26323 Water Resources and Environment Technical Note F.1 Water Conservation: Urban Utilities Series Editors Richard Davis Rafik Hirji WATER RESOURCES AND ENVIRONMENT TECHNICAL NOTE F.1 Water Conservation: Urban Utilities SERIES EDITORS RICHARD DAVIS, RAFIK HIRJI The World Bank Washington, D.C. Water Resources and Environment Technical Notes A. Environmental Issues and Lessons Note A.1 Environmental Aspects of Water Resources Management Note A.2 Water Resources Management Policy Implementation: Early Lessons B. Institutional and Regulatory Issues Note B.1 Strategic Environmental Assessment: A Watershed Approach Note B.2 Water Resources Management: Regulatory Dimensions Note B.3 Regulations for Private Sector Utilities C. Environmental Flow Assessment Note C.1 Environmental Flows: Concepts and Methods Note C.2 Environmental Flows: Case Studies Note C.3 Environmental Flows: Flood Flows Note C.4 Environmental Flows: Social Issues D. Water Quality Management Note D.1 Water Quality: Assessment and Protection Note D.2 Water Quality: Wastewater Treatment Note D.3 Water Quality: Nonpoint-Source Pollution E. Irrigation and Drainage Note E.1 Irrigation and Drainage: Development Note E.2 Irrigation and Drainage: Rehabilitation F. Water Conservation and Demand Management Note F.1 Water Conservation: Urban Utilities Note F.2 Water Conservation: Irrigation Note F.3 Wastewater Reuse G. Waterbody Management Note G.1 Groundwater Management Note G.2 Lake Management Note G.3 Wetlands Management Note G.4 Management of Aquatic Plants H. Selected topics Note H.1 Interbasin Transfers Note H.2 Desalination Note H.3 Climate Variability and Climate Change Copyright © 2003 The International Bank for Reconstruction and Development/THE WORLD BANK 1818 H Street, N.W., Washington, D.C. 20433, U.S.A. All rights reserved. Manufactured in the United States of America First printing March 2003 2 CONTENTS Foreword 5 Acknowledgments 7 Introduction 8 The Need for Urban Water Conservation 9 Governments in developing countries are increasingly reluctant to pay for new water supply infrastructure, Authors while water utilities are not able to meet O&M costs, Nico Versteeg and let alone development costs, from user charges. As a Janine Tolboom result, conservation is becoming an important alter- native approach. Technical Adviser Stephen Lintner Increasing Delivery Efficiency 10 In most developing countries, there are numerous Editor opportunities to reduce unaccounted-for water in ur- Robert Livernash ban water delivery systems. Production Staff Cover Design: Cathe Fadel Increasing End-Use Efficiency 14 Opportunities to improve end-use efficiency include Design and Production: installing water-saving devices, promoting low-water- The Word Express, Inc. use landscapes, or recycling water for applications that do not require potable water quality. Notes Unless otherwise stated, Policy Tools for Water Conservation 17 all dollars = U.S. dollars. All tons are metric tons. Policies for water conservation include integrated water resources management and programs by water sup- pliers such as metering, price incentives, rebates, in- Cover photo by formation and education, water-use regulations and Curt Carnemark, World Bank standards, and water-use audits. Urban scene, Thailand Assessing Water Demand and Conservation This series also is available on the Opportunities 22 World Bank website (www.worldbank.org). Successful projects are more likely to occur when water demand and conservation opportunities are assessed early in the project cycle. Hermanus--A South African Case Study 24 The town of Hermanus in South Africa provides an example of water demand management following an assessment of options for meeting increases in demand. Conclusion 27 Further Information 28 3 WATER RESOURCESANDENVIRONMENT · TECHNICAL NOTE F.1 Boxes 1. Detecting physical and administrative water losses 12 2. Effectiveness of UFW programs 13 3. Khayelitsha Pressure Reduction Project, South Africa 14 4. Examples of household water saving devices 15 5. Example of water-saving measures in industry 15 6. Examples of identifying feasible project options including rainwater harvesting 16 7. Reallocation of water as a result of integrated water resources management studies 18 8. Installation of service-connection water meters in Bangladesh 19 9. Increased water tariff in Bogor, Indonesia 20 10. Examples of information and education activities for water conservation 21 11. Water conservation and investment planning in Australia 23 Figures 1. Regional water use per capita by sector 9 2. The future cost of water 10 Tables 1. San Diego County water supply cost comparison 10 2. Comparative costs of water supply and augmentation alternatives presented by MWRA 11 3. UFW in selected cities 11 4. Composition of UFW in selected cities 12 5. Estimated water savings due to metering and charging by volume 18 6. Advantages/disadvantages of different price structures 20 7. The new water tariff in Hermanus, South Africa 24 8. Percentage change in water consumption, Hermanus, using November 1995-October 1996 as base year 27 4 WATER CONSERVATION: URBAN UTILITIES FOREWORD The environmentally sustainable development and priority in Bank lending. Many lessons have been management of water resources is a critical and learned, and these have contributed to changing complex issue for both rich and poor countries. It attitudes and practices in World Bank operations. is technically challenging and often entails difficult trade-offs among social, economic, and political Water resources management is also a critical de- considerations. Typically, the environment is treated velopment issue because of its many links to pov- as a marginal issue when it is actually key to sus- erty reduction, including health, agricultural tainable water management. productivity, industrial and energy development, and sustainable growth in downstream communi- According to the World Bank's recently approved ties. But strategies to reduce poverty should not lead Water Resources Sector Strategy, "the environment to further degradation of water resources or eco- is a special `water-using sector' in that most envi- logical services. Finding a balance between these ronmental concerns are a central part of overall objectives is an important aspect of the Bank's in- water resources management, and not just a part terest in sustainable development. The 2001 Envi- of a distinct water-using sector" (World Bank 2003: ronment Strategy underscores the linkages among 28). Being integral to overall water resources man- water resources management, environmental agement, the environment is "voiceless" when other sustainability, and poverty, and shows how the 2003 water using sectors have distinct voices. As a con- Water Resources Sector Strategy's call for using sequence, representatives of these other water us- water as a vehicle for increasing growth and re- ing sectors need to be fully aware of the importance ducing poverty can be carried out in a socially and of environmental aspects of water resources man- environmentally responsible manner. agement for the development of their sectoral in- terests. Over the past few decades, many nations have been subjected to the ravages of either droughts or floods. For us in the World Bank, water resources man- Unsustainable land and water use practices have agement--including the development of surface and contributed to the degradation of the water resources groundwater resources for urban, rural, agriculture, base and are undermining the primary investments energy, mining, and industrial uses, as well as the in water supply, energy and irrigation infrastruc- protection of surface and groundwater sources, ture, often also contributing to loss of biodiversity. pollution control, watershed management, control In response, new policy and institutional reforms of water weeds, and restoration of degraded eco- are being developed to ensure responsible and sus- systems such as lakes and wetlands--is an impor- tainable practices are put in place, and new predic- tant element of our lending, supporting one of the tive and forecasting techniques are being developed essential building blocks for sustaining livelihoods that can help to reduce the impacts and manage and for social and economic development in gen- the consequences of such events. The Environment eral. Prior to 1993, environmental considerations and Water Resources Sector Strategies make it clear of such investments were addressed reactively and that water must be treated as a resource that spans primarily through the Bank's safeguard policies. The multiple uses in a river basin, particularly to main- 1993 Water Resources Management Policy Paper tain sufficient flows of sufficient quality at the ap- broadened the development focus to include the propriate times to offset upstream abstraction and protection and management of water resources in pollution and sustain the downstream social, eco- an environmentally sustainable, socially acceptable, logical, and hydrological functions of watersheds and economically efficient manner as an emerging and wetlands. 5 WATER RESOURCES ANDENVIRONMENT · TECHNICAL NOTE F.1 With the support of the Government of the Nether- The Notes are in eight categories: environmental lands, the Environment Department has prepared issues and lessons; institutional and regulatory is- an initial series of Water Resources and Environ- sues; environmental flow assessment; water qual- ment Technical Notes to improve the knowledge ity management; irrigation and drainage; water base about applying environmental management conservation (demand management); waterbody principles to water resources management. The management; and selected topics. The series may Technical Note series supports the implementation be expanded in the future to include other relevant of the World Bank 1993 Water Resources Manage- categories or topics. Not all topics will be of inter- ment Policy, 2001 Environment Strategy, and 2003 est to all specialists. Some will find the review of Water Resources Sector Strategy, as well as the past environmental practices in the water sector implementation of the Bank's safeguard policies. useful for learning and improving their perfor- The Notes are also consistent with the Millennium mance; others may find their suggestions for fur- Development Goal objectives related to environmen- ther, more detailed information to be valuable; while tal sustainability of water resources. still others will find them useful as a reference on emerging topics such as environmental flow assess- The Notes are intended for use by those without ment, environmental regulations for private water specific training in water resources management utilities, inter-basin water transfers and climate such as technical specialists, policymakers and variability and climate change. The latter topics are managers working on water sector related invest- likely to be of increasing importance as the World ments within the Bank; practitioners from bilateral, Bank implements its environment and water re- multilateral, and nongovernmental organizations; sources sector strategies and supports the next gen- and public and private sector specialists interested eration of water resources and environmental policy in environmentally sustainable water resources and institutional reforms. management. These people may have been trained as environmental, municipal, water resources, ir- rigation, power, or mining engineers; or as econo- mists, lawyers, sociologists, natural resources Kristalina Georgieva specialists, urban planners, environmental planners, Director or ecologists. Environment Department 6 WATER CONSERVATION: URBAN UTILITIES ACKNOWLEDGMENTS The production of this Technical Note has been Macoun, David Hanrahan, and Hans-Olav Ibrekk supported by a trust fund from the Government of of the World Bank reviewed the draft Note. Ronald the Netherlands managed by the Environment De- Mckenzie of WRP Ltd, South Africa provided infor- partment of the World Bank. mation on the Khayelitsha project. This Note was drafted by Nico Versteeg and Janine Tolboom of DHV Water, the Netherlands. Andrew 7 WATER RESOURCES ANDENVIRONMENT · TECHNICAL NOTE F.1 INTRODUCTION Access to sufficient amounts of clean water is in- ing sectors--agriculture, industry, and municipal creasingly recognized as the critical resource prob- uses. lem in the 21st century. The World Commission on Water estimates that the world's use of water has The World Bank's 1993 Water Resources Manage- increased six-fold over the last 100 years, even ment Policy and the recent Water Resources Sector though the population has only tripled. It predicts Strategy place a high priority on encouraging and that, under current levels of demand, water usage assisting countries that are implementing demand will rise by 50 percent over the next 30 years. Three management. Failure to use economic and regula- billion people will live in countries that will have tory instruments to manage demand and guide al- less than 1,700 m3 water per capita--the recognized location often results in inefficiencies as well as level of water stress--by 2025. significant externalities--reduced flows for down- stream uses, pollution, and degraded ecosystems. The World Water Council's recently released vi- sion statement makes it clear that developing new This Technical Note is one in a series of Notes pre- sources of water will not be sufficient to meet this pared by the World Bank Environment Department. challenge. New sources will have to be coupled Note F.2 deals with water conservation in the irri- with wiser use of existing stocks of water through gated agriculture sector and is a companion to this water conservation measures, water reuse, con- Note. This Note discusses the importance of saving junctive use of surface and groundwater, and main- water in an urban context; presents both physical tenance of water quality, so that drinking supplies and administrative measures to conserve water by and other essential uses are not compromised. increasing delivery efficiency; describes measures Water conservation can be promoted by ensuring to conserve water though increasing end-use effi- that prices are set to re- ciency; discusses policy flect the scarcity value of tools that can be used to the water, by developing encourage water conser- and installing water-sav- vation; and presents the ing technologies, and by steps that can be adopted encouraging stakeholders to assess water demand to take responsibility for and conservation mea- water use. By promoting sures hand-in-hand. A the correct policies and case study for the South Af- techniques, there is con- rican town of Hermanus il- Bank siderable scope for effi- lustrates the combined ef- orld W ciency improvements in fect of implementing many by the three main water-us- of the tools for water con- Photo Water seller filling cart, Viet Nam. servation. 8 WATER CONSERVATION: URBAN UTILITIES THE NEED FOR URBAN WATER CONSERVATION Water is an increasingly scarce resource in many fossil-fueled power plants are the single largest in- countries, as competition among agricultural, ur- dustrial consumers, using large amounts of water ban, and industrial users becomes more common. for cooling. While most of the water used for in- Worldwide, agriculture is the single largest user of dustrial purposes is returned to the water cycle, water, accounting for about 69 percent of all use. chemicals and heavy metals often contaminate it, About 23 percent of water withdrawals supply the or its temperature is increased. Industrial use var- industrial and energy sectors, and just 8 percent are ies from less than 5 percent of withdrawals in many used for domestic or household use. Thus, water developing countries to as much as 85 percent in withdrawals for urban consumption are substantial, Belgium and Finland. The proportion of water used but are significantly smaller than those for agricul- for industrial purposes is often considered an indi- ture. Patterns of use vary greatly from country to cator of economic development. country, depending on levels of economic develop- ment, climate, and population size (Figure 1). For Currently, about 1.5 billion people lack access to example, in countries such as Kuwait and Zambia-- safe water. Given the predicted urban population with little industry or irrigated agriculture--house- growth rates, the demand for water supply to ur- holds use nearly two out of every three liters of water ban populations for domestic and industrial uses is consumed. expected to grow rapidly. However, there are ma- jor technical and financial difficulties in meeting Household water consumption tends to increase this increasing demand in developing countries. with rising standards of living. In the United States, Technical difficulties arise because a) the most ac- individuals typically use more than 700 liters each cessible sources have already been tapped; b) wa- day for domestic tasks, compared to the average of ter is allocated to other uses such as irrigation at 29 liters per head used in Senegal to meet house- much lower cost than for urban use; c) groundwa- hold needs. ter is exploited in a way that often exceeds replen- ishment (see Note G.1); and d) the quality of intake Industry uses water for cooling, processing, clean- water has frequently deteriorated due to pollution ing, and removing industrial wastes. Nuclear and (see Notes D.1­3). Financial difficulties arise as a consequence of these FIGURE 1. technical difficulties. The unit cost of raw water is REGIONAL WATER USE PER CAPITA BY SECTOR expected to at least double, and in some cases triple, 1000 in many cities as more distant and more costly Agriculture /yr) 900 sources of water supply have to be tapped. Figure 2 3 (m Industry 800 shows the projected unit cost of the next raw water supply scheme for a number of cities based on a 700 capita 1990 World Bank study. As pollution increases, the 600 per Municipal increase in the cost of delivering treated water could 500 tor be even greater once the increasing costs of treat- sec 400 ment are incorporated. These technical problems, yb 300 along with the generally poor performance of pub- use 200 lic water and sewage utilities--caused by problems tera such as unregistered connections, unaccounted-for 100 W water (UFW), and excessive numbers of employ- 0 Africa Asia North/Central South Europe Former USSR ees--mean that many utilities experience a low de- America America gree of cost recovery. The upshot is that governments 9 WATER RESOURCES AND ENVIRONMENT · TECHNICAL NOTE F.1 FIGURE 2. As the cost of bringing new sources on-line in- THE FUTURE COST OF WATER . creases, more efficient use of the existing supplies 1.4 becomes an increasingly cost-effective alternative More than double Amman to supply augmentation (see Table 1). This demand 1.2 More than triple management approach is termed water conserva- ) tion. For urban water utilities, water conservation 3 More than equal 1 Equal cost line can take several forms. Where transmission and dis- (US$/m 0.8 Mexico City tribution losses are high, actions could include leak ostc detection programs, rehabilitation of pipes, or pres- Hyderabad e 0.6 Lima sure reduction projects. Where demand is high, Algiers uturF 0.4 actions such as awareness-raising programs, price Dhaka incentives, and regulation may be effective. Com- 0.2 Banglaore pared to supply-based solutions, a demand man- Shenyang agement approach has the major advantage that it 0 0 0.2 0.4 0.6 0.8 1 1.2 1.4 is designed to promote sustainability by changing Current cost (US$/m3) public attitudes to water and water consumption over time. Source: World Bank 1992. World Development Report: Develop- ment and the Environment. Washington: World Bank. Notes. Costs are in 1988 $ and are for raw water, excluding treat- ment and distribution. Current cost is the cost at the time the data TABLE 1. were collected; future cost is the cost of a new development project. SAN DIEGO COUNTY WATER SUPPLY COST COMPARISON The most expensive example of current cost is Mexico City. Future investment costs per m3 in Amman and Hyderabad are expected Source Range ($ per 1,000 m3) a) to increase by a factor of about 4 compared to current invest- ment costs. Desalted Sea Water 973­1,612 Imported Water 566­670 Desalted Well Water 365­649 Reclamation b) 292­473 in developing countries are increasingly reluctant Conservation c) 162­567 to finance the rising costs of water supply infrastruc- Notes: ture, while water utilities are not able to meet costs a) Figures reflect 1990 costs. from user charges. Consequently, the water supply b) These costs are for water delivered to the end user. c) Conservation measures used in calculation include installation and sanitation sector in developing countries either of high quality water-conserving showerheads and ultra-low flush becomes increasingly dependent on the support of toilets. Source: San Diego County Water Authority. 1991. Economic and donors and international finance institutions or Financial Analysis, Clean Water Program for Greater San Diego, turns to the private sector for management. Phase 1 Water Reclamation Program, in World Bank (1993). INCREASING DELIVERY EFFICIENCY As utilities struggle to use older and poorly main- stressing causes movement of pipes and greatly tained water distribution systems to meet demand, increases leakage. Water conservation and, if nec- water supplies often become intermittent. Although essary, development of new water sources, is a more intermittent operation can conserve water in the sustainable solution. sense that empty pipes don't leak, this is not a de- sirable operational strategy, since the uncertainty Maintenance is likely to provide a cost-effective means is disruptive to consumers and can encourage them of water conservation where the supply system is old to use water inefficiently for the periods when it is and poorly maintained. For instance, the Massachusetts available. In addition, intermittent operation is dam- Water Resources Authority (MWRA) has determined aging to distribution networks because the cyclical that leak detection and repair is among the most 10 WATER CONSERVATION: URBAN UTILITIES TABLE 2. COMPARATIVE COSTS OF WATER SUPPLY AND AUGMENTATION ALTERNATIVES PRESENTED BY MWRA Alternative Annual Capital cost Yield ($ per 1,000 m3)a ($ million)b (1,000 m3/day) Supply Responses: Connecticut River 132­211 120­220 238 Millers/Tully Rivers 238 135 144 Merrimack River 423 600 454 Conservation and Demand Management: Leak Detection & Repair 37 30 114 Domestic Device Retrofit 61­148 10 19­45 Low-Flow Toilet Retrofit 872 200 64 Industrial & Commercial Conservation 13 0.1c 3c Improved Use of Existing Supplies: Local Sources 90­343 16 1.5­30 Water Sharing 13­132 0.2c 3c Sudbury Residential Treatment Plant 211 34­37 62 FY90 MWRA Water Rate 135 N/A N/A Source: Massachusetts Water Resources Authority. 1990. MWRA Long Range Water Supply Program, in World Bank (1993). Notes: a) Annual O&M and amortized capital costs. b) Figures reflect 1990 costs. c) Yields and costs from first year's experience. Actual values will be higher. economical means of balancing demand and supply TABLE 3. within their service area (see Table 2). UFW IN SELECTED CITIES Country, city Year Unaccounted-for A low rate of unaccounted-for water (UFW) is one Water (%) of the important overall indicators that a water sup- Brazil, Sao Paulo ply utility is successful. Rates of UFW vary from Metropolitan Area 1992 40 system to system. In 1994, Singapore's UFW of about Chile, Santiago 1990 28 Colombia, Bogota 1991 40 6 percent was the lowest in the world. In many other Costa Rica 1991 45 cities, rates of 20 to 40 percent are not unusual (Table Ivory Coast, Abidjan 1993 17 3). The amount of UFW in Mexico City's supply sys- Guinea, Conakry 1993 53 tem is sufficient to supply a city the size of Rome.1 Senegal, Dakar 1993 29 Clearly, there are major opportunities to put this Togo 1990 22 Turkey, Ankara 1988 45 wasted resource to productive use and thereby post- Pakistan, Karachi 1995/96 30 pone the need to develop new sources of water. China, Shanghai 1995 14 Philippines, Manila 1995 44 UFW includes two types of losses. Physical2 losses Thailand, Bangkok 1994/95 38 include water lost from leaks in the distribution Kyrgyz Republic, Bishek 1996 42 France, Bordeaux 1982 15 systems, in-house connections, and from overflows Canada (average) 1984 15 in distribution tanks. Administrative3 losses repre- USA (average) 1984 12 Japan, Tokyo 1990 12 Macao 1991 11 1Falkenmark, M., and G. Lindh. 1993. "Water and eco- Singapore 1994 6 nomic development," in P. H. Gleick. 1993. Water in Cri- Sources: Asian Development Bank. 1997. Second Water Utilities sis: A Guide to the World's Fresh Water Resources. New Data Book, Asian and Pacific Region. Other data from World Bank York: Oxford University Press. (1996). 2Sometimes called technical losses. 3Sometimes called non-technical or commercial losses. 11 WATER RESOURCES AND ENVIRONMENT · TECHNICAL NOTE F.1 TABLE 4. COMPOSITION OF UFW IN SELECTED CITIES Country/City Year Composition of UFW (%) Physical Administrative Total Singapore 1989 4 7 11 Spain, Barcelona 1988 11 12 23 Colombia, Bogota 1991 14 26 40 Costa Rica, San Jose 1990 21 25 46 Source: World Bank (1996). sent water used but not paid for. They stem from There are several means available to detect and unauthorized use of water (illegal connections), estimate UFW. The most important measures are from faulty meters, and from tampering with the discussed in Box 1. often-inadequate controls of the commercial sys- tem. Administrative losses often constitute a major The goal should not be to completely eliminate portion of UFW (Table 4). UFW, but rather to reduce it to a point where fur- BOX 1. DETECTING PHYSICAL AND ADMINISTRATIVE WATER LOSSES Physical Administrative Estimating amounts of leakage Under-measurement of consumption For those systems supplying water 24 hours per day, To reduce the under-measurement of consumption, a "nightflow measurement" provides a relatively straightfor- list could be prepared of those properties whose ward way to obtain an estimate. This involves measuring metered consumption seems suspiciously low com- rates of water flow into the distribution network at night, pared to earlier records or to the metered consumption when actual water consumption by customers is very of their neighbors. The meters on those properties could low. This approach does not work where water consump- then be inspected to check for any signs that they have tion may be considerable during the night, e.g. for filling been tampered with and/or that they need cleaning or ground or roof tanks. If those customers who use signifi- repair. cant amounts of water during the night are known to the water utility, their consumption may be estimated. Leak- Meter reading and recording losses age from the distribution system can be estimated once Other major causes of administrative losses can be these demands are taken into account. incompetence, inadequate training, and/or corruption of meter readers. These problems are more common Locating the points of leakage (leakage detection) where poorly paid meter readers also collect the water Various methods for leakage detection are available: bills. Ways to improve meter reading include better pay 1. Visual inspection. A stroll around the area served by and incentives for staff, appropriate training, frequent the distribution network, especially in the dry season, verifications by supervisors, and regularly changing of will usually reveal a number of sources of leakage. routes covered by individual readers. Contracting out Wet patches of earth, over or alongside the routes of meter reading is also becoming more frequent. Modern pipelines, frequently indicate underground leaks. methods of meter reading by hand-held computers or 2. Step-testing. This method can only be carried out remote metering generally overcome these problems. where bulk water meters are installed. The technique of step-testing involves shutting off the supply to parts of Non-registered connections the study area in consecutive steps by using "step valves." The extent to which the utility can check for illegal 3. Listening for leaks. When water, under pressure in a connections is determined by local custom and pipe, is allowed to escape through a small hole or practice. In some countries, a group comprising crack, often it will produce a particular hissing sound. government officials/elected leaders periodically visits The sound travels both through the ground and along and inspects properties suspected of having illegal the pipe. It is often possible to detect leaks merely by connections. listening for them. Leak noise correlates can pinpoint the location of the leak. 12 WATER CONSERVATION: URBAN UTILITIES ther benefits equal additional costs. This point will depend, among other things, on the relative scar- city value of water. As discussed in Note F.2, leak- age from irrigation water distribution systems of- ten supports beneficial uses (such as village water supply, groundwater recharge, and wetlands), so the Africa correction of leaks in these supply systems should South, only be undertaken after a thorough analysis of the Ltd benefits and costs arising from leak reduction. How- WPS, ever, these considerations are much less important enzie in urban water supply systems, where there are Mck.R fewer beneficial uses for leakage water. Conse- by quently, there are greater net benefits from leak re- Photo ductions programs in urban water distribution sys- Khayelitsha pressure reduction plant, South Africa. tems. Box 2 presents two case studies showing the cost-effectiveness of UFW programs in two differ- ent circumstances. addition to the R27 million saved in reduced water use. To date, there have been no incidents of van- Leaks in both the distribution system and within dalism or damage to the installation. These results households can be exacerbated by excessive water can be largely attributed to the high degree of com- pressure. Where this occurs, reducing the pressure munity involvement in the whole pressure reduc- can produce highly cost-effective results, as is shown tion project, including the use of local labor in the case of Khayelitsha in South Africa (Box 3). wherever possible. Not only was the original water use reduced by 43 percent, but the capital investment was paid off Asset management is increasingly being recognized within the first two months of operation through as an essential function of water utilities. This fo- reduced water use, and there were few complaints cus derives not only from the need to meet regula- from the community over the reduced water pres- tory requirements, but also from the need to sure. Additional savings occurred in the sewage produce long-term investment plans and to target treatment plants. The planned upgrade of the capital expenditure in the most cost-effective man- Zandvleit Sewage Treatment Plant, which had a ca- ner. Most urban water utilities have a wide range pacity of 60 ML/day and was running over capac- of assets, such as sources, reservoirs, treatment ity, was dropped because inflows to the plant were works, water mains, pumping stations, and mis- reduced by 20 Ml/day. The postponement of the up- cellaneous offices, depots, and workshops. For ef- grade is estimated to save R4.5 million per year in fective management of these assets, it is essential BOX 2. EFFECTIVENESS OF UFW PROGRAMS The city of Murcia, Spain, with a population of 350,000 was faced with a high UFW level of 44 percent. By implement- ing a new commercial management system that better accounted for all water uses and users, the municipal company reduced unaccounted-for water to 23 percent over five years. The resulting water savings proved adequate to increase the number of water connections by 19,000 and achieve 100 percent coverage. The city-state of Singapore, with a population of about 2.8 million, has scarce water resources. By sustaining a consistent metering and leak reduction program, the Public Utilities Board has succeeded in reducing UFW from the already low level of 10 percent in 1989 to 6 percent in 1994. In this case, the high value of freshwater makes a low UFW economically worthwhile. Source: Adapted from Yepes, G. (1995). 13 WATER RESOURCES AND ENVIRONMENT · TECHNICAL NOTE F.1 BOX 3. KHAYELITSHA PRESSURE REDUCTION PROJECT, SOUTH AFRICA Khayelitsha, approximately 20 km from Cape Town, is one of the largest townships in South Africa. The area houses approximately 450,000 people in 43,000 serviced sites with both internal water supply and waterborne sewage, and a further 27,000 squatter shacks supplied from communal standpipes. The area is supplied with potable water from Blackheath Reservoir--situated at an elevation of 110 m--through two large water mains of 450mm and 1,065 mm diameter. The average head at the supply point is approximately 80m, which is excessive and has caused consider- able damage to household plumbing fittings. The minimum night flow (MNF) was 1,600 m3/hr. Approximately 1,200 m3/hr were leaking to the sewer system, indicating that the key problem was household leakage. The Khayelitsha Pressure Management Project was initiated in June of 2001 by the City of Cape Town to reduce the excessive water pressure in the reticulation system. In a first phase, pressure reduction valves (PRVs) were inserted into the water supply mains to reduce pressure. In the second phase, advanced electronic controllers were installed to manipulate the pressure during off-peak periods. Through the use of such controllers, it is possible to achieve larger savings than those obtained through the PRV's on their own. The results were dramatic. Prior to the project, the average daily flow was 2,500 m3/hr (21 million m3/a, of which 75 percent was wastage) with a minimum night flow of 1,600 m3/hr. After the first phase was completed, the average daily flow was reduced to 1,790 m3/hr and the minimum night flow to 1,180 m3/hr. The implementation of the second phase was to be completed by the end of 2002. Although final outcomes of Phase 2 have not been fully compiled, preliminary results achieved so far indicate that the MNF has been reduced by a further 430 m3/hr (to 750 m3/hr). The initial results suggest that the eventual savings will be in excess of 9 million m 3/yr out of the original 21 million m3/yr. Source: Mckenzie, R.S. 2002. "Khayelitsha Leakage Reduction Through Advanced Pressure Control, MIESA Monthly Magazine, Journal of the Institution of Municipal Engineering of Southern Africa, 27 (8): 43-47. to know what assets are available, what they are the investment required to maintain acceptable meant to do, what condition they are in, and how levels of service and UFW, while controlling costs they are performing. With this information, the and understanding the trade-offs between invest- water utility is able to make informed decisions on ment and business risks. INCREASING END-USE EFFICIENCY While the previous measures focused on conserv- household water-saving devices and industrial ing water by reducing losses in the water distribu- water savings may contribute to water savings in tion system, this section focuses on conserving water those developing countries where there is already through increasing end-use efficiency. End-use effi- an extensive reticulated water supply system and ciency is the amount of service obtained per unit of where the economy is sufficiently robust to allow water used. Within the urban context, end-use effi- the installation of water-saving devices. Low-wa- ciency can be increased for water use in households ter-use landscaping and multiple uses of water are and gardens or parks, or in industrial water use. included here because they may be applicable in specific instances in developing countries. The four techniques described here have been pio- neered in those parts of developed countries--such WATER-SAVING DEVICES as the southwestern United States--that experience water shortages. They are less relevant to the de- Water-saving devices can provide the same service veloping world, where reductions in water con- using less water by restricting flow to increase the sumption are more likely to occur through velocity of discharge. Some useful examples of com- increasing water delivery efficiencies. However, mon water-saving devices for households in indus- 14 WATER CONSERVATION: URBAN UTILITIES BOX 4. EXAMPLES OF HOUSEHOLD WATER SAVING DEVICES - Plumbing. Residential water users can conserve water by installing indoor plumbing fixtures that use less water. Low-flow plumbing fixtures and retrofit programs are permanent, one-time conservation measures that can be implemented automatically with little or no additional cost over their useful lifetimes. In some cases, they save the resident money over the long term. Low-flush toilets. A traditional toilet is often the biggest water-using fixture in houses in developed countries. Ultra-low- flush toilets are required in new construction in many jurisdictions. Some water districts offer rebates to those homeowners who refit their homes with ultra-low-flush toilets. If toilet replacement is not possible, homeowners can conserve water by placing a brick, a stone, or a plastic bag or container filled with water in the toilet tank. This dis- places some of the water and reduces the amount of water per flush. Low-flow showerheads. After the toilet, the biggest household water user is the shower or bathtub. A shower-flow restrictor can cut the flow to less than half the normal flow. A low-flow showerhead offers even greater savings. Properly designed low-flow showerheads are available to provide the quality of service found in higher-volume models. Faucet aerators. Faucet aerators, which break the flowing water into fine droplets and entrain air while maintaining wetting effectiveness, are inexpensive devices that can be installed in sinks to reduce water use. Aerators are easily installed and may reduce the water use at a faucet by as much as 60 percent while still maintaining a strong flow. Pressure reduction. Because flow rate is related to pressure, the maximum water flow from a fixture operating on a fixed setting can be reduced if the water pressure is reduced. Homeowners can reduce the water pressure in a home by installing pressure-reducing valves. The use of such valves is one way to decrease water consumption in homes that are served by municipal water systems. For homes served by wells, reducing the system pressure can save both water and energy. A reduction in water pressure will have no effect on fixtures such as washing machines and toilets that operate on a controlled amount of water. A reduction in water pressure may also help reduce flows from leaking water pipes, leaking water heaters, and dripping faucets. Source: US EPA. 2000. Using Water Efficiently: Ideas for Residences. Washington: USEPA trialized countries are provided in Box 4. These wa- saving measures can be implemented in industries, ter-saving devices may not be appropriate in devel- businesses, and institutions. In these cases, identi- oping countries because of low levels of water use, fying water-saving measures may be less straight- cultural values, or restricted income levels. Water- forward and may require specialist studies (Box 5). BOX 5. EXAMPLE OF WATER SAVING MEASURES IN INDUSTRY - The Massachusetts Water Resources Authority conducts water efficiency studies as part of its Industrial/Commercial/ Institutional Water Management Program. The purpose of the program is to analyze water use in industrial facilities and identify cost-effective water efficiency measures that result in a payback on investments in roughly two years. MicroSemi is an example of a company that has benefited from this program. The report provided by the MWRA proposed the following measures: I replacing two of the filter membranes in the water purification system I utilizing reject streams from the purification system for cooling-tower makeup I reducing nonproduction-period losses (through increasing employee awareness) I reducing rinse-water consumption. When MicroSemi managers realized the long-term cost effectiveness of these measures, they wanted to go beyond the proposed measures and decided to upgrade the entire water treatment system. With an investment cost of $135,000, estimated water savings amounted to about 14 million m3 per year. The estimated water, sewer, and heating savings were $55,600 in 1994. Source: MWRA. 1994. Water Use Efficiency Case Study: MicroSemi USPD Inc., Watertown, MA. 15 WATER RESOURCES AND ENVIRONMENT · TECHNICAL NOTE F.1 LOW-WATER-USE LANDSCAPE Derived from the Greek word "xeros" for dry, xeriscape combines creative functional landscap- Bank ing, efficient irrigation, and water-thrifty plants to orld W, save water. Examples include grouping plants with similar water requirements and adjusting the wa- Mercier tering schedule for each area of the yard. Such oget grouping prevents water from being wasted on Jean-R plants that do not need it. Because grass uses con- by siderable water, another technique is to use grass Photo only when appropriate or useful, filling in other River, Colombia areas with attractive, water-thrifty groundcovers, perennials, and shrubs. Such measures may be gation needs of a domestic dwelling in a semiarid taken at different locations, such as homes, hotels, region. Grey water can also be used for toilet flush- government agencies, or industries. ing if the country's regulations on reuse of water and cultural beliefs allow. MULTIPLE USES OF WATER Rainwater can be collected or harvested from paved Some urban water uses, such as toilet flushing or areas, roofs, or gutters. Houses can be designed to irrigation of gardens, do not require potable qual- maximize the amount of catchment area, thereby ity water. Grey water4, rainwater, surface water, or increasing rainwater-harvesting possibilities. Col- treated wastewater could be used instead, yielding lected and stored rainwater can be used in toilet water savings and possible cost reductions. flushing and surface irrigation, especially in gardens where food is grown. In the United States, harvested Grey water is most suitably used for subsurface ir- rainfall is used mainly for irrigation and occasion- rigation of nonedible landscape plants. Grey water ally for other domestic uses. Rainwater harvesting could supply most, if not all, of the landscape irri- systems can be quite simple and inexpensive. Di- recting rainfall to plants located at contoured low 4Grey water is derived from residential water uses such points is a very simple rainwater harvesting system. as the bath, shower, washing machine, and bathroom sink, More complex systems include storage of rainfall. which do not contain human wastes. Water flushed from Box 6 includes an example of a project where rain- toilets, where bacterial contamination may occur, is called water harvesting techniques were included as an black water. alternative urban water supply option. BOX 6. EXAMPLES OF IDENTIFYING FEASIBLE PROJECT OPTIONS INCLUDING RAINWATER HARVESTING Three Indonesian villages, included in a water supply project, face poor groundwater quality and dry dug-wells in the dry season. Rainfall, on the other hand, occurs reasonably frequently. The least-cost analysis included the following options: I rainwater collection (with storage) I hand pumps, small bore well I hand pumps, small bore well with upflow filter units I piped water supply system. By including all these options in the consideration of alternatives, the analysis explored not only conventional water supply approaches, but also an option that would help conserve traditional water supply sources. Source: Asian Development Bank (1999). 16 WATER CONSERVATION: URBAN UTILITIES POLICY TOOLS FOR WATER CONSERVATION The previous two sections described the adminis- of water-saving devices. The following sections dis- trative and physical measures to increase delivery cuss specific tools that can be used by water sup- efficiency and end-use efficiency. This section dis- pliers and governments in the implementation of cusses policy tools for water conservation. Some of urban water conservation programs. the tools (e.g. higher unit prices for water supply) provide incentives to implement water saving mea- Metering. Metering is a fundamental tool for water sures; others make better use of existing sources of system management and conservation and a pre- urban water supply. Other policy tools, such as requisite for efficient pricing systems. It provides mandatory rationing that rely on regulatory pow- information on the delivery efficiency of the water ers, are not discussed here. system and offers incentives to consumers for wa- ter conservation. INTEGRATED WATER RESOURCES MANAGEMENT Metering can be installed at different locations and for different purposes: I Source-watermetering.Boththesupplierandthe An integrated approach is widely agreed to be the customer benefit from these installations. Source most effective way of managing water resources so metering is essential for water accounting pur- that the demands from all water users, including poses. the environment, are taken into account. Higher- I Service-connectionmetering.Service-connection level government institutions may have opportuni- metering informs customers about the quantity ties to implement measures that improve or alter of water they are using. Suppliers can use these the management and allocation of water resources, metering data to track water usage. Such me- thus resulting in more efficient use of the resource. tering is essential if consumer charges are to For example, better management of source areas be based on the amount of water consumed. can improve both quantity and quality of water sup- I Public-usewatermetering.Allwaterprovidedfree plies, and thus postpone development of costly new of charge for public uses can be metered. This sources of water. will allow the utility to account more accurately for water use. Lack of public-use metering un- Box 7 provides two examples where the costs and dermines other conservation measures. benefits of water use by multiple sectors were con- sidered in an integrated way. In Song Quao, Viet Service-connection metering in combination with Nam, water quantities were allocated among sec- charging by volume can result in significant water tors in order to maximize the benefits from the avail- savings (Table 5). However, service-connection able water. In Liaoning Province, China, metering requires considerable capital cost. Meter inter-sectoral water quality improvements were testing, calibration, repair, and maintenance pro- identified that would lead to better water use. Inde- grams are fundamental to ensure accurate water pendent decisions in each sector would not have accounting and billing. This is feasible when the resulted in economically optimal decisions. country has sufficient technical capacity to main- tain this technology over the long term. Box 8 de- PROGRAMS BY WATER SUPPLIERS scribes the experience of installing water meters in two towns in Bangladesh, accompanied by a pub- Specific conservation measures are seldom executed lic education program. effectively in isolation. For example, tariff increases, supported by education and backed by legislation, Price Incentives. Water-user charges are often con- are likely to be more effective in promoting the use sidered a central component of a water conserva- 17 WATER RESOURCES AND ENVIRONMENT · TECHNICAL NOTE F.1 BOX 7. REALLOCATION OF WATER AS A RESULT OF INTEGRATED WATER RESOURCES MANAGEMENT STUDIES Song Quao, Viet Nam The opportunity cost of obtaining municipal water supplies during the dry season (December to May) from the Song Quao irrigation scheme was determined for various crops. The opportunity cost was calculated at $0.081 per m3, of which $0.102 per m3 was for sugarcane, $0.197 per m3 for rice in the double rice system, $0.062 per m3 for rice in the triple rice system, and $0.029 per m3 for watermelon. To maximize overall net benefits from these scarce water resources, the crops with the lowest net benefit per m3 should be removed first, followed by crops with the next higher benefits, and so on. This meant that all 50 ha of watermelon should be replaced with nonirrigated crop cultivation, and an increasing part of the triple rice system should be taken out of production to meet the need for municipal water supply (117 ha for a piped water supply of 15,000 m3/day, 178 ha for 20,000 m3/day, and 299 ha for 30,000 m3/day). The opportunity cost of raw water was estimated at $0.060 per m3 based on these crop areas. These reductions in agricultural production meant that the cost of reallocating water from irrigation to urban water supply would be about $37,000 per year for the production of 7,000 m3 of drinking water per day, $113,000 for 15,000 m3 of drinking water per day, $168,000 for 20,000 m3 of drinking water per day, and $277,000 for 30,000 m3 of drinking water per day. Liaoning Province, China Liaoning Province, in the northeast part of China, has a total land area of 145,700 square kilometers and a population of about 36 million, including some 25 million in urban areas. The province has a strong urban industrial base, but relies on farming for its basic food supply. The most important farm production areas are the twin basins of the Hun and Taizi rivers in the center of the province. Water supply for industrial, domestic, and agricultural purposes is heavily dependent on flows from the two rivers, either from direct extraction or from groundwater recharge. Rapid industrial development combined with inadequate wastewater management has heavily polluted both surface and groundwater resources, seriously affecting drinking, industrial, and agricultural water quality. There is an urgent need to raise the quality of the water in the two rivers to a standard that makes it safe for both human and environmental use, while being economically justifiable. Strategies for the effective utilization of the Hun-Taizi water resources were identified through a study completed in 1988. The study identified investments required for water resource development and water pollution abatement in specific cities. Furthermore, the study highlighted deficiencies in institutional arrangements for water resource manage- ment, inadequate urban environmental services, and the need for focused water and wastewater investments. The Liaoning Environment project assists the government in reducing pollution and improving operational efficiency through upgrading of technology, minimization of waste, and reuse of resources. TABLE 5. ESTIMATED WATER SAVINGS DUE TO METERING AND CHARGING BY VOLUME Location Period Savings due to metering (%) Collingwood, Ontario, Canada 1986­90 Summer peak: 37 Leavenworth, Washington, USA 1988­91 Summer peak: 61 Oak Park, UK 1993­96 Summer peak: 50 New York City, USA 1991­95 Annual: 7 Portland, USA 1993­94 Annual 10-12 Isle of Wight, England 1988­92 Annual: 21 Barcelona, Spain early 1990s Annual: 13 St Peter's, UK 1993­96 Annual: 14 Source: Organisation for Economic Co-operation and Development (OECD). 1999. Household Water Pricing in OECD Countries. Paris: OECD. 18 WATER CONSERVATION: URBAN UTILITIES BOX 8. INSTALLATION OF SERVICE CONNECTION WATER METERS IN - BANGLADESH The objective of this water supply and sanitation project was to improve the performance of water supply utilities in 18 district towns in Bangladesh. As a pilot project, water meters were installed in two towns, each with about 75,000 inhabitants in order to increase the water revenue collection efficiency. Through an education program, the public was informed that: I Water supply was going to be improved: more supply hours; more value for money. I Potable water is precious, so consumers have to pay for what they use. I The tariff system will change; instead of a flat rate, consumers will pay for what they use. Water meters will be installed to measure the usage. I Procedures will be implemented for the water meters, including water meter reading, billing, and other responsibilities. Local nongovernmental organizations (NGOs) distributed this information to the public via leaflets, announcements in public places, door-to-door surveys, and letters to individual customers. The program was successful, with collection efficiency increasing. However, customers were less interested in the water-saving aspects of the program than the use of the meters to justify their payments. tion strategy. If water consumption is metered, then line" quantity) at a subsidized price. If these pre- price can be used to modify water demand. cautions are taken, increasing the price of water can allow the utility to enter into new service areas, The price elasticity of demand measures the respon- thereby increasing rather than decreasing equity. siveness of demand to changes in price. It varies between countries, types of water users, and sea- From an economic efficiency point of view, the price sons. A price elasticity of ­0.5 implies that if price charged for water should equal the long-run mar- increases by 10 percent, demand decreases by 5 ginal cost. In practice, achieving full financial cost percent. Typically, price elasticities for domestic recovery can be a major step forward in both de- consumers lie between ­0.2 and ­0.8; typical val- veloping and developed countries. ues for industrial consumers lie between ­0.5 and ­1.3.5 There are various water pricing structures, such as increasing or declining block rates, seasonal or Increasing the price of water is invariably a politi- peak rates, flat rates, and concessional rates for new cally sensitive issue. One of the common arguments users. Table 6 shows the general advantages and for opposing price increases is that higher prices disadvantages of each structure, although the ac- would prevent the poorer segments of the (urban) tual advantages/disadvantages should be assessed population from receiving essential water supplies. for each case. The validity of this argument is debatable. In many cases, the relatively richer segments of the popula- An increase in the price of water, accompanied with tion benefit from subsidized water supply, while the other measures, can lead to long-term water sav- poorer segments--often living in semi-urban areas-- ings (Box 9). are left unserved and depend on water vendors, who often charge many times the price of reticulated Household water demands are not evenly spread water. If the urban poor are dependent on reticu- over time. Household water demand changes sea- lated water, there are several ways to protect them sonally, as well as within the day and, to a limited against increases in the average price of water, such degree, within the week. Large costs will be faced as providing a minimum amount of water (a "life- if supply systems are to be constructed, maintained, and operated to satisfy the maximum peak flows experienced. 5See World Bank. 1996. 19 WATER RESOURCES AND ENVIRONMENT · TECHNICAL NOTE F.1 TABLE 6. ADVANTAGES/DISADVANTAGES OF DIFFERENT PRICE STRUCTURES Criterion One-time Fixed Variable Rates payment fee fee Constant Increasing Decreasing Revenue stability ++ + ­ ­ ­ Equity ­ ­ ­ ++ ­ ­ Efficiency (marginal cost pricing) ­ ­ ­ ­ + ++ ++ ++ Efficiency (incentives) ++ ­ ­ Administrative feasibility ++ ++ + ­ ­ ­ Administrative efficiency + ++ + ­ ­ ­ ­ ­ Note: +, ++, ­, ­ ­ means positively affected, strongly positively affected, negatively affected, and strongly negatively affected. Revenue stability: Revenues should not be too dependent on variable demand. Equity: Every person should have access to sufficient affordable water for survival. This applies within existing generations and between existing and future generations. Efficiency (marginal cost pricing): The price structure should be such that it provides incentives to efficiently use water (which requires that the price should reflect marginal economic costs). Efficiency (incentives): Prices should provide optimal incentive to engage in development of the water system and investment in water-saving technologies. Administrative feasibility: The most theoretically desirable pricing structures, such as marginal cost pricing, may be administratively difficult. For example, the administrative costs of installing sophisticated water meters may outweigh the gains. Administrative efficiency: Complex tariff systems may in practice be undesirable since they are expensive and may lack transparency. Source: Dalhuisen, J.M., H. L. F. de Groot, and P. Nijkamp. 2000. "The Economics of Water: a Survey of Issues," International Journal of Development Planning Literature, 15 (1): 3-20. If charging systems could be designed to even out practice, although some OECD countries have demand patterns and reduce peak demand, then commenced trials. There is insufficient evidence suppliers could reduce the capacity of their sys- from these trials at present to report on their ef- tems and so save capital and operations costs as fectiveness. well as reduce demands on the watershed. Peak- hour, peak-day, peak-week, and peak-month de- Rebates and incentives. Utilities can offer rebates and mands have all been investigated, as well as other incentives in order to accelerate the replace- differential prices in dry years and over longer dry ment of older, less efficient fixtures. These programs periods. Equity, technical feasibility, consumer can be targeted at the nonresidential and residen- understanding and acceptability, and risk all need tial sectors, and to indoor and outdoor uses, depend- to be considered before these temporal tariff struc- ing on where the greatest savings are likely to be tures are implemented. In practice, few attempts made. Various options include providing fixtures have been made to put these tariff structures into at no cost, offering a rebate for consumer-purchased BOX 9. INCREASED WATER TARIFF IN BOGOR, INDONESIA In 1988, average increases in water tariffs of about 115 percent for domestic users and about 170 percent for nondomestic users were instituted in Bogor in central Java. The monthly consumption of water per household dropped from an average of about 38 m3 to about 27 m3 per month. This price increase was accompanied by an intensive public education program. Since then, consumption has been maintained below previous levels, even though real water prices subsequently declined as incomes continued to increase until mid-1997. Source: IWACO-WASECO. 1989. 20 WATER CONSERVATION: URBAN UTILITIES fixtures, or arranging with suppliers to provide fix- Box 10 lists some common information and educa- tures at a reduced price. tion activities. The feasibility and effectiveness of replacements Water use regulations and standards. Regulations can may depend on state and local plumbing codes. be used to manage water during droughts or other Experience shows that such programs can yield water-supply emergencies. Typical restrictions in substantial water savings. developed countries include bans on nonessential uses (lawn watering, car washing, irrigating golf Information and education. Information and edu- courses, etc); restrictions on commercial car washes, cation are critical to the success of any conserva- nurseries, hotels, and restaurants; standards for wa- tion program, although their role in any savings may ter-using fixtures and appliances; and bans or re- be difficult to estimate. Customers that are informed strictions on once-through cooling. In some cases, and involved are more likely to support water con- utilities may find it desirable to extend water-use servation planning goals. Information and educa- regulations to promote conservation during non- tion measures can directly produce water savings emergency situations. Not all of these are relevant in by persuading consumers to use less water, as well developing countries, where restrictions such as lim- as support other conservation measures. For ex- iting access time to urban water are more common. ample, it is widely believed that information plays a role in how water consumers respond to changes Another type of regulation is to impose standards in price. on new developments with regard to landscaping, BOX 10. EXAMPLES OF INFORMATION AND EDUCATION ACTIVITIES FOR WATER CONSERVATION Information dissemination. Water utilities can provide information pamphlets to customers on request. Consumers are often willing to participate in sound water management practices if provided with accurate information. An information and education program could inform water users about the costs involved in supplying drinking water and demon- strate how water conservation practices will provide water users with long-term savings. Understanding the water bill. Customers can be helped to read and understand their water bills. Assuming that metering is installed, a water bill identifies volume of usage, rates, and charges. Comparisons to previous bills and tips on water conservation can help consumers make informed choices about water use. School programs. Utilities can provide information on water conservation practices through a variety of school pro- grams. These programs help educate young people about water conservation techniques, as well as help utilities communicate with parents. Public education program. Utilities can use a variety of methods to disseminate information and educate the public on water conservation. Outreach methods include speakers' bureaus, booths at public events, printed and video materials, and coordination with civic organizations. Workshops. Utilities can hold workshops for professions connected with water supply. These might include, for example, workshops for plumbers, plumbing fixture suppliers and builders, or for landscape and irrigation service providers. Promotion of new technologies. Utilities can also become involved with promoting new technologies through manu- facturers and distributors of fixtures and appliances. Demonstrations and pilot programs, and even contests, could be used to introduce and promote new products. Advisory committee. A water conservation advisory committee is another way to involve the public in the conservation process; potential committee members include elected officials, local business people, interested citizens, agency representatives, and representatives of concerned local groups. The committee would provide feedback to the utility concerning its conservation plan, develop new material and ideas about public information, and support conservation in the community. In order for such a step to be useful, the utility must be receptive to ideas offered by the committee. 21 WATER RESOURCES ANDENVIRONMENT · TECHNICAL NOTE F.1 drainage, and irrigation practices. Many water sys- I Large landscape audits. Audits for urban irri- tems, including privately owned systems, lack au- gation activities can provide the operators of thority to implement this measure. Utilities that have these facilities with information on water us- such authority must exercise it carefully. In general, age and usage-reduction techniques. These au- restrictions on water use should be justified by the dits can be used in conjunction with irrigation system's circumstances and should not unduly com- sub-metering and other landscaping efficiency promise the customer's rights or quality of service. practices. I Selective end-use audits. Audits can be widened Water-use audits. Water-use or end-use audits pro- to include selective end-use audits by customer vide water utilities and their customers with invalu- class, focusing on typical water-use practices able information about how water is used and how within each class. Audits targeted to older hous- usage might be reduced through specific conser- ing, for example, are particularly beneficial vation strategies. Water-use audits can be conducted in terms of identifying and fixing plumbing for different users: leaks. I Large volume users (both commercial and in- dustrial). Audits normally start with identify- All water audits should include a written report ing the categories of water use, and then containing specific ideas for conservation. Water identifying categories where water-use effi- audits may be planned and implemented in con- ciency can be improved through alternative junction with electric power companies or others technologies or practice (see also Box 2). interested in promoting conservation practices. ASSESSING WATER DEMAND AND CONSERVATION OPPORTUNITIES Successful projects are more likely to occur when I educating customers about the value of water water demand and conservation opportunities are I improving reliability and margins of safe and assessed early in the project cycle--during identifi- dependable yield cation, preparation, and appraisal. The U.S. Envi- I protecting and preserving environmental re- ronmental Protection Agency6 suggests nine basic sources. planning steps that apply generically to water con- servation planning. The process of developing and evaluating goals in- volves affected stakeholders as well as managers. Step 1: Specify conservation planning goals. Water An open process is particularly necessary with conservation planning goals may include: water conservation planning because many of the I eliminating,downsizing,orpostponingtheneed end-user measures--such as pricing reform or in- for capital projects stallation of low flow device--are not likely to be I improving the utilization and extending the life accepted by the community unless they understand of existing facilities the reasons for the interventions and fully support I lowering variable operating costs them. I avoidingnew-sourcedevelopmentcosts(seeBox 11) Step 2: Develop a water system profile. The water I improvingdroughtoremergencypreparedness system profile consists of system characteristics-- service population, service area, annual water sup- ply, service connections, water demand, water sales, 6USEPA (1998). average and peak demand, and pricing--and sys- 22 WATER CONSERVATION: URBAN UTILITIES BOX 11. WATER CONSERVATION AND INVESTMENT PLANNING IN AUSTRALIA Melbourne, Australia used a combination of water conser- 900 vation measures--such as water pricing reforms, water- 800 saving devices, and public education--to defer investment 1981 Trend of $25 million in infrastructure. As a result of the measures, 700 Melbourne's current water demand projection differs 600 substantially from the 1981 trend. The shift to the right of the (,000) 500 water trend curve has delayed the need to invest in additional supplies by about 6 years. 400 1990 Trend Megaliter 300 200 100 0 1977 1980 1983 1986 1989 1992 1995 1998 2001 2004 2007 2010 2013 2016 2019 2022 2025 Source: Bhatia, R., R. Cestti, and J. Winpenny, 1995. tem condition--critical water supply area, shortages It can also be used to compare conservation mea- or supply emergencies, unaccounted for water, sures with the supply-side options. A cost-benefit population and/or demand growth, and planning analysis can be used to determine whether the ben- of improvements or additions. efits of implementing a measure outweigh the costs. Step 3: Prepare a demand forecast. Forecasts can be Step 7: Select conservation measures. Cost-effective- made for the water system as a whole; however, ness is one criterion for selecting conservation forecasts are more accurate when they are prepared measures, but other factors such as ease of imple- for separate groups of water users. Demand-side mentation, staff resources and capability, environ- conservation measures should not be included. mental impacts, rate-payer impacts, environmental and social justice, water rights and permits, legal Step 4: Describe planned facilities. Preparing an es- issues or constraints, regulatory approvals, public timate of the costs of meeting the water demand acceptance, and consistency with other programs from improvements in supply without any conser- should also be considered. vation measures establishes the anticipated cost of supply-side improvements and additions. This cost Step 8: Integrate resources and modify forecasts. The estimate provides a benchmark for assessing con- demand and supply forecasts made in steps 3 and 4 servation or demand-side activities. should be revised in light of the anticipated con- servation savings. Step 5: Identify water conservation measures. Dur- ing this step, water utilities can identify the conser- Step 9: Present implementation and evaluation strat- vation measures that are relevant for their area. egy. The plan should be kept open to modification as implementation progresses. The implementation Step 6: Analyze benefits and costs. A cost-effective- strategy would normally include a preliminary ness analysis compares alternative conservation schedule for monitoring and evaluating program measures in terms of dollars per liter of water saved. results. 23 WATER RESOURCESAND ENVIRONMENT · TECHNICAL NOTE F.1 HERMANUS--A SOUTH AFRICAN CASE STUDY The town of Hermanus in South Africa provides an PRICING REFORMS instructive example of water demand management.7 Greater Hermanus consists of 11,500 properties The old water tariffs in Greater Hermanus were spread along a 25-kilometer stretch of coastline perverse, providing an increasing subsidy as more between the Bot River lagoon and the Klein River water was used. Under the new tariff structure, an estuary. This is a winter rainfall area. The town is a "assurance of supply charge" was instituted to de- popular seaside resort, world famous for whale liver the message that a tariff was needed to cover watching. The estimated permanent population of the fixed costs arising from having a supply of wa- about 20,000 increases threefold during peak holi- ter on tap. This charge was levied as a three-tiered day seasons. Water consumption during these peaks tariff because of South Africa's great disparity be- is very high. The water problem arises because the tween rich and poor. The rate of R40.00 per month sharp summer peak demand is out of synchroniza- was levied for the period 1996­97 for the typical tion with the rainfall peak. consumer (called economic tariff). The charge of R2.00 per month was levied for those in dire finan- Water supply for Hermanus is derived from the De cial situations (called the indigent tariff), while an Bos Dam, from which the local authority has an intermediate rate of R10.00 per month was charged annual allocation of 2.8 million cubic meters. At the for sub-economic households. time of construction in 1976, it was estimated that this allocation would be sufficient until the year An 11-point escalating block-rate tariff was devel- 2010. However, a property boom during the 1990s oped, based on the principle that those who tend to meant that during 1994­95 the water allocation was drive the marginal cost of water upwards should exceeded at a time when only some of the demar- be charged at the marginal rate (Table 7). While cated plots had been developed. A new analysis of the assurance-of-supply tariff depended on the in- the problem indicated that demand in a dry year come level of the household, the block tariff did not. could be as high as 4.9 million cubic meters. A hy- However, in keeping with the overall national goal drological analysis showed that the yield from the of using the water sector to promote social stabil- De Bos Dam could not be increased significantly, ity, the lower end of the tariff scale (the life-line thereby eliminating that supply-side solution. The cost of treating and distribution of groundwater made that source infeasible. Similarly, desalination TABLE 7. was discarded as a supply-side solution due to the THE NEW WATER TARIFF IN HERMANUS, SOUTH AFRICA. high energy costs involved. Kiloliter range Cost (R) per kl Total cost* Consequently, a demand management strategy was 0­5 0.30 0.00­1.50 6­10 0.70 1.50­5.00 adopted as the best solution to the problem. After a 11­15 1.20 5.00­11.00 series of intensive consultations between the local 16­20 1.80 11.00­20.00 authority and the South African Department of Water 21­25 2.40 20.00­32.00 26­30 3.00 32.00­47.00 Affairs and Forestry, a 12-point plan, the Greater 31­40 4.00 47.00­87.00 Hermanus Water Conservation Programme, was 41­60 5.00 87.00­187.00 developed. The plan included reforms of the pric- 61­80 6.00 187.00­307.00 ing system, technical improvements to reduce wa- 81­100 7.50 307.00­457.00 101+ 10.00 457.00­ ter use, education programs, provision of better information, and policy changes. Source: Brochure, Greater Hermanus Water Conservation Project, Department of Water Affairs and Forestry, 1998. *Note: (Add R2.00, R10.00, R40.00 assurance-of-supply charge 7Adapted from Turton, A.R. (1999). for indigent, sub-economic and economic users respectively.) 24 WATER CONSERVATION: URBAN UTILITIES tariff) was set to be affordable to all consumers. As ing of where the water is used within the house- part of the reforms, the local authority became more hold. The program has focused on educating chil- vigilant in dealing with those consumers who did dren, rather than adults, to promote a long-term not pay for water--a widspread practice in South change in attitudes. Every school child in the Greater Africa at the time, originally justified as a contribu- Hermanus area participates in a water audit at their tion to antiapartheid activities. Water was cut off to school. those consumers who had not paid their rates within seven days. This strategy is based on two distinct phases. The first phase focuses on the school environment. The TECHNICAL IMPROVEMENTS children are encouraged to monitor the schools' water meters over time. Once they have obtained a Given that 50 percent of total demand was from reasonable understanding of water usage, the chil- in-house use, the Greater Hermanus Water Con- dren are encouraged to investigate ways in which servation Programme planned to retrofit all homes the overall consumption levels can be reduced. This and other buildings that had piped water with is also linked to energy and waste disposal. The modern, water-efficient devices at no direct cost to second phase then involves the children applying the consumer. The retrofitting policy included the this newly learned skill to their home environments. following: This expands the auditing approach into virtually I assisting residents to check their meter for ac- every home in the area. curacy I assisting residents to monitor and repair water A Water-Wise Gardening project has been devel- leaks oped in conjunction with the local nursery indus- I assisting consumers to perform water-audits, try. This project is focused on planting indigenous from which conservation strategies could be vegetation, which tends to be more water-efficient, derived coupled with overall improvements in irrigation I encouraging consumers to have the safety and techniques. efficiency of their hot-water geysers checked I retrofittingwater-savingdeviceswherepossible Many of the local residents have limited financial and desirable by the owners. means. For this reason the potential use of grey- water for water-wise food production has been in- Retrofitting hardware included the installation of tegrated into the overall water demand management dual-flush toilet mechanisms, low-flow shower strategy. This involves some simple hardware modi- heads, and tap aerators. One invention consisted of fications, which are made possible through the ret- a wash basin built into the toilet cistern lid. This rofit program. recycled the water used to wash hands directly to the toilet cistern. BETTER INFORMATION This component of the program has been contro- Accurate metering is essential if the block tariff sys- versial because it only targets middle- and high- tem is to be successful. An innovative, pre-payment income homes (most low-income homes rely on water and electricity meter has been introduced to communal water facilities). Low-income house- help change the prevailing attitude of nonpayment holds felt that they were being left out. for services. The meter is linked to a central con- sole. It provides a high level of control by the con- EDUCATION PROGRAMS sumer, providing crucial information on how much water and electricity the consumer has used, how An important issue in water demand management much credit they have left, and how their level of is to ensure that the people have a good understand- consumption compares to the overall pattern in their 25 WATER RESOURCES ANDENVIRONMENT · TECHNICAL NOTE F.1 area. It can also warn of a leak and disseminate HERMANUS WORKING other information as needed. The new technology FOR WATER PROJECT even provides for a panic button, which is linked to a volunteer community group (ambulance, fire, or Although part of supply augmentation rather than police). demand side management, Hermanus has joined in the national Working for Water Project to remove One of the most successful aspects of the overall high-water-using alien vegetation in the catchment water demand management strategy has been the of the De Bos Dam. By clearing these plants, it is introduction of informative billing. This is based on hoped there will be increased runoff, which will the assumption that people are willing to cooper- substantially improve the yield of the dam, while ate if they get regular feedback about the impact of stabilizing the overall ecological functioning of the their actions. The monthly statement shows the level Onrus Lagoon and other local aquatic ecosystems. of consumption over the past year, how their indi- This element of the program complements the de- vidual consumption pattern compares with the av- mand reduction actions by increasing supply dur- erage for their area each month, and a measure of ing the dry season when demand levels peak. the influence of rainfall on consumption. EFFECTIVENESS OF THE PROGRAM Underlying the water demand management strat- egy is a strong commitment to communication be- tween the local authority and the consumer. This The Greater Hermanus Water Conservation uses instruments such as press releases, talks with Programme has achieved many of its goals. In the residents, displays, signs, newsletters, a hotline fa- short term, attitudes to water consumption have cility, and passing on information to other local changed through the provision of information that authorities. lets consumers make decisions that save them money. There was an 11 percent fall in annual av- POLICY CHANGES erage consumption in the two years after the pro- gram was implemented (Table 8). The increase in water use in September and October 1997 and 1998 Strong political institutions are needed to back up is possibly due to seasonal differences between the urban water conservation measures. In the post- base year of 1996 and later years. However, it is too apartheid period, South Africa introduced a plethora soon to know whether these reductions will be of new legislation based on a strong constitution maintained in the longer run. and bill of rights. Hermanus has chosen to adopt the National Water Regulations as a bylaw, thereby In addition, nonpayment for water has been signifi- ensuring that the rights and responsibilities of the cantly reduced. This has resulted in a budget sur- local authority and residents are given the full force plus for the local council. The surplus has been of law. Some of the consequences of this are: redirected to fund the retrofit scheme, which con- I the local authority performs an audit of its own sequently has been completed sooner than planned. performance in water management Nevertheless, the stricter enforcement of water I abanonwateringgardensbetween11a.m.and charges has been controversial. Some low-income 3 p.m., when there is a peak in water lost to families have found that even the relatively low block evaporation tariffs for minimal water use are too expensive; oth- I a ban on washing down paved surfaces with ers object to paying for water, which they regard as water a right under the new South African Water Law. To I strict guidelines on the energy and water-use this extent, the new tariffs have exacerbated the design parameters for new houses and devel- social and economic gap between the high- and low- opments. income groups. 26 WATER CONSERVATION: URBAN UTILITIES TABLE 8. PERCENTAGE CHANGE IN WATER CONSUMPTION , HERMANUS, USINGNOV 1995-OCT 1996 AS BASE YEAR Period 1993 1994 1995 1996 1997 1998 January -- 16 18 0 ­10 ­2 February -- 1 1 0 ­23 ­16 March -- ­4 5 0 ­15 ­15 April -- 0 ­20 0 ­18 ­19 May -- ­22 ­18 0 ­27 ­23 June -- ­32 ­15 0 ­15 ­15 July -- ­3 4 0 ­11 ­7 August -- ­23 15 0 ­7 ­1 September -- 1 17 0 2 7 October -- 31 2 0 23 18 November 17 ­1 0 ­35 ­23 -- December 5 21 0 ­14 ­16 -- CONCLUSION Worldwide, municipal water supply for industrial example, pricing reform will only be successful if and household use is the second largest water-us- educational activities bring consumers into the pro- ing sector after agriculture. Given urban growth gram and water saving technologies are made avail- rates in the developing world, this sector will ex- able to offset increasing unit prices for water. Such perience rapidly increasing demand over the next programs have had considerable success in reduc- 20 years. In developing countries, typically 30 to ing municipal water consumption in both the de- 50 percent of this water is currently lost through veloped and developing world, as shown in the cases leaks in distribution systems. Given the increas- of Melbourne, Australia, and Hermanus, South ing financial and environmental costs of tapping Africa. new sources of water supply, it is often economi- cally sensible to reduce the extent of leakage and Conservation measures are typically adopted thereby avoid these high development costs. In the through water utility reforms. However, if they are case of Singapore, where new sources are only adopted in isolation from broader water sector re- available at very high cost, it was economically ef- forms, then opportunities for achieving overall ef- ficient to bring levels of unaccounted water down ficiency gains are unlikely to be fully realized. Faced to just 6 percent. with increasing municipal water demand, the most cost-effective and most equitable solution can only It is also possible to reduce urban water demand be decided within the framework of integrated wa- through technological improvements, policy ter resources management. Typically, municipal changes including pricing reforms, and educational water conservation measures will be coupled with programs. These various elements normally sup- reductions in agricultural water demand and im- port one another, and so are packaged into inte- provements in water supply, together with institu- grated demand management programs. For tional reforms and water quality improvements. 27 WATER RESOURCES AND ENVIRONMENT · TECHNICAL NOTE F.1 FURTHER INFORMATION The following references provide general informa- IWACO-WASECO. 1989. Bogor Water Supply Project: The tion on water conservation, including planning for Impact of the Price Increase in June 1988 on the Demand for Water in Bogor. Rotterdam, NL: Royal conservation Haskoning. Gleick, P.H. 1998. "The changing water paradigm." The Bhatia, R., R. Cestti, and J. Winpenny. 1995. Water Con- World's Water 1998­1999: The Biennial Report on servation and Reallocation: Best Practice Cases Freshwater Resources. Pacific Institutes for Stud- in Improving Economic Efficiency and Environ- ies in Development, Environment and Security, mental Quality. A World Bank-ODI Joint Study. Oakland CA. Washington: Island Press. Washington: World Bank. U. S. Environmental Protection Agency. 1998. Water Conser- Turton, A.R. 1999. Water Demand Management (WDM): vation Plan Guidelines. Washington: USEPA. A Case Study from South Africa. MEWREW Oc- casional Paper No. 4, School of Oriental and World Bank. 1993. Balancing Water Demands with Sup- African Studies. London: University of London. plies, The Role of Management in a World of In- creasing Scarcity. World Bank Technical Paper Massachusetts Water Resources Authority (MWRA). 1994. Number 189. Washington: The World Bank. Water Use Efficiency Case Study: MicroSemi USPD Inc., Watertown, MA World Bank. 1996. Indicators--Water and Wastewater Utili- ties. Washington: World Bank. Some useful websites for particular techniques and experiences are: Guillermo, Y. 1995. Reduction of unaccounted for water, the job can be done. Washington: The World Bank. Welcome to WaterWiser http://www.waterwiser.org/ Financing urban water supply activities is discussed in: Cleaner Water Through Conservation http://www.epa.gov/OW/you/intro.html Asian Development Bank. 1999. Handbook for the Eco- nomic Analysis of Water Supply Project. Manila: American Water Works Association (contains links to Asian Development Bank. further U.S. sites with water conservation infor- mation) Serageldin, I. 1994. Water Supply, Sanitation and Envi- http://www.awwa.org/community/links.cfm ronmental Sustainability: The Financing Chal- lenge. Washington: The World Bank. International Water and Sanitation Centre http://www.irc.nl/ Various case studies are described in: 28