This report investigates the dynamics of one of the most common agricultural water management practices of sub-Saharan Africa, i.e., small reservoirs. Small reservoirs dam permanent or temporary river flows and support multiple livelihood activities (livestock watering, crop cultivation, fisheries, small handicrafts, etc.) while providing water-related ecosystem services (soil and water conservation, flood and drought mitigation, etc.). Gathering evidence from four sub-Saharan countries, Burkina Faso, Ghana, Ethiopia and Zambia, this report calls for revisiting our understanding and assessment of the costs, performance and institutions for the management of small reservoirs. A more holistic analytical approach is the first step towards an integrative governance framework. This, in turn, holds the promise of sustainable management of small reservoirs.

Drylands cover more than half sub-Saharan Africa and are home to nearly 50 percent of the region's people. This review documents resilience to climatic variability of fish resources in the sub-Saharan drylands. It also examines the potential for increasing their supply through improved use of available bodies of water, especially small reservoirs.

By affecting evapotranspiration and influencing how water is routed and stored in a basin, forests, wetlands and floodplains play a crucial role in the hydrological cycle. Although they are widely attributed a major role in regulating flows (i.e., both attenuating floods and maintaining flow during dry periods), these services are rarely factored into the planning and management of water resources. One reason for the failure to include them is lack of understanding. Very often the extent to which natural regulating functions really occur is unclear. Against this background, this report describes a simple, pragmatic approach for quantifying the flow regulating functions of natural ecosystems. The method has been applied at 14 locations in the Zambezi River Basin.

This book is a printed edition of the Special Issue "Earth Observation for Water Resource Management in Africa" that was published in Remote Sensing

By mitigating the vagaries of climate variability, agricultural water storage is widely anticipated to make a key contribution to climate change adaptation in Africa. However, if the planning of water storage is not improved, it is likely that many investments will fail to fully deliver intended benefits. This report describes the agricultural water storage continuum and some of the possible implications of climate change. A simple diagnostic tool which can be used to provide a rapid evaluation of the need and effectiveness of different water storage options, under existing and possible future climate conditions, is presented.

The Volta River is one of the major rivers in Africa. In this study, a dynamic regional climate model (CCLM), a hydrological model (SWAT) and a water resource model (WEAP) were used to provide an assessment of one downscaled ‘middle impact’ climate change scenario on the performance of existing and planned irrigation and hydropower schemes. The results indicate that, by the middle of the twenty-first century, altered climate is likely to undermine the technical performance of existing and planned reservoirs, which will, in turn, affect development outcomes. Future water resources development in the basin requires interventions that bolster resilience and water security. Much more systematic planning of water storage, greater cooperation between the riparian states and consideration of innovative approaches to water storage are needed.

As we enter an era of increasing water scarcity, there is a growing interest to find ways to capture and put water to more productive uses. Substantial increases in the productivity of water in agriculture are needed to meet the demands for food and ensure environmental security, and to satisfy the demands for non-agricultural uses. However, increasing water productivity in rice-dominated agriculture is a function of the irrigation infrastructure, advances in rice-plant breeding, and the physical, institutional and socioeconomic environments. This paper first describes the potential ways in which increased water productivity can be achieved in the context of rice production in Asia. It then illustrates the ways in which the differences in the environmental context affect the ability to increase water productivity, the approaches used and the incentives to do so. This is explained using two ‘case studies’ reflecting the experiences of Taiwan and the Philippines over the past half-century.

More than 1 million hectares of urban land in India could be irrigated for crops if wastewater was made safe for use. Lack of systematic data collection by municipalities makes it difficult to accurately assess the wastewater generation or estimate the total amount of urban area under wastewater irrigation, so the potential of urban and peri-urban farming could be even greater. This study attempted to analyze the current status of wastewater generation, its uses and livelihood benefits especially in agriculture, based on national data and case studies from Ahmedabad, New Delhi, Hyderabad, Kanpur and Kolkata.