Publications

The aim of the set of modules is to cover useful elements of AWM from estimating runoff at micro and small watershed level up to irrigated field water management. The modules thus aim at covering water availability estimnation, water control and management, soil-water-plant relationship, water lifting and conveyance and irrigation methods. Each module is divided into a number of chapters and illustrated with figures, tables charts and examples. The modules are also useful as a reference and teaching material at technical, vocational, educational, and training centres and as a field guide. The publication extensively use existing knowledge in the form of texts, figures, demonstration materials derived from various sources such as books, grey literature such as web material, reports, manuals etc. specifically they have immensely used materials from FAO, ICRISAT and IWMI documentations with or without citation to the specific references.

Rainfed agriculutre in Ethiopia is constrained by temporal and spatial variations in climate and severe land degradation caused by soil erosion that is exacerbated by lack of appropriate technologies. The continued shrinking per capita agriculutral land due to population growth and diminishing land quality challenges the livelihood of the communities. This requires multifaceted and targeted interventions. Testing and scalling up of interventions require a relatively uniform system, but the basin’s potential and constraints for crop and livestock productivity is hetrogenous. Farming systems are often taken as important entry point for scaling up of agricultural technolgies. Based on secondary data on climate, soil, crop and livestock, and the master plan of the subbasins, this study clustered and mapped the major farming systems and subsystems in the Nile Basin. Two major systems, the mixed crop-livestock farming and the pastoral/agropastoral livelihoods have been identified. The former was sub-grouped into the cereal based, coffee-tree crops complex and the enset-root crops complex subsystems. The cereal based system was further classified into the single cropping, double cropping and shifting cultivation subsystems, each of which was subdivided based on the dominant crop. The current productivity of the major crops in each farming systems was analysed and found to be lower than not only their potential but also their national average. However, some selected soil, water and crop management technologies have shown substantial yield increase. Thereore, it is believed scaling up of proven tachnologies within a farming system can substantially enhance crop yield and imrpove livelhood.

This paper gives an overview of water resources, its availability and use, problems and constraints, the present and future challenges and the ensuing opportunities in water resource sector of one of the most populated river basins of the world; the Indus-Gangetic basin. Large-scale development of water resources in the Indus basin has led to the resource base being depleted, both in terms of quantity as well as quality. Well-developed surface irrigation systems in the Indus basin tap most of the surface water available in the basin, leaving only 10% of the net runoff to the sea, whereas from Ganges basin, the net runoff flowing to the sea is about 40%. Groundwater, which is expected to serve as buffer source to compensate for the reduced surface water availability, is also getting depleted. Energy and agricultural sector policies followed also favour large scale exploitation of groundwater resources in the basin, which has led to water table decline and a reduction in environmental flows. In the Gangetic part of the basin, it is the economic water scarcity which is more prominent. Equally important is the deterioration of water quality of Ganges river, especially when it flows along the plains accumulating municipal, industrial and domestic waste from the rapidly growing cities situated along its banks. Compounded with these issues is the role played by climate change. Since both Indus and Ganges rivers are heavily dependent on snow and glacier melts, the streamflow in these rivers is highly sensitive to climate change. Recent years have witnessed some responses to the water scarcity problem in IG basin the form of popularization of resource conservation practices, growing high yielding short duration varieties of paddy, micro and precision irrigation, regulations to control groundwater use and management. The article presses the need for water resources in the basin to be managed in a conjunctive manner, considering rain water, surface water, soil water and groundwater in continuum. Considering the inter-linkage between groundwater extraction, energy and food policies, groundwater management strategies should have a focus on energy pricing, food pricing and procurement policies also. Nevertheless, devising long-term strategies on water resource management in the basin need not overlook the likely impacts that the changing climate is going to have on water resources.

Water demand management, or making better use of the water we have - as opposed to augmenting supply - is increasingly proposed as a way of mitigating water-scarcity problems. Moving water away from agriculture to uses with higher economic value is one of the main measures widely seen as desirable. Sectoral “allocation stress” is seen as resulting from the disproportionate share, and inefficient use of water in the agricultural sector. This apparent misallocation is often attributed to the failure of government to allocate water rationally. This paper revisits this commonly-accepted wisdom and examines the nature of urban water scarcity, showing the importance of economic and political factors, shaped by incentives to decision-makers, and sometimes compounded by climatic conditions. It shows that cities’ growth is not generally constrained by competition with agriculture. In general, rather than using a narrow financial criterion, cities select options that go along the “path of least resistance,” whereby economic, social and political costs are considered in conjunction. The question of allocation stress is thus reframed into an inquiry of how transfers effectively occur and can be made more effective.

Underpricing of irrigation water is frequently identified as a primary cause of excessive use of water for irrigation. Higher prices are believed to have the potential to promote conservation. Changes in user behavior are predicated on a quantitative relationship between water charges and the volume use, but volumetric management is quite rare in practice. This paper reviews irrigation schemes that combine conditions of water scarcity and volumetric pricing, either at the bulk or individual level, and provides clear evidence that scarcity is almost invariably dealt with through the definition of quotas. In contrast to the large theoretical literature that has promoted price-based regulation as a key instrument of water demand management, it appears that prices are mostly used to regulate use at the margin, beyond the quota, rather than for rationing scarce water. This is an important role but one that falls short of efficiency pricing. The advantages and drawbacks of quotas are discussed, and an interpretation of why they are selected in practice is given.

In the last two decades water has clearly moved from the purview of experts and engineers to a wider forum where stakeholders articulate different claims, values and interests around water management issues. This article takes the example of current debates on water resource development in the Mekong basin and re ects on what are the current challenges, the visions of the future that are in con ict and the skills available. It re ects on the extent to which new practices have been incorporated in water-related decision-making and reviews the implications in terms of skills needed for tomorrow’s water management.

The concept of a river basin as a management or planning unit has gone through several stages and is in a state of flux. From its western ‘‘discovery” in the 18th century to its advent as the overriding concept behind European water policy, the river basin has been conjured up and mobilized in evolving contexts with varying intentions. Associated with utopian ideas of the late 19th century, it supported ideas of full control of the hydrologic regime and multipurpose dam construction in the 1930–1960 period, then partly faded and was revived to address water-quality problems, before reemerging in the 1990s as the cornerstone of Integrated Water Resources Management (IWRM), enriched and blended with watershed- and ecosystem-management approaches. This article recounts the evolution of the concept of a river basin and how it has been associated with various strands of thinking and sometimes co-opted or mobilized by particular social groups or organizations to strengthen the legitimacy of their agendas. Beyond its relevance as a geographical unit for water resources development and management purposes, the river basin is also a political and ideological construct, with its discursive representations and justifications, closely linked with shifting scalar configurations, both ecological and in terms of regulatory regime or governance. How interconnected and nested waterscapes can be managed by discontinuous nested political/administrative and social levels remains a fundamental question fuelling an endless search for elusive governance systems that would unite nature and society.

The goal of the project was to develop integrated and user-oriented strategies to safeguard public health concerns without compromising livelihoods and land and water productivity in wastewater irrigated urban and peri-urban vegetable farming. In this project, assessment of land and water productivity in wastewater irrigated farming was done, levels of contamination on irrigation water and vegetables quantified at different levels along the food chain (farms, markets and consumer level) and appropriate lowcost risk reduction strategies identified and participatory testing done with stakeholders at farm and consumer levels. A large number of students were involved in the project, significantly building human capacity.

The overarching goal of this paper was to determine how irrigated areas change with resolution (or scale) of imagery. Specific objectives investigated were to (a) map irrigated areas using four distinct spatial resolutions (or scales), (b) determine how irrigated areas change with resolutions, and (c) establish the causes of differences in resolution-based irrigated areas. The study was conducted in the very large Krishna River basin (India), which has a high degree of formal contiguous, and informal fragmented irrigated areas. The irrigated areas were mapped using satellite sensor data at four distinct resolutions: (a) NOAA AVHRR Pathfinder 10,000 m, (b) Terra MODIS 500 m, (c) Terra MODIS 250 m, and (d) Landsat ETM 30 m. The proportion of irrigated areas relative to Landsat 30 m derived irrigated areas (9.36 million hectares for the Krishna basin) were (a) 95 percent using MODIS 250 m, (b) 93 percent using MODIS 500 m, and (c) 86 percent using AVHRR 10,000 m. In this study, it was found that the precise location of the irrigated areas were better established using finer spatial resolution data. A strong relationship (R2 0.74 to 0.95) was observed between irrigated areas determined using various resolutions. This study proved the hypotheses that “the finer the spatial resolution of the sensor used, greater was the irrigated area derived,” since at finer spatial resolutions, fragmented areas are detected better. Accuracies and errors were established consistently for three classes (surface water irrigated, ground water/conjunctive use irrigated, and nonirrigated) across the four resolutions mentioned above. The results showed that the Landsat data provided significantly higher overall accuracies (84 percent) when compared to MODIS 500 m (77 percent), MODIS 250 m (79 percent), and AVHRR 10,000 m (63 percent).

This module is about water resources, their complex relationship with the environment and the economy and the growing problem of water scarcity and the various options that exist to deal with this problem. The module examines how water is allocated between various competing demands and explores the role that water plays in food security, public health, people’s livelihoods and other aspects of social and economic development. The module seeks to critically evaluate the benefits, costs and impacts of water resources development, particularly those aspects most relevant to social and economic development in rural areas. Coverage includes the key water management challenges communities are facing today and the solutions that people have developed. Parts of the module concentrate on the ways in which economic concepts, methods and judgements can inform water resource management strategies and policy decisions that affect the resource. Economic efficiency in resource allocation is only one of many criteria used by policy-makers to evaluate the appropriate approach to a given issue. However, the insights given by the application of economic theory are often ignored in the face of conflicts over the use of water. The module also introduces a range of techniques, methods and information resources that can be used by professionals for the assessment of water resources and planning. Good information and good applied science are keys to improved water resource management and should be considered as necessary but not sufficient. It is also vital to develop the institutional arrangements and policies necessary for sustainable water use and environmental conservation. Thus governance arrangements in relation to water management are also a leading theme of the module.