Approximately half of the irrigated area of Iran falls under different types of salt-affected soils and average yield losses may be as high as 50 percent. Slightly and moderately salt-affected soils are mostly found on the piedmonts at the foot of the Elburz (Alborz) Mountains in the northern part of the country. The soils having severe to extreme salinity are predominantly located in the Central Plateau, the Khuzestan and Southern Coastal Plains and the Caspian Coastal Plain. The process of salinization of the surface water resources is mainly due to natural conditions, and to a lesser extent, to the discharge of drainage water into the river systems. Estimates show that about 6.7 km3 of brackish water flow annually through 12 major rivers. There is no straightforward solution to the complex problems of salt-induced soil and water resources degradation in Iran. The approaches addressing the management of these resources need to be multidimensional and must take into account biophysical and environmental conditions of the target areas as well as livelihood aspects of the associated communities.

This report is prepared based on a collaborative research project titled "Impact of Irrigation on Poverty and Environment". The overall project focuses on understanding the crucial role that water, in conjunction with other factors, needs to play to reduce poverty and food insecurity, while maintaining an environmental balance. The research promotes irrigation development that will enhance positive impacts such as poverty alleviation and minimize negative impacts such as environmental degradation. In this report, documentation and information for 12 irrigation systems totaling about 22 sites/schemes have been identified. The common characteristics of these schemes have been provided in this report, with a view of having comprehensive information on the selected case study sites based on rapid appraisal, secondary data and site visits.

This working paper provides results of a broad assessment of water resources and a database of irrigation development and potential in Ethiopia. The country is blessed with ample water resources in central, western and south western parts, while most of northeastern and eastern parts of the country are relatively dry. Hence, despite abundance in some parts of the country, there is high water-scarcity due to lack of water control infrastructure. Given the amount of water available, it is evident that the promotion of water development technologies, especially irrigation, can provide an opportunity to improve productivity of land and labor and increase production volumes. To utilize the advantages of irrigation development, Ethiopia is increasingly investing in this sector. However, there is no clear information and database available. This paper responds to the information requirement on the database of water resources, its potential, extent of irrigation development, and status.

The groundwater present in the hard rock region of the dry zone of Sri Lanka is made up of the shallow 'Regolith Aquifer' and the deeper fracture zone aquifer is now clearly recognized. However, up to now no study had been carried out or reported in this country on the dynamic nature of this shallow regolith aquifer. This is the very first study carried out and reported in this regard. As part of the study, the impact of the Mau Ara trans-basin canal on the groundwater conditions below the area of influence of this trans-basin feeder canal has also been examined.

Similarly to other water demands, environmental water demand (Environmental Flows - EF) also has an economic value and cost. However, few studies have directly considered these costs to date. In this paper, the Menik Ganga (River) in southern Sri Lanka is used as a case study to attempt to evaluate the costs and benefits of EF. The EF components evaluated include the needs of the religious festival at Kataragama, the requirements of the Yala National Park, the requirements of the Pilinnawa Wetland and the requirements of the Yala Marine Protected Area and the Yala Fishery Management Area. Estimates are based on use values of EF such as marketed goods and recreation. For some components multiple estimates have been attempted. A cumulative value of individual EF components is calculated and discussed. It is anticipated that valuing the benefits of EF, in the Menik River or in similar other basins in Sri Lanka and elsewhere, would strengthen the decision making process of water allocation in the future.

Catchment monitoring has always been important to water resources managers and scientists in the development and implementation of effective water resources management strategies. The establishment of a catchment monitoring network involves a process, from the inception of the idea to the actual construction/installation of various structures and instruments while engaging relevant stakeholders especially the local community. In many cases, such a process is not documented, even though it is crucial to do so in order to share such experiences for the benefit of other stakeholders, including researchers, who may wish to undertake a similar exercise. Despite numerous field challenges (social, scientific and engineering), this report strives to document a successful process of establishing a detailed catchment monitoring network in the midst of a rural community inhabited by smallholder farmers, the Potshini community, in the KwaZulu-Natal province of South Africa.

Dam planners and operators often have to consider a huge number of factors and conflicting objectives. This makes decision making extremely difficult. In such situations, decision support systems (DSS) have an important role to play. Over the years, many different DSSs have been developed for dam planning and operation. This report presents a review of the different types of DSS and their application in water resource management. Although some information and examples have been obtained from elsewhere, the main focus is Africa. The report is not a comprehensive compendium on DSS application in dam planning and operation, but rather, it provides an overview and framework for understanding issues pertaining to decision-making in relation to large dams in Africa.

Iran is facing a serious water scarcity and the Government of Iran is trying to implement technical and institutional measures to meet the challenge. One of the key strategies being persuaded by the Iranian authorities is the devolution of management responsibility to users. Thus, irrigation management transfer (IMT) has been adopted as a key strategy to improve the operation and maintenance, and thereby reduce losses, and enhance the sustainability of irrigation infrastructure. However, IMT efforts are at an inception stage and are largely happening in areas where infrastructure is under rehabilitation. The key objective of this paper, thus, was to review the ongoing IMT efforts in the two provinces of Iran, including the much publicized experiences from irrigation systems in the Qazvin Province, as well as the lessons from the neighboring countries, and propose a viable framework for implementing IMT.

This paper provides a synopsis of environmental and health impacts arising from agricultural water development in sub-Saharan Africa and recommends ways to increase the sustainability of investments in irrigation by giving greater prominence to health and environmental concerns. The paper presents a conceptual framework for considering environmental and health issues in tandem; reviews current environmental and health assessment tools; describes national and donor policies; and analyzes current constraints to successful environmental and health planning and management. On the basis of findings, it makes recommendations to improve planning and management across a range of scales. The recommendations are of relevance to both water and agricultural planners and are timely, in the light of recent calls for significant increases in irrigation investment as a contribution to achieving the Millennium Development Goals.

Being able to assess the ability of a catchment to satisfy potential water demands is crucial for water resource planning. In this study, a scenario analysis approach was used in combination with the Water Evaluation and Planning (WEAP) model, to assess the impacts of possible future demands on the water resources of the Olifants River catchment, South Africa. The WEAP model was used to simulate water demand in five different sectors; rural, urban, mining, commercial forestry and irrigation. For each scenario the model provided data on unmet demands and the impacts on river flow. The implications of construction of new water infrastructure and improved demand management were assessed. The study illustrates the value of scenarios linked to simple modeling tools, to provide insight for resource planning.

This working paper presents the results of the Pakistan Component of the Rice-Wheat Consortium Project on 'Sustaining the rice-wheat production systems of Asia'. Rice and wheat crops are main sources of human food and substantially contribute to feeding livestock. The advent of the green revolution in the 1960s resulted in a tremendous increase in the production of these two cereal crops and the rice-wheat cropping system emerged as a very important source of food supply in South Asia.

This study has tried to look into the various aspects of introduction and use of MUS and its effect on the household and the community to identify factors for up-scaling. Due to the unavailability of benchmark data, the assessment of the schemes is based on the information obtained from the respondents for the before and after situations.

This study carried out towards the end of 2004 in two irrigation schemes of contrasting socioeconomic and physical scenarios analyzes the factors that influence the formation of FWUCs under different physical, socioeconomic, legal and institutional conditions. In this analysis it was found that the favorable socioeconomic conditions, appropriateness of the strategies and the process followed and link with the local institutions were the key attributes for the formation of functional FWUCs in the implementation of PIMD.

A major drawback of India's agriculture, watershed development and irrigation strategy has been the neglect of relatively wetter catchment areas and the tribal people living therein. Investing in small-scale interventions for improved water control can produce a dramatic impact on the productivity and dependability of tribal livelihood systems.

This Working Paper reports on research carried out in the Volta River Basin, by the research team in that basin implementing Project number 47, supported by the Challenge Program on Water and Food. The Project title is "Transboundary Water Governance for Agricultural and Economic Growth and Improved Livelihoods in the Limpopo and Volta Basins: Towards African Indigenous Models of Governance." A companion Working Paper (Earle et al. 2006) is being produced reporting on similar work in the Limpopo River Basin.

The paper reviews the existing tools methods and general literature which deal with the construction of climate change (CC) scenarios and with the assessment of impacts of these scenarios on water resources. It further examines the existing CC predictions specific to Morocco. The paper further describes the publicly available hydrometeorological time series data, which could be used to quantify the future CC scenarios for a river basin in Morocco (Oum er Rbia) and a smaller irrigation scheme within it (Tadla), located in the western part of the country. The data indicates that the impact of future CC on water resources at smaller scales such as smaller river basins, specific water resources and irrigation systems has to date not been properly addressed and, therefore, constitutes a niche for immediate research.

Rapidly increasing population in the dynamic semi-arid agro-ecosystems in sub-Saharan Africa (SSA) highlights the necessity to increase food production, while at the same time safe-guarding other ecological systems that support human development and well-being. In the past, increases in crop production to keep pace with population growth in this region were largely achieved through the expansion of cultivated area. Today, we must also consider ways of improving the productivity of already existing cropping systems. This working paper frames the critical questions that must be addressed through development-oriented research and describes the integrated research approach of the SSI program, its interconnected research projects - their scope and methodologies.

This paper is based on a study of Asia's water sector institutions. The main objective of this regional study was the development of a set of action plans for effective water management institutions in a number of selected Asian countries. The study concluded that there was no single best institutional model to satisfy all situations. Institutional requirements for water management vary depending on a number of environmental conditions, which are mainly determined by the stage of development of the country's water sector. Institutions evolve depending on the water-related issues that the sector faces, as the water resources are gradually developed and utilized. Thus, effective water sector institutions are basically demand driven.

In many developing countries, their governments dominate the field of water resources management. Even in "participatory irrigation management" efforts, the governments play a dominant role. As these efforts are rarely based on any internally generated demand from the water users, they usually fail to create viable organizations at the local level. A similar setback can be seen in the more recent institutional reforms in Asia's water sector, which are promoted by the donor agencies and, national and international development professionals. A survey of experiences in Asian countries shows that no country has successfully completed establishing new water sector policies and laws and river basin organizations, as prescribed.

This paper is based on a study conducted in Isiolo District of Kenya between 2002 and 2003 in collaboration with Jomo Kenyatta University of Agriculture and Technology; the Ministry of Water Resources Management and Development-District Water Office, Isiolo; the Ministry of Agriculture and Livestock Development-Isiolo and Meru Dryland Farming Project. The study received the support from Catholic Organization for Relief and Development (Cordaid). The International Water Management Institute (IWMI) provided support for the preparation of this publication. Names of government ministries have been retained as they were at the time of the study.

Agriculture is the most important economic activity in sub-Saharan Africa (SSA) supporting over 67 percent of the population, but 60 percent of these depends on rain-based rural economies, generating in the range of 30-40 percent of the countries' GDP (World Bank 1997). However, rainfall is poorly distributed, ranging from 1,430 mm per annum in central African countries to about 71 mm in arid countries (ECA 2003).

This study examines the potential for water harvesting and conservation against drought in the Indian state of Rajasthan. It indicates that despite water resources depletion, the state still has significant potential for harvesting and conserving water if an integrated water resources management approach is adopted, and proper policies and investment actions are implemented using recent technologies.

This paper focuses on the Walawe River basin, located in a semi-arid zone of southern Sri Lanka. The two major reservoirs in the upstream and middle reaches of the river with a total capacity of 486 million cubic meters (MCM) have significantly affected the hydrology of the river, with associated adverse environmental and social consequences.

This paper integrates the ideas and findings of four presentations in the section "Community Successes" at the Nairobi NEPAD Regional Conference and those of the facilitated discussion sessions during the conference. The four presentations are also documented in the following chapters. We will focus here particularly on "lessons learned" with respect to outscaling (more of the same) and upscaling (expansion to larger regions and higher levels of governance) of such successes.

This document provides a preliminary understanding of the poverty reduction impacts of a range of agricultural water development interventions in sub Saharan Africa, including lower cost alternatives to conventional irrigation investment projects, identifies factors that constrain the poverty reduction impacts of projects and technologies, and derives conclusions and recommendations useful for further water resources development planning in the region.