26327 Water Resources and Environment Technical Note G.3 Wetlands Management Series Editors Richard Davis Rafik Hirji WATER RESOURCES AND ENVIRONMENT TECHNICAL NOTE G.3 Wetlands Management 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 Types of Wetlands 11 Wetlands include such freshwater ecosystems as flood- Author plains, marshes, peatlands, swamp forests, and coastal Joop de Schutter ecosystems such as mangroves, estuaries, and open coasts. They are distinguished by the presence of water; Technical Adviser usually have unique soil conditions that differ from the Stephen Lintner adjacent areas; and support vegetation adapted to a dynamic hydrologic regime. Editor Robert Livernash Threats to Wetlands 11 Half of the world’s wetlands have disappeared since Production Staff 1900. Drainage for increased agriculture production Cover Design: Cathe Fadel is the principal cause. Other wetlands have been de- Design and Production: graded by pollution, invasive species, and alterations The Word Express, Inc. to flows. Many of these impacts originate from the upstream watershed. Notes Unless otherwise stated, Functions and Benefits of Wetlands 14 all dollars = U.S. dollars. Wetlands are some of the most productive ecosystems All tons are metric tons. on earth. They regulate water flows; control sediment and nutrient pollution; provide natural food and fiber for dependent communities; offer productive areas Cover photo by for agriculture and fishing; provide habitat for migra- World Bank tory birds and fish breeding; and support consider- Wetlands in sand dunes, able biodiversity. Namibia This series also is available on the Incorporating Wetlands Management World Bank website into Bank Projects 18 (www.worldbank.org). Effective protection and restoration of wetlands requires involving the various stakeholders; assessing a range of development options; attempting to place a value on the services provided by wetlands; and instituting a monitoring and assessment program. 3 WATER RESOURCES AND ENVIRONMENT • TECHNICAL NOTE G.3 Constructed Wetlands 25 Wetlands can be constructed to provide specific ecosystem functions, particu5larly 5treating and recycling wastewater. Constructed wetlands offer considerable savings in wastewater treatment costs for small communities, as well as providing valuable habitat and areas for public education and recreation. Conclusion 26 Wetlands provide a wide range of ecological functions that support the liveli- hoods of local communities as well as provide regional and global benefits. There is an increasing appreciation of the value of wetlands. Many agencies, including the World Bank, are attempting to preserve and restore wetlands. Further Information 27 Boxes 1. Lake Naivasha: A case of natural pollution control 16 2. Ecotourism in the Ukraine Danube Delta Biodiversity Project 17 3. The Mahanadi Delta, Orissa, India 18 4. The Kihansi Hydro Project and the Spray Toad 20 5. The Pantanal 21 6. Wetland mitigation banking: An innovative approach 22 7. Restoring the deltaic wetlands of the Northern Aral Sea 23 8. Valuing ecosystem services: the Hadejia-Nguru Wetlands 23 9. Integrated coastal zone management indicators in the Baltic Sea region 24 Tables 1. Main wetland types 12 2. Main causes of wetlands loss 13 3. Functions of wetlands ecosystems 15 4. Driving Force Indicator Matrix 25 5. S-R Indicator Matrix 25 4 WETLANDS MANAGEMENT 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 AND ENVIRONMENT • TECHNICAL NOTE G.3 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 The Notes are intended for use by those without emerging topics such as environmental flow assess- specific training in water resources management ment, environmental regulations for private water such as technical specialists, policymakers and utilities, inter-basin water transfers and climate managers working on water sector related invest- variability and climate change. The latter topics are ments within the Bank; practitioners from bilateral, likely to be of increasing importance as the World multilateral, and nongovernmental organizations; Bank implements its environment and water re- and public and private sector specialists interested sources sector strategies and supports the next gen- in environmentally sustainable water resources eration of water resources and environmental policy management. These people may have been trained and institutional reforms. 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 WETLANDS MANAGEMENT ACKNOWLEDGMENTS The production of this Technical Note has been Mackinnon of the World Bank. Maria Isabel Braga supported by a trust fund from the Government of and Colin Rees of the World Bank provided helpful the Netherlands managed by the World Bank Envi- comments on the structure of the Note. Henrik ronment Department. Dissing of the WWF and Gayatri Acharya of the World Bank provided information on the Baltic Sea This Note was drafted by Joop de Schutter of Re- Environment Program and the Hadejia-Nguru wet- source Analysis, the Netherlands. The Note was lands in Nigeria, respectively. reviewed by Hans- Olav Ibrekk and Kathleen 7 WETLANDS MANAGEMENT INTRODUCTION Many wetlands around the world are being lost or there are no feasible alternatives for the project and are under threat. In many cases, losses are caused its siting, and comprehensive analysis demonstrates by direct development activities such as irrigation that overall benefits from the project substantially systems, conversion to agricultural land, reclama- outweigh the environmental costs. These habitats tion for urban expansion, or aquaculture such as include freshwater lakes and rivers, coastal marshes, prawn culture in mangrove systems in South and wetlands, and estuaries. The 1993 Water Resources Southeast Asia. In other cases, it is the result of off- Management Policy notes the need to “protect en- site developments such as excessive upstream wa- vironmental resources in floodplains and wetlands,” ter use, exemplified by the loss of the Amu Darya and the recent Water Resources Sector Strategy rec- and Syr Darya river delta ecosystems in the Aral ognizes that wetlands provide valuable environmen- Sea Basin; water pollution, such as the influence of tal services to dependent communities. An Update the Aswan Dam on sediment deposition in the Nile to the Environmental Assessment Sourcebook2 pro- Delta; or the introduction of invasive species. Wa- vides advice on assessing wetland ecosystems. The ter withdrawals are projected to increase by 18 per- Bank has supported regional wetland assessments— cent in developed countries and by 50 percent in such as the 2000 map of Wetlands in Asia and the developing countries over the next 25 years, so these production of a booklet with Wetlands Interna- threats to wetlands are likely to worsen and have tional—and has invested in projects that include significant impacts on the natural environment and wetland protection and restoration in most parts of human welfare. the developing world. This Note provides technical support to the integration of wetlands management Existing wetlands, such as floodplains and river es- principles into water resources planning and de- tuaries, are often highly productive and play a very velopment, as well as strategic instruments such important role in both ecological functioning and as country environmental analysis. human subsistence.1 The loss of wetlands is pos- ing a significant threat to aquatic biodiversity; more In the next section, we describe the different types than 800 species of plants and animals currently of wetlands and their occurrence in various bio- threatened with extinction are found in freshwater geographic regions. We then describe the rapid loss ecosystems. of these wetlands around the world and the causes The World Bank recog- of this loss. Although nizes the importance of some of this loss can be wetlands in its policies as attributed to natural Photo by Curt Carnemark, World Bank well as in its operations. events, most of it arises OP 4.04 (Natural Habi- from human activities tats) states that the Bank such as land use conver- will not support the sig- sion and diversion of nificant conversion of river flows for agricul- natural habitats unless tural development. The Wetland, Seychelles 1 World Bank (2002) states that the productivity of estu- aries is around 50 times that of grasslands and 8 times that of wheat fields. 2 World Bank (2002). 9 WATER RESOURCES AND ENVIRONMENT • TECHNICAL NOTE G.3 beneficial functions provided by wetlands are ex- of assessing the value of services provided by wet- plained in the following section. The final section lands, the costs of retaining wetlands in develop- provides details of environmental protection (to ments (including mitigation measures), and the avoid loss), planning, and management of wetlands. selection of indicators and a monitoring program to These include adherence to Bank safeguard poli- implement them. cies, full stakeholder participation, the importance 10 WETLANDS MANAGEMENT TYPES OF WETLANDS The “Ramsar Convention3” has defined wetlands as: I Artificial or human-made wetlands, including reservoirs, aquaculture ponds, excavations and areas of marsh, fen, peatland, or water, whether borrow pits, wastewater treatment ponds and natural or artificial, permanent or temporary, with irrigation canals, ditches, and rice fields. water that is static or flowing, fresh, brackish or salt, including areas of marine water the depth of The first two types can occur in a range of land- which at low tide does not exceed 6 meters. scape settings, as shown in Table 1. The third type, artificial or constructed wetlands, will be discussed According to the Ramsar Convention and scientific at the end of this document. Although the Ramsar literature, wetlands can be classified into three main definition allows for coral reefs and off-shore ar- types: eas, we exclude them here and deal only with fresh- I Inland wetlands, including permanent and sea- water and coastal wetlands including tidal areas, sonal rivers, inland deltas and floodplains, per- estuaries, and mangrove areas. manent and seasonal lakes and ponds, marshes, freshwater swamp forests, and peatlands. Wetlands are always distinguished by the presence I Marine/coastal wetlands, including open coast, of water, either at the surface or within the root zone coral reefs, estuaries, tidal flats, mangrove for- and usually have unique soil conditions that differ ests, and coastal lagoons. These wetlands oc- from adjacent areas. Wetlands support vegetation cupy about 8.6 million km2, or 6.4 percent of (hydrophytes) adapted to a dynamic hydrologic re- the world’s land surface (OECD, 1996). About gime; consequently this vegetation tends to be flood- 56 percent of these wetlands are located in the tolerant. tropics and subtropics. THREATS TO WETLANDS There are few exact figures available on the extent Agricultural impacts, water flow regulation, pollu- of wetlands loss worldwide, although experts esti- tion, and habitat destruction or deterioration were mate that half of the world’s wetlands have disap- the predominant causes of degradation and dete- peared since 1900. Drainage for increased rioration of these sites. agriculture production is the principal cause (Table 2). It is estimated that in 1985 alone, drainage of Loss and degradation of wetlands from drainage, wetlands for intensive agriculture caused between alterations to flow regimes, decreases in water qual- 55 and 65 percent of wetlands loss in Europe and ity (see Notes D.1-3) and invasion by alien species North America and 30 percent in Asia, South (see Note G.4) often have far-reaching ecological America, and Africa. In the latter regions, the im- and economic consequences. This is illustrated by pact of agricultural drainage on wetlands is increas- the following examples:4 ing rapidly as growing populations demand more space for food production. Even protected wetlands are threatened or deterio- 3 The 1971 Ramsar Convention on Wetlands of Interna- rating. Disturbances were recorded in some 75 per- tional Importance was established as the first global, in- cent of the almost 957 sites designated as wetlands tergovernmental conservation treaty for wetlands. of international importance (Ramsar Sites) in 1998. 4 Roggeri, H. (1995). 11 WATER RESOURCES AND ENVIRONMENT • TECHNICAL NOTE G.3 TABLE 1. MAIN WETLAND TYPES Character Examples Inland Wetland Floodplain Floodplains occur in alluvial lowlands adjacent The Niger delta in Mali extends over 2 million to rivers with large variations in discharges and hectares during the wet season; during the seasonal or intermittent flooding. They are dry season, it covers only 400,000 hectares. common in tropical rivers with extensive inland Lake Chad is a shallow lake that includes and/or deltaic systems and often possess swamps and marshes. Other examples are shallow lakes and oxbows. Permanent shallow large parts of the Amazon, Lake Naivasha in lakes are characterized by submerged Kenya, Lake Tempe in Indonesia, and the aquatic plants or plants with floating leaves, Inner Delta of the Magdalena River in and seasonal variations in water levels. Colombia. Marsh Marshes are normally dominated by emergent, The Sudd in Sudan is reputedly the world’s rooted grassy vegetation (e.g. grass, reed) largest marsh. Other examples include the characterized by muddy, waterlogged soils. Okavango Delta in Botswana, most of Lake They generally develop in areas where the Chad, and very large areas of the Amazon water level tends to vary considerably. and Congo/Zaire River Basins. Marshes never fully dry out. Peatland Peatlands develop when organic debris Peatlands are found in coastal tropical produced by swamp vegetation is not fully areas—the islands of Sumatra, Irian Jaya, and decomposed as a result of waterlogging, Sulawesi in Indonesia, and Negril Morass in oxygen deficiency, high acidity, low Jamaica—and high-altitude areas such as temperatures, or nutrient deficiency. They the highlands of East Africa, Lesotho, and have high average carbon content; Papua Niuginni. typically 50 percent. Swamp Forest Swamp forests are mainly found along the Swamp forests are found in Southeast Asia lowest shores of water bodies, in depressions (Indonesia, Papua Niuginni, Malaysia), Central or on waterlogged soil. They develop where Africa (Zaire, Congo, Gabon, and the Niger shallow stagnant water occurs during a large Delta), the Amazon Basin, and Central part of the year. Swamp forests never fully America (Costa Rica). dry out. Coastal Wetland Mangroves Mangroves are tidal forests consisting of plant Mangroves are found along the coasts of Asia; formations typically developing on sheltered Indonesia accounts for almost one third of the coastlines. They only occur in tropical and total. Other examples include the Sundarbans subtropical regions. Mangrove tree species on the Bangladesh-Indian border, which is thrive in shallow, variable tidal environments. a well-preserved large-scale mangrove They typically develop where fresh and marine ecosystem; the coasts of Brazil; and several waters meet; both influence local ecosystem Caribbean and West African countries. conditions. Estuary Estuaries occur where river and marine Found in all countries with coastlines. ecosystems meet. They are characterized by variations in water salinity levels and often saline stratification. Estuaries usually include a large variety of wetland habitats, including mangroves and coastal lagoons in tropical and subtropical regions. Open Coast Open coasts are not subject to the direct The Wadden Sea in Northern Europe is an influence of rivers and lagoon systems. example of a wetland on an open coast. They may include habitats such as tidal flats and mudflats and, in tropical/semi- tropical areas, mangroves. 12 WETLANDS MANAGEMENT TABLE 2. MAIN CAUSES OF WETLANDS LOSS Coastal Wetlands Inland Wetlands Freshwater marshes Swamp forest Open Coast Floodplains Mangroves Peatlands Estuaries Lakes Human Actions Direct Drainage for agriculture, forestry, and mosquito control Dredging and stream channelization for navigation and flood protection Filling for solid waste disposal, roads, and commercial, residential and industrial development Conversion for aquaculture/mariculture Construction of dykes, dams, levees, and seawalls for flood control, water supply, irrigation, and storm protection Discharges of pesticides, herbicides, nutrients from domestic sewage and agricultural runoff, and sediment Mining of wetland soils for peat, coal, gravel, phosphate, and other materials Groundwater abstraction Indirect Sediment diversion by dams, deep channels, and other structures Hydrological alterations by canals, roads, and other structures Subsidence due to extraction of groundwater, oil, gas, and other minerals Natural Causes Subsidence Sea-level rise Drought Hurricanes and other storms Erosion Biotic Effects Absent or exceptional= Present, but not a major cause of loss= Common and important cause of wetland degradation and loss= I Flood problems in Colombo, Sri Lanka, wors- eral towns in the lower Perak basin in Malaysia. ened after nearby swamps were filled in. The I Drainage of peat swamps near Bushenyi in drainage of wetlands had a similar effect on sev- Uganda led to serious water supply problems; 13 WATER RESOURCES AND ENVIRONMENT • TECHNICAL NOTE G.3 the drained area is no longer able to store ex- to and from the wetlands and has led to a large cess water and release it evenly during the dry decline in fisheries. season. I Overgrazing and deliberate fires in the peat- These environmental problems and associated costs forming swamps of Lesotho led to considerable occurred because of a poor appreciation of wetland erosion in the Orange and Tugela rivers. ecosystems and the services they provide. Although I Flood levels downstream of the Bakalori Dam there have been few attempts to place an economic in the Sokoto valley, Nigeria, dropped by 50 value on the ecosystem services provided by wet- percent, causing a 53 percent fall in the lands, it is clear that the costs from the loss of wet- floodplain’s cropped area. The loss of agricul- lands can be substantial. For example, an tural production from this modification of the assessment of floodplain productivity in Bangladesh flooding regime has been valued at $7 million concluded that a different operational regime for annually. water flows in rivers and canals of the delta—in line I Construction of the Markela Dam on the Niger with fish migration patterns—could probably double River in Mali has blocked fish migration routes fish productivity. FUNCTIONS AND BENEFITS OF WETLANDS Most wetlands provide multiple resources, prod- species. For example, the Kafue Flats in Zambia ucts, and services—depending on their biological, support a large population of the Kafue lechwe, a chemical, and physical characteristics and the in- wetland antelope unique to this particular flood- teraction among these characteristics. Various meth- plain. The Niger inner delta hosts up to 1.5 million ods have been developed to describe the functions, birds each year, which is 85 to 100 percent of water values, and benefits of wetlands. The Function Value birds recorded in the Niger River Basin. Analysis method5 assumes that the resources, ser- vices, and products provided by wetlands arise from Maintenance of regional water balances is another the four basic functions listed in Table 3 and de- important regulation function of wetlands. Reten- scribed below. tion of water in floodplains will decrease down- stream flood damage by both reducing the height REGULATION FUNCTIONS of flood peaks and diminishing the volume of flood- waters through groundwater infiltration and evapo- Regulation functions describe the capacity of eco- ration. Flood control by wetlands is now being systems to regulate ecological processes that con- rediscovered as a water management tool in many tribute to a healthy environment, such as local parts of the world, including developed countries climate stabilization, water flow regulation, and such as those along the Rhine River in Western Eu- groundwater recharge. These functions are char- rope. In arid regions, wetlands are a critical source acterized by not requiring any human intervention of groundwater recharge (Note G.1). For example, and are usually unnoticed until they are disturbed, each year the floodplains of the Hadejia River Ba- such as increased flooding as a result of wetland sin in northern Nigeria supply around 1.4 x109 m3 drainage. Wetlands provide crucial habitat to a wide range of 5 Originally developed by de Groot, R.S. 1992. Functions species, including mammals, reptiles, amphibians, of Nature. Evaluation of Nature in Environmental Plan- fishes, insects, waterfowl, crustaceans, plants and ning, Management and Decision Making. The Netherlands: many other living organisms. Wetlands also pro- Wolters-Noordhoff. Further elaborated by Koudstaal, R. vide nursery and migration habitat for bird and fish and R. Slootweg (1994). 14 WETLANDS MANAGEMENT TABLE 3. FUNCTIONS OF WETLANDS ECOSYSTEMS Regulation I Flood attenuation and control I Prevention of saline water intrusion I Groundwater recharge and discharge I Protection against natural forces (e.g. climate influences) I Sediment retention I Storage and recycling of organic matter and nutrients I Storage and recycling of toxicants I Regulation of biological control mechanisms I Maintenance of migration and nursery habitats I Maintenance of other wetlands I Maintenance of biological diversity I Storage of carbon dioxide Carrier I Human habitation and settlement I Cultivation: crops, animal husbandry, aquaculture I Energy (solar and hydropower) I Recreation and tourism I Navigation Production I Water as a harvestable resource (drinking) I Naturally produced food and raw materials (e.g. fish, wood, shellfish, salt, etc.) I Fodder and fertilizer I Genetic resources I Medicinal resources I Biochemicals (oil, rubber, tannins, etc.) Information I Aesthetic information I Spiritual and religious information I Historical information I Cultural and artistic information I Educational and scientific information to the Chad aquifer. In some cases, wetlands sup- restored wetland cost $0.67 / kg in 1991, compared port dry-season flows through a delayed release of to $33/ kg for removal via a treatment plant. Wet- floodwaters. For instance, the swamps and lakes of lands such as rice paddies and swamps release a the White Nile supply 83 percent of the water flow- variety of gases such as nitrogen and methane into ing into the lower course of the Nile during the dry the atmosphere through microbially mediated pro- season. cesses and help maintain global cycling of carbon and other elements. Toxic materials, such as agri- The quality of surface and groundwater is also posi- cultural chemicals and some industrial wastes, are tively influenced by wetlands. The vegetation and readily adsorbed/absorbed onto sediments, and so topography of wetlands slows down water flows, can also be removed from rivers when the velocity allowing sediments to settle and nutrients to be re- of water flows diminishes in wetlands. However, moved by both plant uptake and attachment to sedi- these toxicants can then cause ecological damage ments (Box 1). Wetlands can often remove pollutants within the wetlands, unless the wetlands are spe- more cheaply than can engineering solutions. In cifically designed for pollutant removal (see sec- Sweden, for instance, the removal of nitrogen by a tion on Constructed Wetlands). 15 WATER RESOURCES AND ENVIRONMENT • TECHNICAL NOTE G.3 fluence the functioning of wet- lands as a whole. Agriculture that utilizes wet- lands is very important in many tropical wetlands where com- munities have developed tech- niques to benefit from natural conditions, such as flood and flood-recession agriculture and Photo by Curt Carnemark, World Bank swamp agriculture. Develop- ment programs often neglect existing agricultural production, yet it not only supports the live- lihood of indigenous people, but it may also be efficient and sus- tainable. In the Senegal River Elephant, Kenya floodplain, the daily remunera- tion is $1.04-2.00 for flood-reces- Finally, as a result of their high humidity and evapo- sion sorghum, compared to $0.67-1.04 for rice grown transpiration rate, extensive wetlands can influence in irrigation schemes. the local and regional climate. They can have a cool- ing effect if located near highly developed areas, Livestock farmers often lead their herds toward which might reduce impacts of “heat islands” aris- wetlands during the dry season, when upland ing from the heat generated by large urban centers. grasses and water reserves are exhausted. The Utengule Swamp in the Usanga Plain of Tanzania CARRIER FUNCTIONS is an important source of dry-season water supply for over 300,000 head of livestock. The draw-down Carrier functions represent the provision by wet- zone of Lake Chad provides excellent grazing ar- lands of suitable space, substrate, or medium for eas that may annually produce as much as 2 tons human activities such as agriculture, aquaculture, of dry matter per hectare. In Brazil, Paraguay, and animal husbandry, recreation, waterway navigation, Bolivia, the wetlands of the Pantanal support up to tourist sites, and nature protection. Many of these 8 million head of cattle and are some of the most uses change the natural environment and may in- valuable in the world. BOX 1: LAKE NAIVASHA: A CASE OF NATURAL POLLUTION CONTROL Lake Naivasha in southern Kenya has experienced a population explosion from 50,000 to 250,000 people within the lake’s catchment, a major expansion of intensive horticultural industries on the shores of the lake, and clearing and settlement in the headwaters of the lake’s main river. The sewage treatment plant for the town of Naivasha has ceased to operate; raw sewage has been discharged directly into the lake since 1993. In spite of this pollution, water quality in the lake appears to have remained remarkably unaffected, although it may have reached the limits of its assimilative capacity. Nutrient concentrations have remained relatively unchanged; pesticides and heavy metals are detectable in trace amounts only; and sedimentation is not a major problem. The lake apparently has been protected by fringing reed beds, often 20m thick. These have filtered sediments and attached pollutants from riverine and drainage inflows, including the raw sewage. There are constant threats to the reed beds from burning and plans for development of the shoreline. Any major loss of these filters would almost certainly see the lake become polluted, at significant cost to the local economy. 16 WETLANDS MANAGEMENT BOX 2. ECOTOURISM IN THE UKRAINE DANUBE DELTA BIODIVERSITY PROJECT The $1.5 million GEF-funded Danube Delta Biodiversity Project has supported the development of administrative facilities for the reserve, with a small hotel, simple guest houses on the Delta islands, and development of a bird- watching trail. The project also sponsored staff visits at reserves in Europe to learn good practices in self-financing. Since the project was completed in 1999, the Ukraine Danube Biosphere Reserve (DBR) has been developing revenue sources and creating jobs through ecotourism. The DBR has created a special division for ecotourism and offers lodging, food, guides, and auto and boat transport. In order to avoid dependence on the quality of outside tourism firms and to capture a greater share of tourism revenues, the DBR has obtained a license for conducting tourist activities itself. With the money earned thus far, they have built an observation tower and equipped their information center. Source: World Bank. 2002. ECA Biodiversity Strategy . Washington: World Bank. The use of wetlands for tourism and recreation is I The 1987 catch from the seasonal lakes of the growing rapidly. Often wetlands protection activi- Ogan-Komering floodplain in Sumatra was as- ties are combined with ecotourism, which offers an sessed at $15 million. opportunity for cost recovery for much of the in- I In the Niger inner delta in Mali, some 100,000 vestments in nature protection activities (Box 2). fishermen provide around 90 percent of national The Black River swamps in Jamaica draw 50,000 fish production. visitors per year, generate annual revenue of $1 I In the Kulna-Jessore drainage rehabilitation million, and provide jobs for 200 people. In another project in southwest Bangladesh, fish produc- example, the Okavango delta in Botswana and the tion is more profitable than rice cultivation. Kafue Flats in Zambia draw large numbers of tour- ists because of the spectacular range of game. Wetlands, particularly coastal wetlands, also pro- vide a critical spawning area for fish, invertebrates PRODUCTION FUNCTION such as prawns, and other aquatic food. Box 3 de- scribes the attempt to reestablish the productivity Production functions are goods produced naturally of an important fish spawning area in India. in wetlands, as opposed to cultivated plants and animals. Only time and energy are necessary in- INFORMATION FUNCTIONS vestments for their harvest. These goods include water itself, naturally produced food (meat, fruit, Wetlands also provide opportunities for spiritual fish), raw materials (peat and firewood), and ge- enrichment and recreation. Information functions netic and medicinal resources. The natural food, include aesthetic, spiritual and religious, historical water, and energy supply that many communities and archaeological elements, cultural and artistic, depend upon for their existence is included in this educational, and scientific activities. Although the category. For example, local communities harvest value of these functions can be difficult to quantify, 115,000 tons of firewood per year from the Hadejia- it can be large. Nguru floodplain in Nigeria. In the Sudd wetlands in Sudan, hunting provides 25 percent of the meat Wetlands have played a significant role in the de- consumed by local people. velopment of many civilizations; their historical im- portance is enormous. In some areas, many Fisheries are one of the most important activities generations have grown up near and within wet- supported by wetlands. Fish caught in wetlands lands, which are an important feature in their art, provide an important source of protein for commu- literature, and religions. The methods developed by nities around the world. For example: these communities to make sustainable use of wet- 17 WATER RESOURCES AND ENVIRONMENT • TECHNICAL NOTE G.3 BOX 3. THE MAHANADI DELTA, ORISSA, INDIA Over the centuries, the delta and extensive floodplains of the Mahanadi River in the Indian state of Orissa have provided rich fishery resources supported by tidal estuaries with seasonal freshwater and saltwater conditions. The delta wetlands also provided extensive spawning grounds for freshwater prawns and fish. In the later part of the 20th century, the conversion of the delta into irrigated land and changes in the hydrology of the river, particularly the construction of the Hirakud dam upstream of the delta in 1958, have caused many aquatic species to virtually disappear. Indian carp species (Catla catla, Labeo rahita, L. calbasu and Cirrhina mrigala) live in the delta and are totally dependent on monsoon floods for spawning. The more intense the flood, the more fry will be produced. Due to the Hirakud dam and the abstraction of water for irrigation, spawning is virtually absent during years of low rainfall when floods are controlled. Freshwater Macrobrachium prawns also reproduce in the brackish waters of the delta. The hatched juveniles migrate upstream into freshwater areas during a 3-month post-monsoon period. Maintenance of post-monsoon discharge is essential for this activity. The replacement of the deteriorating Naraj Weir by the Naraj Barrage, under the World Bank-funded Orissa Water Resources Consolidation Project, provided an opportunity to improve the fish and prawn breeding potential of the delta. The new barrage will be provided with gates for flow regulation, which could make it possible to manage to some extent the inflows into different branches of the delta. A fish pass—with a width of 2 meters—will be included. The operating rules for the barrage state that, once irrigation requirements are met, the first monsoon floods should be as high as possible to enhance spawning of carp, and that a continuous flow will be maintained through the barrage after the monsoon to allow upstream migration of prawns. The operation of the barrage will be adjusted to maximize these spawning activities as knowledge of flow-biology relationships grows, subject to the requirement that irrigation needs are met. Source: World Bank. 1998. Integrating Freshwater Biodiversity Conservation with Development: Some Emerging Lessons . Environment Department Paper No. 61. Washington: The World Bank. land resources may have great learning potential people have lived for centuries on floating islands for research and possible replication in other re- built of totora reeds. They use boats made from the gions. For example, aquaculture and fishing tech- same material for traveling between the islands. niques developed in the wetlands of Benin are Fish, caught using artisanal methods, provide their striking examples of ingenious traditional tech- animal protein. Even if these techniques are not rep- niques with potential for use in other regions. In licable elsewhere, they contribute to human diver- Lake Titicaca, between Bolivia and Peru, the Uros sity and provide cultural benefits to humankind. INCORPORATING WETLANDS MANAGEMENT INTO BANK PROJECTS Projects that involve wetlands need to follow the same and a monitoring program needs to be instituted to general principles as projects involving other envi- track the success of the implementation ronmental resources: the extent of impact needs to be assessed; the various stakeholders with an inter- IMPACT ASSESSMENT est in the wetland need to be involved; options need to be developed involving different levels of mitiga- The need for wetlands management arises in dif- tion; the costs of wetlands losses need to be estimated ferent types of Bank projects, including: and compared to the benefits from the development I Projects that affect the hydrology of wetlands, under the different options; mitigation measures through such upstream activities as road con- need to be agreed and incorporated into the project; struction, dam developments and irrigation 18 WETLANDS MANAGEMENT schemes, lowering of water tables though Borrowers are required to undertake an Environ- groundwater exploitation for water supply, and mental Assessment (EA) if the project receives an flood control investments. A or B environmental rating.6 Issues arising from I Direct conversion of noncritical wetlands to the proposed development will be identified in the agriculture, ports and harbors, navigation EA, and appropriate mitigation measures will be projects, and aquaculture, especially mangroves included in either the EA or a separate Environ- for mariculture. Under its Natural Habitat Policy, mental Management Plan (EMP). If a project is likely OP4.04, the Bank does not fund projects involv- to affect a wetland located off the site of the project ing significant conversion of critical wetland area itself, an EA should take into account the ex- habitat areas unless there are no feasible alter- isting and future relationships between a wetland natives and the benefits substantially outweigh and neighboring ecosystems. This may necessitate the costs. expansion of the geographical coverage of the EA I Projects that change the water quality and the and generation of sufficient hydrological, ecologi- biological composition of wetlands through cal, and socioeconomic linkages to capture and re- pollution from agricultural runoff, urban and spond to all significant potential social and industrial discharges, introduction of exotic environmental impacts (Box 4). plant and animal species, acid rain, and sea- level rise. The EA should contain baseline data for assessing the potentially positive and detrimental impacts of The Bank’s Operational Policy 4.01 applies to all the proposed project. Because many wetlands func- Bank-funded projects likely to have significant en- tion seasonally, the data should describe the uses vironmental impacts on wetlands, including impacts and services of the wetland over each season. The caused by any of the above effects. Several other poli- EA should include assessments of the importance cies can also be triggered by projects that affect wet- and value of the wetland to affected local commu- lands, including pest management (OP 4.09), water nities and groups, such as women, fishing families, resources management (OP 4.36), indigenous people and livestock owners. (OP 4.20), and involuntary resettlement (OP 4.30). STAKEHOLDER PARTICIPATION When a particular project is likely to impact a wet- land, the following questions should be asked: I Is the area on the Ramsar list, the list of The Bank (and often national laws and procedures) biodiversity hotspots, or any national listing of requires involvement of stakeholders at an early areas requiring protection? stage of major project proposals in most countries. I Will there be significant changes in the ecologi- Usually the Ministry of Environment—but also typi- cal structure and functioning of the wetland? cal development ministries such as Energy, Indus- I Is the project likely to increase nutrients, pesti- try, Public Works, and local and regional water and cides, and other pollutants, or induce physical environment management agencies—must be con- disturbance to the wetland? sulted regarding the application of these laws and I Will any part of the wetland be converted to a procedures. different land use? I What is the present socioeconomic value of the Specific attention must be given to ensuring that wetland? What would be the sustainable yield stakeholder groups, such as local communities de- under better management? What is the replace- pendent on the wetland functions and services, are ment cost if the ecosystem services currently included in the project planning at an early stage. provided by the wetland are destroyed? Communities dependent on groundwater recharged I Are local people willing and able to adapt their traditional practices to the likely changes in wetland functioning resulting from the project? 6 See World Bank 2002. 19 WATER RESOURCES AND ENVIRONMENT • TECHNICAL NOTE G.3 BOX 4. THE KIHANSI HYDRO PROJECT AND THE SPRAY TOAD The Kihansi Hydro Project—a $260 million project to supply electricity to Tanzania—was financed by the World Bank, the Government of Tanzania, the European Investment Bank, and a number of bilateral donors. The project was com- pleted in 2000. Water was diverted from the Kihansi gorge through a tunnel to drive the turbines. Consequently, flows in the gorge have been drastically reduced and the area of wetland in the gorge receiving spray has declined by 98 percent. The project received an A rating and a full EA was carried out. The EA noted that the ecology of the gorge would be significantly impacted by the reduced water flows but, at that time, the existence of the Kihansi Spray Toad was unknown and the project went ahead. The toad was discovered in 1996 when further studies were being conducted for an EMP . Various measures were initiated to save this unique toad. A captive breeding program has been carried out since 2000 at the Bronx Zoo. After some initial problems, toad numbers have now started to increase. A pilot artificial spray system has been installed in the gorge to mimic the effect of the falls and restore some of the original habitat, and hydrological and ecological monitoring has been set up in the area. A search has been mounted for other habitats of the Spray Toad. A new project is being developed to manage the environment in the wetland area. It includes components to build management capacity in government institutions and to educate the general public about environmental issues. Source: World Bank. 2001. Supporting the Web of Life: Biodiversity at the World Bank. Washington: World Bank. from seasonal wetland flooding are potentially just land. It should be guided by well-established prin- as affected by proposals that affect wetland hydrol- ciples of ecological management:7 ogy as those living in the wetlands. Other groups I Principle of Wise Use. As formulated by the such as NGOs, the general public, and business lead- Ramsar Convention, wetlands should be ers may also be included if they have specific inter- sustainably utilized “for the benefit of human- ests in the wetland. kind in a way compatible with the maintenance of the natural properties of the ecosystem.” Failure to involve groups that are highly dependent I Principle of Interdependence. Wetlands cannot on wetlands can impose large, subsequent social be considered independently or as an isolated costs on the project and may even lead to the can- ecosystem. They should be managed on a wider cellation of the project. The protests of ethnic groups ecosystem basis, particularly the watershed against the construction of a large-scale waterway within which they are located, which may cross (Hidrovia) in Brazil led to the licensing process for political and social barriers and different sec- this development being suspended. These groups tors. This includes groundwater systems feed- had not been involved, even though the Brazilian ing the wetlands. constitution guarantees indigenous people the right I Principle of Multiple Use. Sustainable wetland to be consulted regarding water projects that would management means accepting and optimizing affect them (Box 5). the different uses for wetlands and their asso- ciated watersheds. DEVELOPMENT OPTIONS I Precautionary Principle. “It is better to be safe than sorry.” Avoid an activity with an assumed The choice of how much protection and how much detrimental environmental impact, even when development is appropriate for a wetland or sys- scientific evidence cannot yet prove that the tem of wetlands will depend on a range of factors, impact will occur. And if detrimental impacts including alternative uses for the land and water (both upstream and downstream) of the wetland, and the ecological functions supplied by the wet- 7 OECD, 1996. 20 WETLANDS MANAGEMENT BOX 5. THE PANTANAL Bordered by Brazil, Paraguay, and Bolivia, the Pantanal is one of the world’s largest wetlands. It sustains flows in the Paraguay River in both the wet and dry seasons, and supports a diverse assemblage of birds (650 species), fish (400 species), and other biota. Tribal groups, numbering about 150,000 people, are highly dependent on these wetlands for their livelihoods, including food, transportation, and shelter. The wetlands also provide flood control and water purification services to millions of people downstream. In the late 1980s, the governments of Argentina, Bolivia, Brazil, Paraguay, and Uruguay proposed a commercial waterway through the Pantanal to provide year-round navigational access from inland regions to the sea. The eco- nomic study that accompanied this proposal did not include the social and environmental costs arising from the proposed channel straightening, deepening, and stabilization. Subsequent studies showed that the losses arising from reduced wetland flooding and more rapid transmission of flood peaks would substantially offset the economic benefits. Perhaps more importantly, the indigenous groups affected by the proposal mounted a worldwide protest based on their exclusion from the planning of the project. As a result of these concerns, the Brazilian federal environ- mental agency suspended work on the plans within Brazil, and the Brazilian court system agreed that indigenous groups had not been consulted sufficiently as required in the constitution. are to be expected from project activities, check are generated with input from the affected stake- that measures are taken to mitigate impacts, holders. These options can then be assessed for their even if they are not certain. economic, social, and environmental effects. I No-Net-Loss Principle. If a development destroys or impairs an area of wetland after an assess- ECONOMIC ANALYSIS ment shows that there were no feasible alter- natives and the net benefits outweighed the costs, The choice of the preferred development option will then the development plan should seek to re- depend partly on an economic analysis of the ben- tain the functions of the wetland as much as efits and costs of the options, and partly on the so- possible and establish an equivalent wetland cial and environmental values of the wetland. The elsewhere (Box 6). This is consistent with the latter are seldom quantified and incorporated into Bank’s O.P 4.04. the economic analysis, even in developed countries, I Principle of Restoration . Wherever possible, although there is now good guidance on how to do previously degraded wetlands should be re- so.8 Nevertheless, quantification of major ecosys- stored, if it can be shown through studies that tem services can provide important insights into some of the original functions of the wetland which development option is appropriate. For ex- can be reestablished. The creation and restora- ample, an analysis of wetlands in northern Nigeria tion of wetlands is becoming technically and showed clearly that the economic losses to wetland ecologically feasible for a few types of wetland, users from diversion of water to an upstream irri- such as freshwater marshes (Box 7) and tidal gation scheme would at least be comparable to the marshes on low-energy coasts. economic benefits from the new irrigation area (Box 8). Other noneconomic costs, such as social disrup- Project proposals can involve conversion of part or all of the wetland to an alternative use, or an up- stream development that can affect the wetland through changes in flow (including groundwater 8 World Bank (1998). Dixon, J.A., L.F. Scura, R.A. Car- flows), increases in pollution, and the possibility of penter, and P.B. Sherman. 1986. Economic Analysis of En- the introduction of alien flora and fauna species. vironmental Impacts. London: Earthscan Publications. Normally a small number of development options Also Chapter 6 in Belli, P., et al. (2000). 21 WATER RESOURCES AND ENVIRONMENT • TECHNICAL NOTE G.3 BOX 6. WETLAND MITIGATION BANKING: AN INNOVATIVE APPROACH Wetland mitigation banking provides an innovative, market-oriented approach to balancing the pressures for convert- ing valuable wetlands to high-intensity uses with the need to preserve the ecosystem functions provided by wetlands. It is defined as the “restoration, creation, enhancement, and (in exceptional circumstances) preservation of wetlands and/or other aquatic resources, expressly for the purpose of providing compensatory mitigation in advance of autho- rized impacts to similar resources.” If one wetland is to be destroyed through a change in land use, a fully compensat- ing wetland is developed to replace the lost ecosystem services. These “new” wetlands are taken from wetland banks—typically large wetland areas with agreed ecosystem values—under regulatory agency approval. Estimating the value of an ecosystem is not easy and, in practice, most credits and debits have been measured simply in terms of the area of various classes of wetlands. Although area is a crude measure of value, it still allows the loss of many small wetlands to be accumulated into the establishment of a larger, ecologically superior wetland that can be better managed. The approach has proven to be popular in the United States, with over 100 banks now in operation. Most banks are operated by the same organizations, such as state highway departments that are carrying out the land use conver- sion. Until recently, there were few banks operated by the private sector where general developers could purchase compensatory wetland credits. Now, under encouragement from the federal government, several watershed-based wetland initiatives include private or publicly sponsored commercial banks. In spite of its increasing popularity, there are some important unresolved issues with wetland mitigation banking. The timing of receipt of credits is central to full private sector involvement. If mitigation banks are constructed in advance of wetland losses, commercial bank entrepreneurs require that they receive financial credits before replacement wetlands are fully functioning or self-maintaining. Also, the replacement wetland needs to be sustainable in the long term if it is to be truly compensatory. This may require legally enforceable conditions on the long-term management of the replacement wetland. Finally, there are few satisfactory tools available for measuring the ecosystem services provided by a wetland, and so the issue of agreeing on compensation for a destroyed wetland is subject to consider- able uncertainty and negotiation. Source: Davis, M. 1995. “A More Effective and Flexible Section 404.” National Wetlands Newsletter 17(4). tion to groups dependent on the wetlands and dis- MONITORING AND INDICATORS ruption of water-bird habitat, were not quantified. Once a decision has been made about the preferred Economic analysis provides only one of the inputs option, there will need to be monitoring of the im- to the decision regarding which development/con- pacts of the proposed development on the function- servation option to select. To be seen as fair and ing of the wetland. 9 Indicators of wetland have local support, the decision will inevitably be a functioning should be developed as part of the imple- consultative process that must involve all stakehold- mentation process. A monitoring program should ers. Given the diversity of functions provided by be designed during project preparation to gather wetlands and the inter-connectedness of wetlands the information needed to quantify these indicators. with their surface watersheds and groundwater The choice of indicators should be undertaken with systems, it is essential that any interventions that input from local communities so they can become may affect a particular wetland be based on a thor- part of the ongoing implementation and tracking ough understanding of the ecological functions of of the project. the wetland and the consequent sensitivity of those functions to changes likely to be induced by Bank- Wetlands are responsive to many other factors apart funded projects. This is an essential component of from those arising from the development. Conse- making sure that the parties involved in these trade- offs understand the probable consequences of dif- ferent interventions. 9 See World Bank (1998b). 22 WETLANDS MANAGEMENT BOX 7. RESTORING THE DELTAIC WETLANDS OF THE NORTHERN ARAL SEA The decline of the Aral Sea began in the 1960s as increasing amounts of water were diverted—mainly for irrigation— from the inflowing rivers, the Amu Darya and Syr Darya. Between 1960 and 1996, the surface area of the sea declined by some 50 percent and the sea level dropped by 16 meters. In 1990, the Aral Sea split into a small Northern Aral Sea (NAS) and a Large Southern Aral Sea (LAS) as the waters receded. Today, fish production in the Syr Darya delta and the NAS is virtually extinguished, as well as hay production that benefited in the past from natural flooding along streams, lakes, and wetlands. The ecological system has deterio- rated, affecting both people and wildlife. Dust and salt storms occur often, and local climatic changes are taking place around the sea. It is becoming difficult to locate adequate and safe drinking water supplies, and human health problems have increased sharply. Tens of thousands of jobs were lost in the former fishing, agriculture, and service sectors. Huge tracts of agricultural lands were degraded by windborne and waterborne salt from the rivers, soil, groundwater, the desiccated seabed, and dried-up wetlands. The delta area, wetlands, and lakes near the NAS could be rehabilitated by building a dike across the Berg Strait connecting the NAS to the LAS. Using limited local resources, this approach was tested by the creation of a temporary dike in the Berg Strait in 1992 and then again in 1996. It demonstrated that a partially restored NAS will have a much lower salinity than the LAS, thereby improving the environmental situation, improving fisheries potential, and in particu- lar, enhancing the socioeconomic conditions in the area. By rehabilitating the NAS, the project would address the root cause of the environmental degradation in the Syr Darya delta. This would improve agricultural, livestock, and fishery production in the river basin and the delta area. The main environmental benefits of the project include the restoration of the ecosystem and improvements in fishery reproduc- tion conditions in the NAS and in the lakes. The positive impact of the NAS on microclimate and air quality would positively affect soil salinity, soil fertility in the delta area, human and animal health, vegetation, and wildlife. A World Bank-funded project commenced in 2001 to construct the Berg Strait dike, rehabilitate some control structures on the Syr Darya River, upgrade the Chardara Dam, develop the fisheries industry in the NAS, and install a monitoring and assessment capability. Source: Project Appraisal Document (P046045), Syr Darya Control and Northern Aral Sea Phase-I Project. Washington: World Bank. quently, the monitoring program needs to be de- as climate variability and climate change, to be sepa- signed to allow the effects of exogenous factors, such rated from the effects of the development project. BOX 8. VALUING ECOSYSTEM SERVICES: THE HADEJIA-NGURU WETLANDS The Hadejia-Nguru wetlands in northern Nigeria occur at the junction of the Hadejia and Jama’are rivers, downstream of existing and proposed irrigation schemes. During the rainy season, the wetlands are formed by annual flooding of inactive sand dunes. The wetlands are important for wildlife conservation and also support a range of economic activities, including wet-season and dry-season agriculture, fishing, fuelwood collection, livestock rearing, and forestry. Local people also use wild foods from the wetlands for sustenance, and obtain drinking water from shallow aquifers. Through the combined effects of drought and upstream water extraction, the wetlands have shrunk in recent years from 2,350 km2 in 1969 to 413 km2 in 1993. One study put the economic value of the agricultural/fishing/firewood benefits provided by the wetlands at between 846 and 1275 Naira per hectare. A later study put the loss of groundwater recharge benefit for dry-season irrigators at 106,000 Naira per annum, and 1,146,000 Naira per annum for domestic water supply for a 1m drop in groundwater level. The latter study did not include all the environmental benefits provided by recharge, let alone other environmen- tal benefits such as habitat provision for water birds and provision of wild foods for local populations. Overall, the studies show that even these losses from a reduction in downstream wetlands are comparable to, and usually greater than, the benefits from proposed upstream irrigation schemes. Source: Acharya, G. 2000. Approaches to valuing the hidden hydrological services of wetlands ecosystems. Ecological Economics 35: 63-74. 23 WATER RESOURCES AND ENVIRONMENT • TECHNICAL NOTE G.3 Indicators of change such as extent of poverty, annual withdrawals of ground and surface water, or threatened species as a percent of total native species can be used. The United Nations Commis- sion for Sustainable Develop- ment has done much work on indicators to measure sus- tainable development.10 Box 9 gives an example of indica- tors used to monitor the impacts of a wetlands man- Photo by Jane Turpie agement program imple- mented in the Baltic Sea Region with pilot projects in Russia, Latvia, Estonia, Lithuania, Poland, and Ger- Fishermen on the Shire River, Malawi many. It shows how a consis- tent structure can be set up to link causes of scientists, and local residents can be supplemented change—in this example, control of illegal forestry by modern technologies such as remote sensing and and fishing—with the impacts of those changes. It is telemetric data management. Responsibility for important to ensure consistency between indica- monitoring should be clearly assigned to specific tors used for the monitoring programs and indica- institutions or parties, which may be government tors used during the environmental assessment (EA) agencies, NGOs, or private organizations with the process so that changes can be measured from an capacity to undertake the data collection and inter- agreed baseline. pretation. Data are gathered for these indicators through a 10 monitoring program. Field monitoring by rangers, United Nations (1996). BOX 9. INTEGRATED COASTAL ZONE MANAGEMENT INDICATORS IN THE BALTIC SEA REGION The HELCOM Management Programs for Coastal Lagoons and Wetlands, led by the WWF, includes pilot projects in lagoons in Estonia, Latvia, Lithuania, Russia, Poland, and Germany. The main goal of the project is to introduce Integrated Coastal Zone Management (ICZM) principles into the management of the Baltic Sea. Some regions are highly polluted and industrialized, while others have high biodiversity values that are being threat- ened. Many of the problems have not been solved because of lack of institutional capacity. The OECD (Pressure, State, Response) framework was used in the monitoring programs. The indicators were identified through workshops and meetings with the stakeholders. Most important indicators are related to ecotourism; fisheries; hunting, birds, forest, and fauna; pollution and landfills; land and natural resources; and water quality, water treatment, and drainage. A Driving Force Indicators (DFI) matrix (Table 4) shows how problems and their causes are related. In a second matrix (Table 5), the State and Response Indicators (SRI) are linked by “targets” and proposed “actions.” Part of the matrices from the Latvian example are used here to illustrate the principles of the approach. Source: Gladh, L. WorldWide Fund for Nature, Sweden 24 WETLANDS MANAGEMENT TABLE 4. DRIVING FORCE INDICATOR MATRIX Problems Causes Driver Indicators Illegal forest cutting and fishing Lack of controlling bodies I Unemployment rate Lack of coordination I GDP per capita in agriculture No management plans I Coastal area with buildings/total Unemployment area market TABLE 5. S-R INDICATOR MATRIX State Indicators Targets Actions Response Indicators I Number of inspectors Develop local business Launch “business I Number of local enterprises incubator” using business incubator I Management plans Provide control and Establish administra- I Number of new inspectors elaborated YES/NO decisionmaking bodies tion of Kemeri for area National Park I Employment in tourism Establish administra- I Number of training activities tion for the project for local people I Employment in agriculture area Establish fund for the I Percent of local people familiar project area with nature protection idea Hire inspectors CONSTRUCTED WETLANDS Wetlands can be constructed to provide specific eco- costs for small communities and even for upgrad- system functions. In particular, they have been used ing of larger treatment facilities. In addition, these for treating and recycling wastewater, resulting in systems can provide valuable wetland habitat for improved water quality and often valuable wild- waterfowl and other wildlife, as well as areas for life habitat. Although wastewater treatment is the public education and recreation. most common use of constructed wetlands, they can also be used for removal of toxicants and in- Because of the build-up of contaminants in sedi- dustrial wastes and for recharging groundwater ments and aquatic plant tissues, wetlands con- systems. structed for contaminant removal need to be actively managed. Nutrients and other contaminants will Different wetland technologies are now available, be released back into the water as the plants die such as various forms of ponds, land treatment and and decompose unless the wetland management in- wetlands systems. Considerable experience has been cludes periodic harvesting and productive use or gained over the years on improved methods for de- safe disposal of the plant material. Contaminants signing and operating constructed wetlands. This absorbed in the sediments also will be flushed out experience, together with results reported in the re- during large flow events unless the wetland is spe- search literature, suggest that constructed wetlands cifically designed to bypass large flows or the man- offer considerable savings in wastewater treatment agement plan includes removal and safe disposal 25 WATER RESOURCES AND ENVIRONMENT • TECHNICAL NOTE G.3 of the sediments. The health of these wetlands needs Agricultural and industrial chemicals can cause the to be closely monitored, because constructed wet- death of microbes and macrophytes unless the dis- lands can be subjected to large loads of toxic con- charges into the wetlands are closely monitored and taminants that can damage the flora and fauna of regulated. the wetland that provides the ecosystem services. CONCLUSION Wetlands provide a wide range of ecological func- the developed world of the importance of retaining tions that support the livelihoods of local commu- wetlands; options include construction of artificial nities as well as provide regional and global benefits. wetlands for specific purposes (such as treatment They provide food and fiber locally, flood control of effluent), as well as innovative schemes to com- and groundwater recharge regionally, and migra- pensate for any wetlands destroyed by development. tory bird habitat and nutrient recycling globally. In Projects financed by the World Bank can affect wet- the few studies undertaken to date, the economic lands through inundation, conversion to alternate value of these functions is surprisingly high—com- land uses, changes in flow regimes, increases in parable, in some studies, to the benefits from pro- pollution, and drawdown of groundwater. Conse- posed development activities that would have quently, damage to wetlands can trigger a number affected the wetlands. of safeguard policies. The Bank does not support projects that would result in the significant conver- About half the world’s wetlands were destroyed sion or loss of natural habitat, such as wetlands, during the 20th century by agricultural develop- unless there are no feasible alternatives, the ben- ment, urban expansion, pollution, and changes in efits substantially outweigh the environmental costs, river flows. There is an increasing appreciation in and suitable mitigation measures are put in place. 26 WETLANDS MANAGEMENT FURTHER INFORMATION The following texts provide general background on Information on monitoring and indicators can be wetlands: found at: Firehock, K. L., J.V. Middleton, K.D. Starinchak, C. Will- World Bank. 1998b. Guidelines for Monitoring and Evalu- iams and L. Geoff. 1998. Handbook for Wetlands ation for Biodiversity Projects. Environment Pa- Conservation and Sustainability. Gaithersburg, pers No. 65. Washington: World Bank. MD: Izaak Walton League of America. United Nations. 1996. Indicators of Sustainable Develop- Acreman, M.C. and G.E. Hollis, eds. 1996. Water Manage- ment: Framework and Methodologies. New York: ment and Wetlands in Sub Saharan Africa. Gland, UNCSD. Switzerland: IUCN Wetlands Programme. OECD. 1996. Guidelines for Aid Agencies for Improved The following reference provides a good overview and Sustainable Use of Tropical and Subtropical on constructed wetlands: Wetlands. Paris: OECD. Roggeri, H. 1995. Tropical Freshwater Wetlands: Guide to Current Knowledge and Sustainable Management. Hammer, D.A. ed. 1990. Constructed Wetlands for Waste- Dordrecht / Boston / London: Kluwer Academic water Treatment: Municipal, Industrial, Agricul- Publishers. tural. Chelsea, Michigan: Lewis Publishers. Information on wetland assessment can be found Some useful websites dealing with wetlands include: in: IUCN Wetlands Programme http://www.iucn.org Koudstaal, R., and R. Slootweg. 1994. Wise Use of Wetlands: A Methodology for the Assessment of Functions Ramsar Convention Bureau and Values of Wetlands. Delft, The Netherlands: http://www.ramsar.org The Wetland Group. World Wide Fund for Nature Howe, C.P., G.F. Claridge, R. Hughes and Zuwendra. 1991. http://www.panda.org Manual of guidelines for scooping EIA in Tropi- cal Wetlands. PH PA/AWB Sumatra Wetland Wetlands International Project Report No. 5. Asian Wetland Bureau. http://www.wetlands.org Bogor, Indonesia: Department of Forestry, Indo- US Society of Wetland Scientists nesia. http://www.sws.org/ World Bank. 2002. Wetlands and Environmental Assess- ment. Environmental Assessment Sourcebook Update No 28. Washington: World Bank. Two useful documents on assessing environmen- tal values provided by wetlands are: World Bank 1998a. Economic Analysis and Environmen- tal Assessment. Environmental Assessment Sourcebook Update No. 23. Washington: World Bank. Belli, P., J.R. Anderson, H.N. Barnum, J.A. Dixon and J-P Tan. 2000. Economic analysis of investment op- erations: analytical tools and practical applica- tions. Washington: World Bank. 27