TRENDS IN THE QUALITY OF GROUNDWATER IN BAHRAIN WITH RESPECT TO SALINITY, 1941-1992

This study presents trends in the quality of groundwater in Bahrain wi th respect to salinity during the period from 1941 through 1992. The r esults demonstrate that the salinity of groundwater is generally eleva ted above 2 g/L. Beginning with 1960, the quality declined. Seawater i ntrusion in the aquifers occurred mainly in the eastern region, where TDS values reached over 20 g/L, and saline water upflow occurred mainl y in the north central area. In the period from 1986 to 1992, about 33 % of the well water showed a TDS content greater than 4 g/L. Relativel y, the best-quality water was found in the northwestern areas where th e aquifer is directly recharged from Saudi Arabia by underflow. This i nvestigation presents a typical case study showing the impact of overe xploitation on the quality of groundwater.