Nature of Seawater Intrusion in Jodiya and Dhrol Taluka by using GALDIT Method

This study presents the application of GALDIT method to evaluate the ground water vulnerability due to seawater intrusion in the Jodiya and Dhrol region of the saurashtra coast line. In 2001, Chachadi and Lobo-ferreria, developed the GALDIT method. Later in 2005, they modified the method specifically for coastal aquifers. Here the GALDIT index is used for the ground water vulnerability to sea water intrusion. The GALDIT index is based on four intrinsic hydro geological parameters, one spatial parameter and one boundary parameter. The parameters of GALDIT index are: ground water Occurrence (aquifer type), Aquifer hydraulic conductivity, High ground water level above the sea level, distance from the shore, impact of existing status of sea water intrusion in the area, and thickness of the aquifer GALDIT index is calculated after deciding the weightage, range and rate of each factor. The maps obtained using GALDIT method indicates that the aquifer system of Jodiya and Dhrol tehsil was low to medium vulnerable to seawater intrusion. GALDIT index of Jodiya tehsil villages were higher than Dhrol tehsil villages. Jodiya region is more vulnerable to seawater intrusion as compared to Dhrol region.