Performance evaluation of an irrigation command area using remote sensing: a case study of Mahi command, Gujarat, India

Multi-temporal remote sensing (RS) data-based crop inventory, generation of vegetation spectral index profiles and crop evapotranspiration estimation were carried out over the Mahi Right Bank Canal (MHRC) command (212,000 ha) in Gujarat, India, using Indian Remote Sensing Satellite (IRS)-1C Linear Imaging and Self Scanning-III (LISS-III) and Wide Field Sensor (WiFS) data. Distributary-wise, three RS-based performance indices, namely, adequacy (AI), equity (EI) and water use efficiency(WUE) were computed. AI was computed by comparing the crop water requirement with the water release data. EI was evaluated by observing the head-to-tail difference in two distributaries. It was found that water availabilty was in excess along main canals and branch canals. In cropped area, it was less and crop condition was poor towards the tail ends of the command area. WUE was computed as the ratio between the area under the vegetation index profile and the water applied. The three RS-based indices could rank the performance of the distributaries and also identify those having problems in water allocation and utilization.