Economised water use: personal hygiene Economised water use: cleaning & watering
3. ESTs Use every drop counts Waterless toilets 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.
3. ESTs Use every drop counts Water saving in households Drinking, cleaning, bathing, washing, toilet flushing. Combined water saving appliances lead to 43% savings in liter per person per day.
3. ESTs Use every drop counts Water saving in green spaces 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.
3. ESTs Use every drop counts Not only technology • 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
3. ESTs Use every drop counts Priorities for use & saving In 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.
3. ESTs Reuse every drop counts Reuse, recycle & disposal ESTs quality and treatment issues [Sourcebook Chapter 4.5] Domestic rainwater use On-site treatment of grey water Constructed wetlands On-site and near-site treatment of black water and mixed sewage Separating rainwater from sewer systems Environmentally sound centralized sewage treatment in developing countries
3. ESTs Reuse every drop counts Rainwater quality and use 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.
3. ESTs Reuse every drop counts Rainwater quality and use 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.
3. ESTs Reuse every drop counts Grey & black water treatment Household based decentralised ESTs deserve more attention. They create conditions for reuse at the domestic level and save costs for sewage systems.
3. ESTs Reuse every drop counts Grey & black water treatment Example for on-site sewage treatment 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.
3. ESTs Reuse every drop counts Constructed wetlands 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.
3. ESTs Reuse every drop counts Advanced primary treatment 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.