Abstract:
More than two thirds of the coastline of Sri Lanka was subjected to inundation by the
Indian ocean tsunami on 26 December 2004. The inundation distance and the associated
damage caused by the tsunami varied widely with the local near shore wave height,
topography and the hydraulic resistance offered to the overland flow. In addition to the
ground surface resistance, the resistance offered by vegetation and man made features in
the coastal zone are among the contributory factors to the hydraulic resistance. It is
important to asses the resistance offered by coastal vegetation to the overland flow in
order to identify its effectiveness as a tsunami impact mitigation measure. Such a measure
would also have the duel advantages of being environmentally friendly and cost effective.