Model Assisted Planning of Agricultural Groundwater Development in Bist Doab Interbasin (India)

Present study aims at planning of agricultural groundwater development in Bist interbasin (India) that is experiencing excessive water table decline due to intense agricultural groundwater pumping. The interbasin covering an area of 8040 Km² comprises an alluvial unconfined aquifer that is hydraulically connected to two major perennial rivers viz., Satluj and Beas.  A finite difference based distributed flow model of the study area was calibrated for transmissivity geostatistically on the basis of discrete point data at 15 points, and head fields available at 6 discrete times. The deficit of transmissivity data was overcome by invoking the Pilot point approach wherein transmissivity at additional artificial points are estimated by the least squares approach. The calibrated model was oriented towards the agricultural objective by correlating its sink term with crop areas. The model was used to simulate the long-term stabilized head and the depth fields corresponding to prevailing cropping pattern. The simulation indicates large and unsustainable water table decline. The impact of various moderated cropping patterns on the water table decline was subsequently simulated. It was concluded that replacement of some fraction of area under water intensive rice crop by maize crop area may stabilize the water table depths to acceptable limit.