48. Groundwater-Seawater Interactions in Tsunami Affected Areas: Solutions and Applications

The December 2004 tsunami in the Indian Ocean caused a disaster affecting thousands of kilometers of coastal zone in SE Asia. Many coastal wetlands were affected in the short term by the large inflow of salt seawater and littoral sediment deposited during the tsunami, and in the longer-term by changes in their hydrogeology caused by changes to coastlines and damage to sea-defences. Many water quality and associated problems were generated by the tsunami. The tsunami has created an accelerating process of salt-water intrusion and freshwater contamination in the affected regions that now require drastic remediation measures. According to the International Commission on Groundwater-Seawater Interaction (CGSI) these measures have to be economically feasible, environmentally sound and socially acceptable. We report here some results of preparation of the CGSI EU FP7 project related to the study of the processes of groundwater-seawater interactions in tsunami affected areas.