26322 Water Resources and Environment Technical Note E.2 Irrigation and Drainage: Rehabilitation Series Editors Richard Davis Rafik Hirji WATER RESOURCES AND ENVIRONMENT TECHNICAL NOTE E.2 Irrigation and Drainage: Rehabilitation 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 9 Sustainable Irrigation and Drainage Systems 10 Rehabilitation of irrigation and drainage systems should aim to correct the causes, not just the symptoms, that lead to degraded system performance or environmen- Author tal problems. Gary Wolff Strategic Environmental Issues for Technical Adviser Stephen Lintner I&D Rehabilitation 14 Environmental assessment of I&D projects, including Editor rehabilitation projects, must address numerous poten- Robert Livernash tial impacts. Production Staff Lessons from Experience 17 Cover Design: Cathe Fadel Strategic environmental assessments should consider project impacts at the basin scale; address drainage Design and Production: issues thoroughly from the outset; ensure the partici- The Word Express, Inc. pation of stakeholders; engage the private sector where possible; institute payment systems that ensure Notes adequate revenue; and create system performance Unless otherwise stated, and impact monitoring and feedback loops. all dollars = U.S. dollars. All tons are metric tons. Undertaking Rehabilitation and Modernization 21 Inadequate maintenance of irrigation and drainage Cover photo by projects is generally a result of either low government Curt Carnemark, World Bank budgetary allocations or insufficient fees collected from Rice paddy fields, Indonesia farmers. Institutional reforms almost always have to accompany technical improvements if rehabilitation This series also is available on the is to be successful. World Bank website (www.worldbank.org). Further Information 24 3 WATER RESOURCESANDENVIRONMENT · TECHNICAL NOTE E.2 Boxes 1. The Murray-Darling Basin Salinity Audit 18 2. Salinity reversal: The experience in Egypt and Pakistan 19 3. Performance improvements from participatory irrigation management 19 4. Cost sharing for I&D improvements in the Imperial Valley, California 21 5. Definitions: maintenance, rehabilitation, and modernization 22 Tables 1. Some environmental impacts specific to rehabilitation projects 14 4 IRRIGATIONANDDRAINAGE REHABILITATION 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 con- Water resources management is also a critical de- siderations. 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, pol- ture, often also contributing to loss of biodiversity. lution control, watershed management, control of In response, new policy and institutional reforms water weeds, and restoration of degraded ecosys- are being developed to ensure responsible and sus- tems such as lakes and wetlands--is an important tainable practices are put in place, and new predic- element of our lending, supporting one of the es- tive and forecasting techniques are being developed sential building blocks for sustaining livelihoods and that can help to reduce the impacts and manage for social and economic development in general. the consequences of such events. The Environment Prior to 1993, environmental considerations of such and Water Resources Sector Strategies make it clear investments were addressed reactively and prima- that water must be treated as a resource that spans rily through the Bank's safeguard policies. The 1993 multiple uses in a river basin, particularly to main- Water Resources Management Policy Paper broad- tain sufficient flows of sufficient quality at the ap- ened the development focus to include the protec- propriate times to offset upstream abstraction and tion and management of water resources in an pollution and sustain the downstream social, eco- environmentally sustainable, socially acceptable, logical, and hydrological functions of watersheds and economically efficient manner as an emerging and wetlands. 5 WATER RESOURCESAND ENVIRONMENT · TECHNICAL NOTE E.2 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 bilat- Bank implements its environment and water re- eral, multilateral, and nongovernmental organiza- sources sector strategies and supports the next gen- tions; and public and private sector specialists eration of water resources and environmental policy interested in environmentally sustainable water and institutional reforms. resources management. These people may have been trained as environmental, municipal, water resources, irrigation, power, or mining engineers; or as economists, lawyers, sociologists, natural re- Kristalina Georgieva sources specialists, urban planners, environmen- Director tal planners, or ecologists. Environment Department 6 IRRIGATIONANDDRAINAGE REHABILITATION ACKNOWLEDGMENTS The Bank is deeply grateful to the Government of ronment and Security. Additional sections were pro- the Netherlands for financing the production of this vided by Walter Ochs and Hervé Plusquellec. It was Technical Note. reviewed by Safwat Abdel-Dayem and Doug Olson of the World Bank. Ashok Subramanian of the World Technical Note E.2 was drafted by Gary Wolff of the Bank provided helpful comments Pacific Institute for Studies in Development, Envi- 7 IRRIGATION AND DRAINAGE REHABILITATION INTRODUCTION Irrigated agriculture provides about 40 percent of The World Bank's recently published Rural Devel- the world's food resources from 18 percent of the opment Strategy notes that future investment pri- world's cultivated land. A recent analysis1 shows orities for agricultural water use will focus on that 4,000 km3 of the 9,000 km3 of readily available improving the productivity of existing systems. This freshwater runoff is already used for human con- will not only defer the need for investment in new sumption. Compared to other water uses, irriga- sources of water, but will also help protect natural tion is a high volume, low quality, low cost use resources and the environment by maintaining accounting globally for 70 percent of the world's natural stream flows. The Strategy also points out water usage. Given this existing pressure on the that irrigation and drainage development and im- world's water resources, it is unlikely that many provements will need to be planned and executed major new sources of water will be developed for as part of integrated watershed/catchment systems. irrigation use. This Technical Note is one of three dealing with Most of the world's major irrigation districts were irrigation and drainage (I&D) issues. Technical Note developed more than 30 years ago. Many are now E.1 focuses on environmental aspects of irrigation in need of rehabilitation because of either failing and drainage development. Technical Note F.2 dis- infrastructure, excessive leakiness, or poor man- cusses issues, concepts, techniques and methods of agement. Even small improvements in water us- water conservation in irrigation schemes. This Note age rates (more crop per drop) can result in focuses on irrigation and drainage rehabilitation is- significant water savings, which can be used for sues. It provides information on the planned and other purposes including the production of more actual performance of irrigation and drainage sys- food. Furthermore, their environmental perfor- tems and explains why rehabilitation is so often mance is often unacceptable by modern standards. needed. It briefly presents relevant environmental For example, waterlogging and salinization are com- issues and associated terminology. Finally, the Note mon on-farm problems, impediments to fish mi- presents guidelines for strategic environmental as- gration, agrochemical sessments of irrigation pollution, and loss of and drainage projects wetlands are common and drainage rehabili- off-farm problems. In tation projects. Central Asia, the reha- bilitation of failing ir- 1 "Water Resources rigation systems is 2000-2001. People and essential for the suste- Bank Ecosystem: The Fraying nance of the popula- orld W, Web of Life." Washing- tion. It will require a ton D.C.: UNDP, UNEP, massive investment be- World Bank, Water Re- Plusquellec yond the resources of vé sources Institute. any single institution. Her by Photo Long, crested weir regulator, Majalgaon, India 9 WATER RESOURCES AND ENVIRONMENT · TECHNICAL NOTE E.2 SUSTAINABLE IRRIGATION AND DRAINAGE SYSTEMS ACTUAL VS. EXPECTED ied considerably. Actual efficiencies varied from 48 PERFORMANCE to 92 percent of the design efficiency. Although both studies were based on samples, they Rehabilitation of irrigation and drainage systems typify the status of I&D systems in many parts of should aim to correct the causes, not just the symp- the world. The economic and environmental con- toms, that lead to degraded system performance or sequences of these inefficiencies affect many eco- environmental problems. Inefficient water use, for nomic sectors. For example, low water-use efficiency example, may reduce the number of hectares that causes either lost agricultural production (because can be irrigated or cause soils to become water- water is not available for agriculture elsewhere in logged. The causes of low water-use efficiency could the project area or because water-logging and sa- include an operation and maintenance budget that linity depresses yields) or problems with activities is inadequate or improper water pricing. such as fishing upstream or navigation downstream. Similarly, overuse of water causes excess leaching LESSONS FROM BANK EXPERIENCE of nutrients and chemicals, erosion of surface soils with attached fertilizers or pesticides, and reduc- In 1989, the Operations Evaluation Division (OED) tions in environmentally important flows. This in- of the World Bank reviewed 21 Bank projects that creases the cost of agricultural production, reduces were approved between 1961 and 1978 and com- the quality of water for human uses downstream, pleted between 1970 and 1986.2 The projects were and damages downstream aquatic habitats (see Note considered typical of those supported by the Bank C.1). in the 1960s and 70s. While all had yielded impor- tant long-term economic benefits, their general eco- In spite of I&D systems performing at less than their nomic performance was less than expected at the design expectations, a major 1995 OED study of 208 time of project completion. The generally lower than Bank-funded irrigation projects3 found that two expected cost recovery was attributable to the poor thirds had been rated satisfactory (84 percent sat- performance of the irrigation systems--both physi- isfactory if weighted by area). Over 16 million farm cal aspects and operational aspects. Thus, the physi- families benefited directly from these projects, and cal infrastructure had deteriorated markedly, partly many millions more benefited indirectly. because of poor construction and partly because of poor maintenance. The rigid operation of water de- The message from these reviews is that, although livery, often according to a fixed schedule, meant Bank investments in irrigation have successfully that farmers could not optimize their use of water benefited millions of people, there is a consider- and much water was wasted. Although the projects able need to rehabilitate old projects (including ones had environmental benefits, more than half also had not funded by the World Bank) because of poor con- negative environmental effects, including waterlog- struction, inadequate maintenance, poor operational ging and salinization, as a result of poor drainage. procedures, lack of adequate drainage, and institu- Most of the projects were unlikely to be viable in tional deficiencies. The need for rehabilitating de- the long-term without rehabilitation to both physi- cal infrastructure and changes to operational pro- cedures. 2OED, 1991. Annual review of project performance au- Similarly, a 1990 evaluation of water-use efficiency dit results. Operations Evaluation Department. Washing- in 10 internationally funded irrigation systems found ton DC: World Bank. that actual performance of irrigation schemes var- 3Jones, W. I. (1995). 10 IRRIGATIONANDDRAINAGE REHABILITATION teriorating I &D infrastructure and reforming in- Unrealistic or culturally unsuitable designs. Designs stitutions is probably most apparent in Central Asia, that entail operation and maintenance practices that where little has been spent on maintenance since are not within local capacity are numerous. Usu- the end of the Soviet era and where many commu- ally this fault can only be corrected realistically at nities are dependent on irrigated agriculture. All the design stage; task managers need to assess all Bank-funded investments in rehabilitation will be designs carefully for the realism of their operational carried out in accordance with the Bank's sector implications. In assessing the Maneungteung Irri- strategies and safeguard policies, so that the result- gation Project in Indonesia, a 1994 World Bank re- ing I&D schemes are environmentally and socially port5 observed that the "system calls for a bi-weekly sustainable in the long term. assessment of demand for every tertiary block, and a readjustment of every gate in the system to meet REASONS FOR UNDER-PERFORMING the changed water distribution plan. This requires IRRIGATION AND DRAINAGE a very intensive data collection program and an ef- ficient and effective information management sys- SYSTEMS tem. Because it is carried out in an environment of unpredictable water availability, it becomes almost The common performance and environmental impossible to achieve, even if there were a huge problems that have plagued large-scale irrigation increase in the number and skills of field staff." In and drainage systems are discussed in the docu- this case, an effective rehabilitation project would ments listed at the end of this Note. These prob- need to focus on re-design to make operational pro- lems typically have social and political aspects as cedures much simpler, rather than on increasing well as technical aspects, so managers need to local capacity to operate the system as it was ini- consider non-technical issues even when the tech- tially (and inappropriately) designed. nical issues are apparent. Another common problem is the inclusion of tech- Inappropriate policy objectives. Investments in I&D nologies--such as control gates in subsidiary distri- systems are made in the pursuit of social objectives. bution channels--where there is a lack of capacity For example, deliberate policies to build simple and to enforce proper operation of these devices. Con- cheap I&D systems as rapidly as possible have been sequently, such devices are widely misused to ben- adopted in the pursuit of food security or to sup- efit locally powerful irrigators. port migration (e.g. California). The OED study cited above included such inappropriate policy objectives Inadequate management capacity for operation and among the core reasons for underperformance of maintenance (O&M). In other instances, system many of the I&D systems it surveyed. design is realistic and appropriate for the country, but management capacity is inadequate to operate This problem is by no means limited to infrastruc- and maintain the system effectively. The term "in- ture investments in the developing world. A 1998 adequate management capacity" covers a very broad World Bank report4 noted that the "objectives of category of causes. Some of the more common ca- closer settlement in rural Australia had a great in- pacity issues, discussed in more detail in the docu- fluence on the development of irrigation. Unfortu- ments cited in the Further Information section, are: nately the lack of financial discipline inherent in s Insufficient training of O&M staff. This in- these policies left a legacy of irrigation enterprises cludes not just an understanding of how to op- of low profitability, small farms, financially unviable irrigation authorities, ageing irrigation infrastruc- ture, a large public debt, and environmental deg- 4 radation through salinity and waterlogging." Langford, K. J. , C.L. Forster, D.M.Malcolm (1998). 5Murray-Rust, D. H., and W.B. Snellen (1991), in a draft paper cited by Plusquellec et.al. (1994). 11 WATER RESOURCES AND ENVIRONMENT · TECHNICAL NOTE E.2 erate the system under a variety of conditions, but the importance of systematic preventative maintenance plans.6 Maintenance costs (includ- ing losses to users when the system is "down") are highest when maintenance is only per- formed after system components break down. s Insufficient training of accounting and finan- cial staff. It is difficult to operate more efficiently or avoid environmental problems based on past experience when staff members do not know how to analyze the information. s Inadequate accounting and financial prac- tices, even when staff members are well trained. For example, depreciation based on historical costs, although commonly used to account for capital consumption, does not pro- vide financial reserves to replace capital assets when they are worn out. In some cases, this depreciation practice, even if well implemented, will eventually undermine system operation. s Inappropriate pay and career pathways for employees. This includes not only inadequate pay or opportunities for advancement for jun- Bank ior staff, but also excessive pay and patronage orld or years-of-service systems of promotion for W, more senior staff. Poorly motivated staff have Ochs little incentive to collect fees and may be more alter W susceptible to corruption. The result is that many by water users do not pay for their water, reducing Photo the income that should be used for maintenance. Irrigation ditch and turnout, near Manisa, Turkey s Insufficient experience with new manage- ment strategies or tools. Although not always a cause of O&M failure, there is increasing de- stream water users to withhold payment for sys- mand for management staff to apply new tech- tem operation and maintenance, which can make niques when they have no background or water delivery even more erratic or infrequent. As training in these topics. Experience in developed a result, downstream users sometimes shift to un- countries shows that some of these management controlled groundwater abstraction, causing deple- skills cannot be taught but must be obtained tion of aquifers. through experience. Conflicting incentives can also occur between Conflicting incentives. Management rules or behav- project beneficiaries and other groups. For example, iors can create incentives that diminish system per- formance or create environmental problems. A common example occurs when water delivery is erratic. This creates an incentive for upstream wa- 6The 1989 OED study cited previously concluded that ter users to take as much water as they can, reduc- poor construction standards, insufficient funding, and lack ing or eliminating water for downstream water of systematic maintenance plans were the main reasons users. This, in turn, creates an incentive for down- for poor maintenance. 12 IRRIGATIONANDDRAINAGE REHABILITATION drainage systems that dispose of irrigation water in Priority given to irrigation over drainage. A politi- a way that damages downstream water quality (see cal emphasis on the development of irrigation sys- Note D.1) may create an incentive for irrigators to tems, with drainage issues being either neglected neglect maintenance of drains so that they discharge entirely or postponed, has in a number of cases less water as an informal way of responding to com- caused environmental damage and consequent re- plaints from downstream relatives or neighbors. If duction in agricultural performance. Neglect of ag- this happens, the irrigators will be rewarded socially ricultural drainage does not usually cause by fewer complaints, but they will be affected even- performance or environmental problems in the tually by reduced yields and increased waterlog- short term, but it is probably the most significant ging if they continue to irrigate without adequate cause of these problems in the long term. A World drainage. Thus, environmental problems can result Bank study9 examined 186 I&D projects from 1983 from conflicting incentives implicit in the system to 1991. Of these, 125 were irrigation alone, 16 were design and the O&M procedures. drainage alone, and 45 were both irrigation and drainage. Input subsidies or output controls. There is an ex- tensive literature on the environmental and opera- In particular, soil degradation from salinity has tional problems that have resulted from subsidized undermined the initial agricultural gains from ir- water pricing or from controls over production. rigation. Although the data are old (1985 to 1992), Water-use efficiency, for example, is much lower the above study reported that areas with irriga- in cases where recipients of irrigation water are tion-induced salinity, expressed as a percentage charged by size of the area irrigated rather than by of total irrigated area, amounted to 11 percent in the volume of water used because the land area is India, 21 percent in Pakistan, 10 percent in Mexico, fixed, and so there is no incentive to use less water. 23 percent in China, 48 percent in Turkmenistan, Waterlogging, excess use of fertilizer and pesticides, 24 percent in Uzbekistan, 17 percent in degraded water quality, aquatic habitat degradation Kazakhstan, and 28 percent in the United States. downstream, and other environmental and perfor- Studies in India, Mexico, and Turkey found yield mance problems have been documented to result losses of 30 to 56 percent due to irrigation-induced from these pricing practices. salinity, and associated reductions in net income to farmers of 35 to 97 percent. These figures do Pricing schemes that distort water use are wide- not apply to all cases of soil degradation, but they spread. A 1995 World Bank review7 found that area- show that the drainage component of irrigation based pricing exists in 9 of the 11 developing systems is closely linked to both environmental countries and 2 of the 5 developed countries stud- impact and economic performance. Irrigation sys- ied.8 The review also found that 15 of the 16 coun- tem rehabilitation projects must address all soil tries--including all five developed countries--do not or water degradation problems to make the over- have rates that fully recover the cost of providing all schemes sufficiently sustainable to avoid fu- irrigation water. ture rehabilitation. Subsidies for agricultural inputs have also contrib- uted to extensive water pollution and soil degrada- tion, most notably in the agricultural areas of the transition economies of the former Soviet Union. 7 Output controls, such as specification of crop type, Tsur, Y., and A. Dinar (1995). used in India and other countries to maintain self- 8Only volumetric rates are used in the other five coun- sufficiency in staples, will also contribute to envi- tries. Volumetric rates are combined with area-based rates ronmental and performance problems when in two of the nine developing countries and one of the irrigators have to forgo other crops that are better two developed countries with area-based rates. suited to local conditions and market prices. 9Umali, D. L., (1993). 13 WATER RESOURCES AND ENVIRONMENT · TECHNICAL NOTE E.2 STRATEGIC ENVIRONMENTAL ISSUES FOR I&D REHABILITATION Environmental assessments (EA) of I&D projects, tegic" will differ between projects. As emphasized including rehabilitation projects, must address nu- previously, identification of possible environmen- merous potential impacts. These are listed in the tal problems is not enough. The underlying causes World Bank's 1991 Environmental Assessment of these problems need to be identified and cor- Sourcebook and its updates. The documents in the rected. Further Information section provide more techni- cal information. Table 1 lists some additional im- ON-SITE AND OFF-SITE IMPACTS pacts that can arise with I&D rehabilitation projects. On-site impacts on irrigated or drained land include Some potential environmental impacts are strate- soil erosion and other damage to soils in irrigation gic. That is, if recognized early in the project cycle, areas; off-site impacts include downstream pollu- they can lead to alterations in the project plan or tion or deposits of eroded soil. The distinction is conceptual design. Thus, lining irrigation canals important because on-site impacts are borne by the when they are being rehabilitated may initially seem party that benefits from irrigation or drainage, while prohibitively expensive. However, if more drains will off-site impacts are borne by others, sometimes in- eventually be required to prevent waterlogging due cluding downstream beneficiaries of irrigation or to seepage, then a system design that includes lined drainage. In a perfect world, farmers would weigh canals may be economically and environmentally the cost of on-site impacts against the benefits of superior (see Note F.2). irrigation and drainage, and decide how much on- site damage to accept. However, farmers may adopt Depending on local circumstances and the history a short time horizon and may not possess full knowl- of the I&D facilities that are to be rehabilitated, the edge about these impacts, so their decisions may environmental and production issues that are "stra- not be optimal. Thus, strategic solutions to on-site TABLE 1. SOME ENVIRONMENTAL IMPACTS SPECIFIC TO REHABILITATION PROJECTS Potential Impact On- or Off-Site Possible Strategic Actions Leached elements from disposed, Off-site If testing confirms this possibility, seek to dredged sediments incorporate dredge spoils within engineering embankments or other less exposed locations. Loss of habitat within heavily silted or On-site Construct similar habitat outside the canals vegetated canals using dredged materials. Loss of habitat supported by leaking On- or off-site Assess the economic value of this habitat and, irrigation facilities if feasible, convince beneficiaries to pay for irrigation water or drainage flows to sustain the habitat. Reduced fish spawning or survival On- or off-site Install fish ladders or other facilities to support due to inability to pass formerly leaky fish migration, paid for by beneficiaries. control gates or structures Human health impacts from restoring Primarily off-site Perhaps allow continue informal use if flows from canals that are being (downstream) modeling indicates health risks are minimal. If (informally) used for sewage disposal risks are significant, include sewage disposal as part of the project. 14 IRRIGATIONAND DRAINAGE REHABILITATION impacts often involve education and technical as- from surface ponds or groundwater systems that sistance to farmers, so they have information on the are fed by these leakages. Rehabilitation may also long-term consequences of their decisions. eliminate habitat that was originally created by the I&D system itself, but is now scarce and valuable Off-site impacts, on the other hand, exemplify nega- because most natural habitat of that type has been tive10 environmental externalities. Inexpensive pol- destroyed. The Santa Clara Valley Water District in lutant disposal is beneficial to the creator of northern California, for example, is required to re- pollution, but harmful to the downstream recipi- move sediment and vegetation from one side only ents. Unless the polluter pays the recipients for the of flood control channels in order to maintain in- costs they face--or, under some circumstances, the channel habitat because rare species of birds may recipients pay the polluter to reduce pollution--the now be dependent on this habitat. This concern typi- optimal level of pollution will be exceeded. Strate- cally arises with rehabilitation of unlined I&D ca- gic solutions to off-site impacts often involve get- nals and I&D canals or control structures where ting the affected groups to agree on how to share adjacent wetlands have developed because of con- the benefits and costs of the new project, and to me- tinual leakage. diate the disputes that will inevitably arise as the remediated I&D system is constructed, operated, and More direct habitat loss can occur during rehabili- maintained. tation. Examples include wetlands that are drained for agriculture as a result of water-use improve- WATER QUANTITY AND QUALITY ments, land flooded by new or expanded reservoirs, and floodplains that are no longer flooded because they are protected by levees. Less obvious on-site The same water quantity and quality issues that are habitat loss may also be important. For example, a considered when an I&D project is being developed declining water table--caused by either reductions are also relevant when an existing scheme is being in recharge because of leakage control measures rehabilitated. Thus, the effect of changes in water or groundwater being used for supplementary irri- flow on both upstream and downstream commu- gation--may cause deep-rooted trees and shrubs to nities and environments should be assessed as part die. of an EA. These would include effects on livelihoods (fishing, recession agriculture, fiber, small-scale Development of new or improved drainage systems irrigation, etc) as well as effects on environmental as part of rehabilitation will almost always lead to processes, particularly those that communities de- beneficial on-site effects (see below) but may lead pend on. Changes in flow that trigger fish breed- to either beneficial or detrimental downstream ef- ing, alter habitat, or maintain wetlands and fects. For example, the rehabilitation can lead to an floodplains are examples of such environmental increase in the discharge of nutrients and pesticides processes. Generally, rehabilitation will lead to if modern irrigation techniques and improved crop greater water use efficiency, so there will be op- varieties are introduced. On the other hand, it can portunities to mitigate these adverse effects, includ- lead to a reduction in the discharge of these pollut- ing effects from when the I&D scheme was ants if on-farm water conservation techniques are constructed, using the "saved" water. I&D rehabilitation will commonly lead to reduced water losses from both canals and on-farm distri- 10Positive environmental externalities also occur, but less bution and application systems. These reductions frequently. For example, irrigation system rehabilitation can affect communities and habitat within the I&D can reduce the incidence of water-related diseases (e.g., area that have become dependent on this source of malaria transmitted by mosquitoes). For people outside water. Thus, it is common for villages that have de- the service area that is rehabilitated, a positive environ- veloped within the I&D area to obtain their water mental health externality exists. 15 WATER RESOURCES ANDENVIRONMENT · TECHNICAL NOTE E.2 introduced that reduce leaching and surface runoff vent excess deep percolation, thereby lowering the (see Note F.2). Again, rehabilitation can lead to watertables and conserving surface water supplies. longer growing seasons, greater abstractions of water during the dry season, reduced dry season Salinity buildup will reduce the yield of crops that river flows and detrimental impacts on downstream are sensitive to the particular salts that accumu- environments. Each rehabilitation project will have late. Changing to less sensitive crops will reduce to be assessed on its merits, and a decision made this problem, temporarily. An imbalance between that takes account of not just the benefits of the re- salt ions, most notably an excess of sodium in com- habilitation to the farmers in the I&D area but also parison with calcium and magnesium, can degrade the downstream benefits and costs. soil structure (see Note E.1). For example, clay par- ticles in soil may swell or form a crust when wet- SALINIZATION ted, reducing or preventing water infiltration, or they may clump, reducing air penetration and water Salinization is one of the most common and most holding capacity. costly environmental consequences of inadequate drainage in irrigation areas. It occurs either because OTHER SOIL DEGRADATION ISSUES irrigation water contains dissolved solids (many of which are salts) and evaporation from fields leaves Acidification refers to the process of increasing soil behind a salt burden, or because excessive applica- acidity, either due to irrigation with acidic water tions of water cause the watertable to rise, bringing or drainage of lands that contain high concentra- old salt deposits to the surface. If the surface soils tions of unoxidized organic matter. The first cause already contain a high salt concentration from one is not common, and can be avoided through moni- of these causes, then a small excess of irrigation toring of irrigation water quality, lime addition, or water (the leaching fraction) needs to be applied to other means of buffering soil against excess acid- gradually wash the salt to either deeper groundwa- ity. The second cause is more widespread and more ter or to drainage systems (where it may cause other serious. Swamps and mangrove forests often environmental problems). If the salt is brought to accumulate unoxidized organic matter as stagnant the surface by rising groundwater tables, then irri- or brackish water is depleted of oxygen by decom- gation water needs to be applied carefully to pre- position of organic matter. Drainage can expose organic matter, which then oxi- dizes, releasing more organic acids that are in turn degraded by bacteria. Acid-sulphate soils are an extreme example of a drainage-induced acidification problem (see Note E.1) , where the pH can drop to 3. Waterlogging occurs when Bank near-surface soils become satu- orld rated due to either a rise in the W, water table or water becoming trapped near the surface due to Plusquellec an impermeable sub-soil layer. vé Her Waterlogging can cause fields by and nearby lands to flood eas- Photoily. It makes access to fields Salinized soils, China 16 IRRIGATIONANDDRAINAGE REHABILITATION (other than rice paddy) more difficult, and prevents depleting the topsoil. Less topsoil may not be a prob- air from penetrating soil pore spaces. Lack of air in lem initially, but can eventually make rooting diffi- soil leads in turn to the death of many species of cult for plants and make them more susceptible to worms and other soil organisms that aerate the soil being uprooted by wind or water. Wind-borne ero- and make nutrients available to crop species. sion is less common, but can be quite severe if the soil structure has been degraded by other factors Soil erosion, borne either by wind or water, is rela- such as salinization. tively common, leading to nutrient loss as well as LESSONS FROM EXPERIENCE The following guidelines summarize lessons from resources planning that is being introduced in Tamil past successes and mistakes. They are not a blue- Nadu and Orissa, India, includes I&D system reha- print or checklist, but provide signposts towards bilitation and exemplifies this type of approach. This successful I&D rehabilitation. type of planning led to cancellation of the formerly proposed Gumti 2 Flood Control and Irrigation CONSIDER PROJECT IMPACTS project in India because the economic loss of (non- AT THE REGIONAL SCALE commercial) fish traditionally caught on the flood- plain was estimated to be greater than the flood control benefits of the project. This example shows The World Bank has endorsed integrated water re- how I&D system rehabilitation may be economi- sources management since its 1993 Water Resources cally justified on agricultural grounds alone, but Management Policy. Water and salt balance calcu- cannot be justified from a multisectoral, regional lations are a relatively simple way to introduce in- perspective. tegrated management issues into the comparison of conceptual alternatives for a rehabilitation project. ADDRESS DRAINAGE ISSUES This has been done successfully in the Indus Basin THOROUGHLY FROM THE OUTSET of Pakistan through a series of salt balances. In Australia's Murray-Darling Basin, a recently released salinity audit (Box 1) demonstrates how such analy- When drainage is left until a later stage of develop- sis can guide regional investments in salt reduction, ment, it is critical to have a firm commitment to par- so that project investments are part of a regional ticular drainage facilities from the outset. As the least-cost strategy to achieve environmental objec- selenium problem in the Kesterson ponds (see Note tives. That is, the amount of salt control required E.1) demonstrated, failure to realistically specify from each I&D rehabilitation project partially de- when, how, and at whose expense drainage facili- pends on the regional salt balance and partially on ties would be installed led to serious environmen- regional economic and environmental priorities. In tal problems. In most cases, failure to provide the case of the Murray-Darling Basin, this region- irrigation drainage will eventually lead to signifi- wide analysis has been followed up with rules for cant economic losses, so detailed planning and fi- water allocation and management that take account nancial guarantees should be sought for drainage of the needs of all water users. facilities early in I&D rehabilitation planning. Al- though irrigation systems that were initially con- Similarly, the targets for water-use efficiency de- structed without drainage can be rehabilitated in pend on alternative uses for water in the region, some cases (Box 2), experience has shown that such including instream uses both upstream and down- facilities tend to become political priorities only af- stream of the project site. Comprehensive water ter significant damage has occurred. 17 WATER RESOURCES AND ENVIRONMENT · TECHNICAL NOTE E.2 BOX 1. THE MURRAY-DARLING BASIN SALINITY AUDIT The irrigation and drainage management program of the Murray-Darling Basin in Australia is among the most advanced I&D management programs in the world. By the late 1980s, 96,000 hectares of irrigated land in the basin were showing visible signs of salinization, and it was estimated that areas affected by high water tables would increase from 560,000 hectares in 1985 to 870,000 hectares in 2015. Estimates of basin-wide impacts of salinity and water table rise range from $600 million to $1 billion per year over the coming century. These findings prompted development of a salinity and drainage strategy, including regional cooperation among five state governments, the Australian federal government, and many communities within the basin. The basin- wide strategy achieved impressive gains by the late 1990s. For example, at a key downstream monitoring location, salt concentrations exceeding the target level of 800 electrical conductivity units (ECU) declined from 42 percent to 8 percent of the time. Projections, however, suggested that salt concentrations will rise over the next 100 years, and these gains could be lost within perhaps 20 years. These projections were examined in much greater detail through an audit of all salt sources in the basin completed in late 1999. The audit produced numerous important findings, of which three were clearly relevant to setting priorities for environmental investments within the basin. First, salinity trends were more severe than previously anticipated. The annual movement of salt in the basin landscape was estimated to double in the next 100 years. Secondly, salinization of non-irrigated, dryland farming areas is significant (around 300,000 hectares in 1995), and salt from dryland farming areas is anticipated to contribute 60 percent of the salt load in the lower Murray River in future decades as irrigation loads are controlled. This has significant implications for the long-term benefits of continuing investments in I&D rehabilitation. Thirdly, significant salt loads are created from drainage of naturally occurring, saline groundwater that can often be prevented or reduced at relatively low cost. The salinity audit demonstrates the value and feasibility of basin-wide analysis of significant environmental problems. The limitation that the increasing salt load from dryland salinity imposed on further I&D rehabilitation had not been previously recognized, and this result significantly affected decisions at the I&D project level. Admittedly, it is difficult to integrate project planning with basin-wide planning, especially when data and financial resources are more limited than in Australia. But less-complicated evaluations of strategic consider- ations at the basin level are valuable for putting I&D investments into a larger context. Source: The Murray-Darling Basin Commission. 1999. The Salinity Audit of the Murray-Darling Basins. Canberra Australia: The Murray- Darling Basin Commission. ENSURE THE PARTICIPATION support, which increases performance over time. OF STAKEHOLDERS However, it is clear that improved collection of fees and charges only results in improved system per- formance if the irrigation system has financial in- Promoting the participation of water users in the dependence from government.11 Otherwise, the fees management of irrigation systems has greatly im- end up in consolidated government revenue and are proved the performance of I&D systems in many not used within the irrigation area. Because the cost countries, including Turkey, India, the Phillipines, of on-site environmental impacts is borne by water and Mexico. Examples of the types of performance users, PIM also has the potential to reduce on-site improvements that have been achieved by partici- environmental impacts such as waterlogging and patory irrigation management (PIM) are provided salinization. However, there is little evidence of this in Box 3. happening at present. One of PIM's objectives is to replace the vicious cycle Off-site environmental impacts are unlikely to be of low irrigation system performance--leading to low reduced by PIM, unless those who are harmed by farmer support and lower performance--with a greater sense of ownership, leading to improved system performance and greater participation and 11Jones, W. I. (1995). 18 IRRIGATIONANDDRAINAGE REHABILITATION BOX 2. SALINITY REVERSAL : THE EXPERIENCE IN EGYPT AND PAKISTAN In general, it is economically and environmentally better to prevent salinization through well-designed drain- age systems than to have to reverse it once it has occurred. However, it can be reversed in many cases, as experience in Egypt and Pakistan demonstrates. By 1970, about 60 percent of all cultivated land in Egypt was classified as moderately to severely affected by salinity and waterlogging, with crop yields below the national average. Only about 7 percent of irrigated land was unaffected by these problems. As a result, large-scale drainage works were introduced in the 1970s. By June 1990, some 1.43 million hectares had been provided with drainage systems (out of 2.95 million hectares of total arable land). The installation of the drainage systems reduced soil salinity and increased yields. After drainage was installed, soil salinity declined by a factor of 2 to 5 in newly drained areas, wheat yields increased from 1 to 2.4 metric tons per hectare, and maize yields increased from 2.4 to 3.6 metric tons per hectare. Pakistan irrigates about 14 million hectares of land--one of the largest irrigation systems in the world. Unlined irrigation canals, inefficient irrigation practices, and the absence of drainage have all contributed to extensive waterlogging and salinity problems. The Water and Power Development Authority initiated a program of salinity control and reclamation projects (SCARPs) in 1958. By the late 1980s, about 3.7 million hectares were serviced by SCARPs. Deep tubewells were used to assist drainage. In areas with saline groundwater, they promote deep drainage. In areas with fresh groundwater, they permit supplemental irrigation with groundwa- ter, lowering the water table and reducing the demand for irrigation from surface waters. Despite numerous obstacles and setbacks, an average of 80,000 hectares of affected lands have been brought back into production every year due to improved drainage. Source: Umali, D. L. (1993). BOX 3. PERFORMANCE IMPROVEMENTS FROM PARTICIPATORY IRRIGATION MANAGEMENT Involving irrigation water users and other stakeholders in management of I&D systems often greatly improves system performance. For example, irrigators in New Zealand were able to reduce costs by nearly 66 percent due to increased efficiency of operation, lower overhead costs than government management, reduction in overly elaborate engineer- ing design and specifications, and the greater personal responsibility irrigators take for maintaining the systems they themselves own. Similarly, in Chile, government management of 60,000 hectares of irrigated land on the Rio Dugullin involved 5 engineers, 8 to 10 technicians, 15 to 20 trucks, and 5 bulldozers, compared to 1 engineer, 2 technicians, 1 secretary, and 2 trucks under farmer management in the same area. Greater knowledge of user needs and responsibility for meeting (and paying for) one's needs create incentives for cost-effectiveness that often do not exist under other types of management. Increased performance, and the closer link between O&M expenditures and those who pay for them, was also reported to increase the willingness-to-pay of irrigation water users in this Chilean example. In Senegal, poor service reliability under agency management resulted in a low collection rate of irrigation fees. Electricity was subsidized and agency staff usually turned pumps on and left them on, resulting in overpumping and frequent system breakdowns. Farmers' fees increased by a factor of two to four when water users took over the system and paid for full electricity consumption, along with maintenance and a fund for pump replacement. Water users were willing to pay these higher fees because service reliability increased and was now largely within their control. Source: Subramanian, A. et al (1997). off-site impacts are included in the water user group. EA should assess whether significant off-site im- Participatory management by water users alone pacts exist now or might exist after rehabilitation, might greatly improve system performance and and whether those who are affected by these im- reduce on-site environmental impacts, while ignor- pacts can participate in irrigation management in ing or even increasing off-site impacts. A strategic a way that will encourage tradeoffs to occur between 19 WATER RESOURCES ANDENVIRONMENT · TECHNICAL NOTE E.2 those causing and those facing these impacts. Even greater income inequality may be failing to take though experience shows the benefits from the par- advantage of profitable opportunities recognized by ticipation of water user groups in water allocation their poorer citizens. and management, institutions such as government departments still need to be involved. They possess INSTITUTE PAYMENT SYSTEMS THAT legal authority and financial resources that are es- ENSURE ADEQUATE REVENUE sential for effective management. The worst environmental and production problems INCREASE THE ROLE OF are usually caused by inadequate revenue for op- THE PRIVATE SECTOR eration and maintenance, for completing the ini- tial system design (e.g., drainage components), or Many irrigation systems include privately owned for replacing capital facilities as they decay. Rev- components. For example, Egyptian irrigation ca- enue and financial issues have an important stra- nals are usually lower than the fields that are irri- tegic environmental dimension, which is usually gated. Each farmer or group of farmers owns the too late to address at the EA stage of the project pumps that lift water from canal to field. Although cycle. there is a trend toward privatization of the public portion of irrigation systems, there has been less Revenue is limited by the willingness of those who (but nonetheless substantial) attention to involving benefit from the I&D system to pay for services. Ir- the private sector in investments that complement rigation water has often been subsidized because operation of the public system. of the perceived benefit to the nation from agricul- tural development. As that perception has changed, In Bangladesh, institutional changes that made it political support for these subsidies has declined. possible for farmers to purchase and install Avoiding revenue shortfalls in the long run depends tubewells and low-lift pumps led to a substantial on identifying the real benefits and costs of reha- increase in the number of tubewells. This helped bilitating the I&D system and getting the beneficia- to control waterlogging from an irrigation-induced ries to recognize the benefits and pay for them. As rising water table and reduced the amount of irri- discussed above, this is best achieved with a PIM gation water required from surface water sources. approach. Although getting irrigation water users Widespread private investment that complements to fully cover costs will result in a sustainable sys- public investment is only possible when credit tem, there are other sustainable pricing systems, is widely available. Microfinance with social col- including ones that don't impose the full cost of I&D lateral, pioneered by the Grameen Bank in on purchasers of irrigation water. Bangladesh but supported by many organizations today, is integral to full engagement of the private For example, downstream water users may be will- sector. ing to help pay for drainage improvements that improve water quality. Thus, irrigators will pay less Recent empirical economic analysis has shown that than the full cost of drainage. Of course, there is an rates of economic growth are higher in countries argument in favor of the "polluter pays principle." with greater income equality. A very plausible ex- But that is not always possible, given historical and planation for this finding is that profitable invest- political conditions, and sharing the costs of a drain- ment opportunities recognized by those closest to age scheme between the polluters and those affected the investments are not always recognized by those downstream can still result in an economically ef- with capital to invest. When greater income equal- ficient solution that is more acceptable to the most ity exists, informal loans from friends, relatives, or powerful stakeholder groups. Any payment system local lenders are more available, allowing these in- where all beneficiaries feel they are getting more vestment opportunities to be captured. Societies with than they are paying, and where all costs are cov- 20 IRRIGATIONANDDRAINAGE REHABILITATION ered, will be sustainable. An innovative cost-shar- the stakeholders in I&D systems. In turn, they can ing example that involved payment by an external put pressure on those who manage the systems to beneficiary for water quantity rather than water recognize and resolve problems before they become quality improvements is presented in Box 4. significant. Feedback loops of this sort are most ef- fective when they are explicitly discussed by stake- CREATE SYSTEM PERFORMANCE holders during conceptual development of a project AND IMPACT MONITORING AND and formalized as a condition of project financing. Identification and strengthening of feedback loops FEEDBACK LOOPS is especially important for control of off-site envi- ronmental impacts. Unfortunately, very few ar- The outcomes of irrigation and drainage rehabili- rangements of this type seem to have been made in tation should be monitored and communicated to irrigation and drainage projects. UNDERTAKING REHABILITATION AND MODERNIZATION Few irrigation and drainage projects in developing The most common reason to consider a rehabilita- countries are reasonably maintained, largely be- tion or modernization of an irrigation project is the cause of inadequate financial resources for main- deterioration of the physical infrastructure of the tenance activities caused by either low government irrigation and drainage system. However, in most budgetary allocations and/or insufficient fees col- cases, this deterioration is only a symptom of the lected from farmers. Even with reasonable mainte- poor performance of the management of the water nance, over a period of time project water delivery system. requirements could change, perhaps as a result of a shift in cropping patterns. Water supply and wa- Most projects never reached their original expected ter quality no longer match the project as originally level of performance. In some cases, they may have planned, and existing facilities need some changes. caused severe negative impacts to the off-site and BOX 4. COST-SHARING FOR I&D IMPROVEMENTS IN THE MPERIAL I VALLEY, CALIFORNIA The Imperial Irrigation District (IID) services approximately 184,000 hectares of irrigated desert in southern California. The district irrigation efficiency is 75 percent, including on-farm losses and conveyance losses. The IID is supplied by canals, most of which were unlined when constructed. All drainage water from the IID ends up in the Salton Sea, a salt sink. Drought-related water shortages in California, population and water demand growth projections, and limits on withdrawals from surface water sources such as the Colorado River and the San Joaquin-Sacramento River Delta have spurred interest in water conservation for both urban and agricultural uses. Because water conser- vation in the IID is less expensive than in the urban areas served by the Metropolitan Water District (MWD), a cost-sharing arrangement was organized in the early 1990s to transfer $150 million from MWD to IID. Funds were spent to modernize IID operations, with the "saved" water being transferred to MWD. Improvements included canal lining to reduce seepage; improved remote monitoring (microwave) of water levels and flows; automa- tion of key canals; increased reservoir storage to buffer the timing of deliveries within IID from the timing of deliveries to IID by external suppliers; lateral interceptors to capture and re-use spills from the ends of lateral canals; and increased training of employees to increase responsiveness to water users' needs and requests. MWD, IID, and environmental groups generally agree that this cost-sharing arrangement is a success. Source: Plusquellec, H. et al. (1994). 21 WATER RESOURCES AND ENVIRONMENT · TECHNICAL NOTE E.2 on-site environment. In most cases, a simple resto- municipal and domestic water use, navigation, ration of the physical infrastructure "as it was" recreation, fish and wildlife--considered? would only repeat the vicious cycle of deteriora- s Was the water supply adequate during drought tion and rehabilitation. A number of donor-financed periods? What was the magnitude and frequency projects during the last two decades have supported of shortages expected? rehabilitation projects consisting mostly of infra- s Was the use of groundwater considered as a structure repairs, such as leaks and rusted gates, water supply component? erosion, and instability of earthworks. However, the s Was the water quality of surface and ground- actual causes of poor performance need to be iden- water adequate for the purposes of the original tified through an in-depth diagnosis. Only a sys- project during the years of operation? tematic diagnosis will provide insight into whether s Were the assumptions regarding conveyance, the project should be rehabilitated or upgraded (Box distribution, and on-farm efficiencies realistic, 5) through physical modifications or whether mana- given the level of control technology of the gerial changes are also needed. irrigation system and the long-term effective- ness of the canal lining design and quality stan- A diagnostic should include first a review of the dards? original objectives of the project to establish a base line for further evaluation, and then an analysis of Subsequent modifications to the original features the existing system. and objectives of the project should be identified. During their operation, many projects are affected The quantity and quality of surface and groundwa- by physical, social, and environmental events. ter resources available to the project when it was Changes in land use, types of crops, and cropping initially conceived and developed should be re- intensities are most frequent. Groundwater largely viewed to determine if such supply was ever made contributed to the intensification of irrigation in available, and if the amount was adequate to meet some alluvial, irrigated areas. Abundant water sup- project demand. Questions concerning the adequacy plies may have decreased considerably due to up- of the original project's water quantity and quality stream irrigation expansion. On-site waterlogging should include: and salinization may have impacted a large por- s Were water allocations for other water activi- tion of the project area. ties--irrigation, flood control, power generation, BOX 5. DEFINITIONS: MAINTENANCE, REHABILITATION AND MODERNIZATION These definitions are based on the ICID Guidelines for rehabilitation and modernization of irrigation projects. s Maintenance, a routine activity, is the process of keeping irrigation and drainage facilities in good working condition so that all parts can fulfill the purpose for which they were originally designed. s Rehabilitation is the renovation or carrying out of remedial work on existing facilities in need of repair, and on those facilities whose performance fails to meet the original criteria and needs of the project. If the original performance criteria were inadequate or no longer meet the needs of the users, rehabilitation by itself could per- petuate the vicious cycle of poor recovery of recurrent cost, inadequate maintenance, deterioration and rehabilita- tion. s Modernization is the process of improving and enhancing an existing irrigation system to meet new perfor- mance criteria. The process includes changes in existing facilities, operational procedures, and institutional aspects. Unlike rehabilitation, modernization is not renovation of project facilities in need of repair. A more specific definition of modernization was adopted during an FAO expert consultation held in Bangkok in 1996: "A process of technical and managerial upgrading (as opposed to mere rehabilitation) of irrigation schemes combined with institutional reform, with the objective to improve resource mobilization (labor, water, economic, environmental) and water delivery service to farmers." 22 IRRIGATION ANDDRAINAGE REHABILITATION The diagnostic of the present performance should described in the first section, many of the problems evaluate whether the project has ever reached its ultimately arise from unachievable policy objectives, objectives in terms of hydraulic, agronomic, eco- inadequate prices for scare water, insufficient man- nomic, financial, and environmental performance, agement capacity, and conflicting institutional ob- including: jectives. Many countries have now instituted reforms s Hydraulic performance: conveyance, distribu- of these institutional and financial issues as part of tion and on-farm efficiency overall rehabilitation of the I&D sector. For example, s Agronomic performance: cropping intensities, the State of Victoria, Australia has undertaken a crop yields comprehensive reform process in its I&D operations, s Economic performance: rate of return including: s Financial performance: cost recovery, farmers s Separating the functions of water resources income. policy development, enforcement of standards, and undertaking technical operations Performance indicators have been developed by s Regionalizingthemanagementofirrigationdis- several organizations (ICID, IWMI, FAO and World tricts Bank/IPTRID) to assess the performance of projects s Encouraging the involvement of local irrigators by comparing inputs and outputs in terms of water in the management of their districts and monetary values. These indicators are useful s Changing the pricing structure for water sup- to determine if a project is performing well com- ply to better (but not fully) reflect the cost of pared with similar projects, or if its performance is operations. deteriorating over time. However, more complex investigations are needed to understand the causes These reforms have allowed greater investment in of poor performance. These include an examina- modern irrigation infrastructure, a more profitable tion of the water allocation, water control strategy, irrigation industry and a more sustainable indus- control equipment, and the performance of the man- try in the long term. agement agency. Thus, irrigation projects aiming to deliver water according to crop requirements Simple infrastructure rehabilitation in the face of through a canal system equipped with manually inadequate institutions and policies is a short-term operated gates or through fixed structures to divide solution that is likely to fail. Experience shows that water inflows according to agreed proportions (flow simple rehabilitation will lead to a cycle of reha- dividers) are doomed to failure--first, because of bilitation, followed by degradation, followed by re- their operational complexity; and second, because habilitation. This cycle can be seen in certain regions they have no capability to adjust to actual water impacted by substantial changes in water supplies needs. Both designs cannot reach the efficiencies and land use--such as Pakistan--or in regions where of more advanced projects. Furthermore, the rigid design criteria are either faulty or unrealistic. Very or unreliable water delivery supplied by these sys- few countries have adopted the full spectrum of re- tems constrains farmers' incentive to adopt on-farm forms to I&D operations. Nevertheless, it is com- water-saving techniques (see Note F.2). mon to find some level of institutional reforms and capacity strengthening included as part of I&D re- THE NEED FOR A NEW APPROACH habilitation projects. Improvements in the respon- TO IRRIGATION DEVELOPMENT AND siveness of I&D management, coupled with changes in water pricing as well as technical improvements, REHABILITATION all contribute toward more efficient and productive I&D systems. Irrigation rehabilitation is not just a matter of im- proving or replacing physical infrastructure. As 23 WATER RESOURCES AND ENVIRONMENT · TECHNICAL NOTE E.2 FURTHER INFORMATION A useful general reference is: Modern I&D systems that show both economically and environmentally improved performance are de- Masood, Ahmad, and Gary Kutcher. 1992. Irrigation plan- scribed in: ning with environmental considerations. World Bank Technical Paper No. 166. Washington: Plusquellec, H., C. Burt, and H. W. Wolter. 1994. Modern World Bank. water control in irrigation. World Bank Techni- cal Paper No. 246. Washington: World Bank. Participatory management of I&D schemes is dis- Langford, K. J., C. L. Forster, and D. M. Malcolm. 1998. cussed, with examples, in: Toward a financially sustainable irrigation sys- tem. World Bank Technical Paper No. 413. Wash- Groenfeldt, D. and M. Svendsen. 2000. Case studies in ington: World Bank. participatory irrigation management. Washing- ton: World Bank Institute. Setting the price for irrigation water as part of re- Oblitas, K. and J. R. Peter. 1999. Transferring irrigation habilitation is described in: management to farmers in Andrha Pradesh, In- dia. World Bank Technical Paper No. 449. Wash- Tsur, Y. and A. Dinar. 1995. Efficiency and equity consid- ington: World Bank. erations in pricing and allocating irrigation wa- Subramanian, A., N. Vijay Jagannathan, R. Meinzen-Dick, ter. Policy Research Working Paper No. 1460. eds. 1997. User organizations for sustainable water Washington: World Bank. services. World Bank Technical Paper No. 354. Skaggs, R. W., M.A. Breve, and J.W. Gilliam. 1994. Washington: World Bank. "Hydrologic and water quality impacts of agri- cultural drainage," in Critical reviews in environ- There have been a number of evaluations of the per- mental science and technology, 24(1): 1-32. formance of I&D schemes, including: Jones, W. I. 1995. The World Bank and Irrigation. OED Department Report. Washington: World Bank. World Bank Operations Evaluation Department (OED). 1996. Irrigation O&M and system performance in southeast Asia: an OED impact study. OED Report No. 15824. Washington: World Bank. Umali, D. L. 1993. Irrigation-Induced Salinity. World Bank Technical Paper No. 215. Washington: World Bank. 24