Hydrological Viability Analysis for Minor Irrigation Tanks Cascade System using Remote Sensing and GIS

Many of the Andhra Pradesh minor irrigation tanks are inter-connected cascades, allowing surplus flow of the upstream tanks and return flow from the upstream command area to reach straight away downstream tank. To increase the irrigation supply in downstream of command area, irrigation tanks are being used. There are several troubles of the irrigation tanks, such as reduction of design discharge as a result of silting of channel and tanks, deterioration of stone masonry channel, and encroachment of drainage courses and tank water spread leads to the decline of tank performance. Water Resources Department (WRD) is implementing Andhra Pradesh Integrated Irrigation and Agriculture Transformation Project (APIIATP) for improvement and management of minor irrigation tanks through community based approach with the funding of World Bank. The prediction of water availability in tank is important for the purpose of improving productive use of the water resources in a tank cascade system. The land use/land cover map was prepared using LISS-IV imagery. The drainage courses problems are identified in the tank cascade system by SOI 1: 50,000 scale toposheet and satellite image. The problems were found in the earthen channel, catchments and head works. For the identified problems, the remedial measures are suggested for improving the tank cascade system to restore it to its original condition.