Identification of potential sites for water harvesting structures using geospatial techniques and multi criteria decision analysis

Abstract

Changing hydrological phenomenon and increase the water demand in all sectors create a huge problem of water scarcity. Precipitation is one and only major source to mitigate this problem. In Central India, the average annual precipitation is sufficient in most of the part but not capable to harvest and utilize during the summer season. Identification of suitable site for water harvesting structures plays a key role to enhance the water level for watershed management. In the present study, suitable sites have been demarcated to build up a water resource development plan in Mandri river watershed of Kanker district, Chhattisgarh using Remote Sensing and GIS techniques. Basic guidelines of Integrated Mission for Sustainable Development (IMSD) have been used for identifying the suitable sites for water harvesting structures. Remote Sensing and GIS are used for site suitability analysis of water harvesting structure to extract the information of various features such as lineament, land use/land cover, soil, slope, lithology, geomorphology, drainage order, rainfall etc. In order of importance, we have assigned weights to each feature. Slope and design discharge are key parameters in site suitability analysis, so that we assigned maximum weight to this parameters. A possible site suitability map for water harvesting/conservation structures was derived following an Analytical Hierarchy Process (AHP) and Multi-Criteria Decision Analysis (MCDA). This work attempts to identify the probable zone for water harvesting structures such as boulder check/gabion, gully plug/bori bandhan, check dams and stop dams. Multi-criteria analysis is applied in GIS to assist the decision-makers in determining appropriate zones for water harvesting structures in view of external characteristics of the watershed. Further, using weighted overlay method, the catchment was grouped into categories of suitable or highly suitable.