Evaluation of Beach Volume Along the Tsunami Affected Coast, Southern East Coast of India

To comprehend the impact of 26 December 2004 tsunami on beach environment, an assessment of the beach sediment volume in respective zones of the beach profile has been done by comparing the pre-event and post-event beach profile data. In spite of the considerable accretion in some of the beaches, rest of the beaches had suffered erosion. The coastal configuration, bathymetry, component of the beach, etc. had played a key role in determining the extent of change in the beach sediment volume. Erosion had occurred mostly in dune and berm while littoral zone favoured accretion of sediments eroded from the dune, berm and also the ‘fresh’ se diments brought in by the tsunami surge from the continental shelf. River inlets and other water passages had greatly influenced the degree of erosion by facilitating the seismic waves to inundate much of the coastal zone. The degree of erosion ranges between 1.84 m3 and 0.34 m3 with a maximum at Manappad and with a maximum at Periyathalai, the accretion amount varies from 1 .36 m3 to 0.06 m3. Apart from Manappad, Kulasekaranpattinam, Alanthalai and Kayalpattinam, Tuticorin-2 was the heavily eroded beach whereas the beaches like Periyathalai, Tiruchendur and Veerapandianpatinam had the benefit of accretion. Erosion and accretion had played one and the same in the beach of Tuticorin-1.