Micro level hydrological planning and assessment of tank irrigation system

Abstract

Dependence of Groundwater is alarmingly increasing in Tamil Nadu due to irregular rainfall patterns and improper management of surface water systems particularly, the Ground Water resources overexploited in many blocks of Tamil Nadu for domestic and irrigation use leading to seawater intrusion, depletion of water tables and water quality degradation. This study is carried out for Kolur village of Ponneri taluk, Tiruvallur district, located near the sea coast where large number of tanks are available, yet agriculture practice depend solely on groundwater due to lack of maintenance of tanks and irrigation channels. UAV drone data in this study enables automatic Micro level mapping of waterways from tanks to the fields even at the field channel level where conventional remote sensing is unusable. The maximum storage capacity of the tank has been determined using the DEM created from the UAV data. At present, paddy is the dominant crop grown in study area with the help of groundwater. The volume of water stored in the tank as a result of the runoff generated from precipitation in the catchment area during the paddy season is calculated using HEC-HMS model. Water requirement during the paddy season in the study area is calculated using evapotranspiration derived from the MODIS-MOD16A2 data and Precipitation derived from the TRMM dataset. The present study shows that tank irrigation system can supplement efficient irrigation of paddy crops in the study area by proper maintenance of the channel system, thereby decreasing the excessive use of groundwater for irrigation purposes.