Groundwater quality changes in the tsunami affected coastal belt - Southern Sri Lanka

The groundwater quality of an aquifer system in Mirissa area was studied. 19 dug wells distributed over a 6 km coastal strip were selected. The dug wells were sited in a line perpendicular to the coastline. Most of the dug wells were shallow and their diameter ranged from 0 to 1m. In low lying coastal areas, electrical conductivity was 3500 μs/cm. Heavy rains in early January improved the quality in coastal groundwater and hydro geological discharge was also significantly affected. First and second lines receiving their recharge from inland. Therefore, pH values changed and the quality of water significantly improved giving an electrical conductivity below 1000 μs/cm.