Performance evaluation of detached breakwaters for sustaining the coastline of Alappad

Coastal erosion is a major problem facing the coastlines of the world, which needs to be addressed with priority. Coastal properties and roads are threatened by erosion, particularly during the monsoon. Long lasting coastal protection is needed to solve the beach erosion problems. Breakwaters are effective in reducing the cross shore sediment transport and in wave height reduction in its lee. In the present study, the effectiveness of detached breakwater system for the protection of Alappad coast is done using the various modules available in the software package, MIKE 21. A coastal stretch of 3.5 km along shore and 6.5 km in the offshore direction is considered for the study. In the study, it is found that alongshore transport is predominant and the current direction is towards north in the study area. Submerged breakwaters proposed are aesthetic and are found to drastically reduce the wave heights during monsoon. Design and cost estimation of breakwaters have also been done.