It is a very important subject for the preservation as well as for the utilization of the groundwater to maintain sound water circulation to evaluate the role of the groundwater pumping for irrigation and the recharge through paddy fields. As case study, we selected the national irrigation project site. First we made a tank-modal to simulate present groundwater balance in the site. Based on the calibrated model, simulation was carried out for water-balance and water level fluctuation in two cases:
·Recharge through paddy fields is terminated.
·Pumping up is terminated.
The analysis showed that the model evaluated the role of pumping up as well as of recharge through paddy fields in the water balance.