Damage mechanism of Hikkaduwa due to December 2004 Indian Ocean tsunami

Abstract

More than two thirds of the Sri Lankan coastline got affected from the December 2004 Indian Ocean Tsunami. Field surveys conducted clearly indicate that some of the cities in the western coast of Sri Lanka in the shadow of the incident tsunami experienced significantly high damage similar to that of the eastern coast which was directly facing the incident tsunami. Destruction caused by the tsunami in the western coast was patchy and the cities like Galle and Hikkaduwa could be identified as the worst affected. In the case of Galle, the Bay and Headland combination would have increased the height and speed of the Tsunami wave and the damages accordingly. Even without such prominent coastal features Hikkaduwa experienced a similar scale of damages. This led to the investigations in identifying the damage mechanisms of Hikkaduwa where inundation and wave heights were as much as 5-10 times of the surrounding areas of the south west coast. Such complex mechanism of damages can be interpreted via results of Numerical Modeling and analysis of the existing coastal features in Hikkaduwa.