Application of Remote Sensing and Geographic Information System Techniques to Flood and Rainwater Harvesting: Case Study of Sennar, Sudan

Construction of the Grand Ethiopian Renaissance Dam will have positive and negative impacts on the people living downstream. Among possible impacts is the probability of flooding of human settlements along the Blue Nile. Reduction of water level is also a possible adverse effect of this dam on the agricultural schemes along the Blue Nile; the Gezira scheme, one of the largest irrigation projects in the world, could be affected by such reduction. The objective of this study is twofold. The first objective is to identify cities and villages near the Sennar Dam (in Sudan) that may be affected by potential fluvial (river) floods. The location of the study area near the dam exposes it to a probable dam problem and, consequently, societal, environmental, and economic damages. Therefore, identifying vulnerable locations is crucial for reducing risk to lives and properties, for preparing contingency action plans, and for making the area more resilient. The second objective is to select rainwater-harvesting (RWH) sites that can be used for water-supply backup while minimizing possible water-level reduction. The use of remote-sensing and Geographic Information System (GIS) techniques in this study has enabled access to unique sources of information to better characterize hazards and risks.