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.
