Simulated Impacts of Climate Change on Surface Water Yields over the Sondu Basin in Kenya

Potential impacts of climate change on surface water yields over the Sondu River basin in the western region of Kenya were analysed using the Soil and Water Assessment Tool (SWAT) model with climate input data obtained from the fourth generation coupled Ocean-Atmosphere European Community Hamburg Model (ECHAM4) using the Providing Regional Climates for Impacts Studies (PRECIS) model. Daily time step regional climate scenarios at a spatial grid resolution of 0.44Ëš over the Eastern Africa region were matched to the Sondu river basin and used to calibrate and validate the SWAT model.Analysis of historical and projected rainfall over the basin strongly indicated that the climate of the area will significantly change with wetter climates being experienced by 2030 and beyond. Projected monthly rainfall distribution shows increasing trends in the relatively dry DJF and SON seasons while showing decreasing trends in the relatively wet MAM and JJA seasons. Potential changes in water yields resulting from climate change were computed by comparing simulated yields under climate change scenarios with those simulated under baseline conditions. There was evidence of substantial increases in water yields ranging between 88% and 110% of the baseline yields by 2030 and 2050 respectively. Although simulated water yields are subject to further verification from observed values, this study has provided useful information about potential changes in water yields as a result of climate change over the Sondu River basin and in similar basins in this region

Synthesis 2006

The purpose of this report is to summarize and synthesize activities and achievements of the CPWF through the end of 2006. The CPWF is a CGIAR Challenge Program designed to take on the global challenge of water scarcity and food security. It takes the form of an international, multi-institutional research-for-development initiative that brings together scientists, development specialists, and river basin communities in Africa, Asia and Latin America. It seeks to create and disseminate international public goods (IPGs) helpful in achieving food security, reducing poverty, improving livelihoods, reducing agriculture–related pollution, and enhancing environmental security. This Challenge Program is a three-phase, 15-year endeavor. Several years have passed since the start of Phase 1 (2003-2008) which began with an inception phase in 2003 and was followed by full CPWF launch in January 2004. Research projects began field operations in mid-2004. This synthesis report, then, only describes work carried out in the first two and a half years of the Program. During this time, CPWF has conducted its research on water and food in nine benchmark basins, organized around five different themes. This work is being implemented through “first call projects”, “basin focal projects”, “small grant projects” and “synthesis research”. This present report is one example of the latter. CPWF projects have made considerable progress in developing innovative technologies, policies and institutions to address water and food issues. Some projects focused on improving agricultural water productivity. Others focused on developing mechanisms to inform multi-stakeholder dialogue and negotiation, or explored ways to value water used to produce ecosystem services. Advances were also made in understanding water-foodpoverty links, and their regional and global policy context

Challenges and prospects: agricultural water management from a river-basin perspective

In Jinendradasa, S. S. (Comp.). Issues of water management in agriculture:compilation of essays. Colombo, Sri Lanka: Comprehensive Assessment Secretaria

Managing the externalities of declining dry season river flow: a case study from the Ewaso Ngiro North River Basin, Kenya

Upstream-downstream water conflicts are common phenomenon in most basins. Such conflicts take a different dimension when they occur during dry season with an already low level of river flows. This context aggravates the spatial externalities on downstream communities and water-dependent ecosystems, causing serious socioeconomic and ecological effects. Utilizing an analytical framework to capture the causes and consequences of the spatial nature of these externalities and relying on both primary and secondary data pertaining to the Upper Ewaso Ngiro North basin in Kenya, this paper (1) shows how these externalities are caused more by upstream land and water use changes than by any climatic and hydrological factors, (2) evaluates the nature and magnitude of their impacts on different downstream community groups, (3) assesses the extent and success of past policy responses and local initiatives, and (4) concludes by indicating the needed approach and interventions for finding a durable solution to the problem of upstream-downstream water conflicts and externalities

Water scarcity and conflicts: a case study of the Upper Ewaso Ng'iro North Basin

In Blank, H. G.; Mutero, C. M.; Murray-Rust, H. (Eds.). The changing face of irrigation in Kenya: opportunities for anticipating changes in Eastern and Southern Africa. Colombo, Sri Lanka, IWM