APPLICATION OF GIS AND MCE TECHNIQUES FOR OPTIMUM SITE SELECTION FOR WATER HARVESTING STRUCTURES

Abstract

Water is a primary necessity for the sustainable survival of all forms of life and enormously scarce in arid parts of the world including India. The basic unit of water resources assessment and planning is a watershed. Water resources management at a watershed scale requires both water supply and demand management which includes water conservation through rainwater harvesting, groundwater recharge, and recycling. The present study is aimed to assess the potential of water harvesting and to identify suitable sites for water harvesting structures in Kolayat watershed of Bikaner district in Rajasthan by using Geographic Information System (GIS) and Multi-Criteria Evaluation (MCE). Proposed methodology of water harvesting site selection has compared with traditional methods of site selection. In traditional practices, the location of the structure is selected by visiting the geographical areas and looking at the various drainage patterns, soil erosion, land use land cover, water storage areas, availability of insects/ animals, native population feedback and past experiences. These practices are entirely dependent on instincts and results of the selected zones are uncertain. However, geospatial analysis techniques like RS, GIS, and MCE are the innovative tools which can be used to determine suitable sites for rainwater harvesting structures based on the watershed characteristics. The soil conservation service model (NRCS curve number) has been used to estimate the runoff. Further, spatial analysis in GIS has been carried out considering MCE along with the Analytical Hierarchy Processes (AHP) to assess the water harvesting potential and to identify the optimum locations of rainwater harvesting structures.