Although irrigation projects often provide water for more than crop irrigation, water allocation and management decisions often do not account for nonirrigation uses of water. Failure to account for the multiple uses of irrigation water may result in inefficient and inequitable water allocation decisions. Decision-makers often lack information on the relative economic contributions of water in irrigation and nonirrigation uses. This report addresses this problem. It examines the relative economic contributions of irrigated agriculture and reservoir fisheries in the Kirindi Oya irrigation system, located in Southeastern Sri Lanka. The results of the analysis indicate the importance of both irrigated paddy production and reservoir fisheries to the local economy. They also demonstrate significant potential financial and economic gains to irrigated agriculture from improvements in water management practices. Since these water uses are interdependent, policy makers must consider how changes in water management practices may affect reservoir levels and water quality and the fisheries that depend on them.

Today, raising capacity in water resources management entails supporting stakeholders and decision-makers to reach a common understanding on the priorities and necessary arrangements for sharing and allocating water-related goods and services. Valuation is central to this process, as setting priorities and making choices implies valuing certain uses and arrangements above others. Water valuation can help stakeholders to express the values that water-related goods and services represent to them. It also offers a means for conflict resolution and planning, informing stakeholders, supporting communication, and facilitating joint decision-making on priorities and specific actions. This report confronts concepts from the literature on water valuation with practical experiences from three local cases where an effort was made to embed existing valuation tools and methods in ongoing water resources management processes. It uses the lessons from this exploration to provide a first outline for a stakeholder-oriented water valuation process. This is expected to provide a useful starting point to help water professionals and policy-makers improve the use of water valuation as a means to support participatory processes of water resources management.

The purpose of this report is to produce a review on water resource valuation issues and techniques specifically for the appraisal and negotiation of raw (as opposed to bulk or retail) water resource allocation for agricultural development projects. The review considers raw water in naturally occurring watercourses, lakes, wetlands, soil and aquifers, taking an ecosystem function perspective at a catchment scale, and takes account of the demands from irrigated and rainfed agriculture. It is hoped that the review will have particular application to developing countries where agreed methods for reconciling competing uses are often absent, but nevertheless takes account of valuation approaches that have been made in post industrial economies.

Thousands of small irrigation reservoirs (tanks) exist in rice ecosystems in malarious regions of south Asia. The potential of these tanks to generate malaria-transmitting mosquitoes has not been adequately evaluated. Through a study of nine small irrigation tanks in north-central Sri Lanka, this report provides an assessment of the capacity of tanks to generate malaria and nuisance mosquitoes, factors that contribute to mosquito generation, and measures that could ameliorate the problem.

This report reviews several decades of global experience in transferring management of government-run irrigation systems to farmer associations or other nongovernmental agencies in an attempt to apply the lessons of success to the African smallholder irrigation context.

Smallholder irrigation systems–where farm sizes generally range from a fraction of a hectare to 10 hectares–pose special management problems, especially where the water available for irrigation is frequently less than the demand. The intensity of system adjustments required to meet individual farmer demands, and the administrative complexity of measuring and accounting water deliveries have generally proven excessive when attempting to meet “on demand” schedules, resulting in chaos (often characterized by illegal tampering with infrastructure, and vast differences of water use intensity at different locations in the system). The alternative–provision of a simple service, based on proportional sharing of available supplies on the basis of landholdings–has been resilient for many years over vast areas. The approach is based on a clear delineation between the part of the irrigation system that is actively managed (at various flow rates and water levels) and the part of the system that operates either at full supply level (with proportional division of water down to the level at which farmers rotate among their individual farms), or is completely shut. This operational design is known as a “structured” system, and has well-defined hydraulic characteristics, simplifying operation and management, in turn allowing a clearer definition of water entitlements and the responsibilities of agency staff and farmers. The approach is particularly suited to areas where water is scarce and discipline is needed to ration water among users. An additional benefit, which has been demonstrated in modeling studies using a well–proven model relating to water and yield, is that the productivity of water (which is more important than the more traditional productivity of land when water is scarce) is substantially increased when deficit irrigation is practiced–a widely observed and predictable response to rationed water supplies. Structured systems are most suited where water is scarce, clear definition of water entitlements is needed, management capacity is limited, and investment resources are limited. The approach to determining critical aspects of a structured system design is described in this report.

A growing body of evidence on the impacts of irrigation management transfer (IMT) shows that IMT risks aggravating rural poverty. For governments that aim to continue irrigation management while ensuring that it contributes to poverty alleviation, a "pro-poor" mode of IMT needs to be designed and implemented. That is, a mode of IMT that benefits poor farmers while benefiting non-poor farmers equally, or perhaps to a lesser degree. The present research explores the scope for pro-poor modes of IMT in canal irrigation, focusing on large-scale canal irrigation schemes in India.