Identification of rainwater harvesting sites using RS and GIS for Mann river in Maharashtra

The soil and water are the prime input in crop production and serving as a continuous necessity for human survival. Therefore, it is imperative to assess and manage these resources in-situ to promote sustainable development on a watershed basis. Identification of suitable sites for rainwater harvesting (RWH) structures was carried out by weighted overlaying of the thematic layers. The weights assigned to slope, land use/land cover (LU/LC), soil, and rainfall are 33, 28, 21 and 18%, respectively. All the thematic layers were prepared in the geographic information system (GIS) environment in the raster format. Thematic layers (maps) were incorporated through rank / level by using Integrated Mission Sustainable Development (IMSD) guidelines. In this study, five thematic input layers of slope, LU/LC, hydrologic soil groups (HSG), drainage and rainfall were overlaid through weighted overlay for identifying the suitable sites for RWH structures in the Mann river catchment. A RWH suitability map with four classes was prepared for the watershed. The composite layer obtained from multiplication of the layer's weightage was averaged into four classes of highly suitable, suitable, moderately suitable, and poorly suitable. The suitable land for recharge facility creation like check dams, percolation ponds, continuous contour trench (CCT) and farm ponds were assigned to study area. The study area is having the full scope for the farm ponds, checks dams, percolation tank, and CCT. According to the IMSD guidelines 226 check dam, 11 percolation pond, 2075 farm pond and 8 CCT RWH structures site were identified. The estimated runoff volume could be stored at harvesting structures is 47554.40 ham that can be used for irrigation of agricultural / horticultural crops which would increase economy of the watershed.