Analysis of Groundwater Flow for Saltwater Interaction Range Using Visual Modflow: A Case Study of Coastal Belt in Srikakulam District of Andhra Pradesh, India

Groundwater flow modeling is one of the important tools to know the direction and magnitude of groundwater flow along the coastal aquifer. A study carried out in the coastal belt of Srikakulam showed a region where there is a probable mixing of ground water with the sea water. In the present investigation, the ground water flow and velocity are determined by using ModFlow Software. The entire study area has been divided into small grids. The wells are identified and located in eight lines perpendicular to the coastal belt. In this investigation, 97 existing wells are selected for carrying out the study. The distribution of the hydraulic head was estimated through a 20-year simulation. The observed results indicate that a considerable advance in seawater intrusion can be expected in the coastal aquifer of the study area. It is concluded that the average velocity of ground water in the Srikakulam coastal belt is 1.1 m/day. The results help to determine the groundwater flow channels and also help to explain the ground water recharge and flow areas in the aquifer.
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