Identification of cascade systems and assessment of the performance of village tanks at Madukanda agrarian service centre

Abstract

The objective of the study was to identify the cascades in the village tanks and to assess the performance of the tanks in the cascades. ArcGIS 10.2.2 and QGIS 2.8.2 software platforms were used to identify the cascades among the minor irrigation tanks in Madukanda Agrarian Service Centre in 2017. The study identified that there were 4 tank cascades consisting of 48 tanks with each of 15, 11, 6 and 16 village tanks in Madukanda area and twelve isolated tanks. The remaining 5 tanks were at the boundary of the study area. Among those 60 tanks in working condition, 44 tanks were randomly selected to assess the performance of village tanks. Cropping intensity and hydrological endowment were used to assess the performance of the tanks. Results revealed that 64% of the tanks were with good hydrological endowment whereas 36% of the tanks were with poor hydrological endowment. The average tank density was one tank per 2.68km2 in the study area. The average yield under village tanks, good hydrological endowed tanks and under poor hydrological endowed tanks were 4456 kg/ha (0.44 kg/m2) 4260 kg/ha (0.42 kg/m2) and 2880 kg/ha (0.28 kg/m2) respectively. The average cropping intensity and average yield of good and poor hydrological endowed tanks was statistically tested using ttest and found to be significant. Nearly 78% of the good hydrological endowed tanks had the cropping intensity of greater than one. Identification of the cascades would be useful to carry out rehabilitation activities which are essential to improve the tank performance in this district where tanks are the main source of water for irrigation.