Groundwater Flow Modeling Of Vattigudipadu Watershed, Krishna District, Andhra Pradesh, India

摘要

Vattigudipadu watershed is in Agiripalli Mandal covering an area of 11.25 km~2. The area is formed with Gollapalli Sandstones and situated near Nuzvid, Krishna district, Andhra Pradesh, India. Ground Water Department, Government of Andhra Pradesh measured daily rainfall, pan evaporation and number of observation wells was monitored for water levels at Vattigudipadu Hydrometeorological station. The ground water flow model was constructed using Visual MODFLOW. The study area is divided into block centered finite grid of squares. The ground water flow system was simulated as two-layered aquifer system. The water levels of June 1982 are considered for steady state condition. The water table was computed at all node points. The computed values of water table were compared with those of the observed in the field. The initial values of recharge and permeability used in the model were adjusted to obtain a reasonable match of computed and observed water levels at observation wells during the process of calibration. The same model has been used for transient calibration from June 1982 to June 1992 by dividing the time period of simulation into 63 stress periods. The well hydrograph of the most of the observation wells are found matching closely with the computed hydrograph in the Transient state. From Water balancing in steady state the recharge, outflow and draft were of 5.39m.c.m, 0.53m.c.m and 4.86m.c.m (million cubic meter) respectively. From the transient state condition it is observed that there will be decrease in ground water storage, as there was a continuous exploitation of ground water.