Hydraulic Model Studies for the Design of Submerged Offshore Reefs for the Coastal Protection Measures

Coastal erosion is recession of the shoreline and loss of land area due to action of waves, currents and wind. In order to mitigate coastal erosion, submerged reef is one of the alternatives coastal protection measures provided to reduce the wave energy. Site specific coastal protections in the form of alternative cross-sections of submerged reefs have been evolved at the varying tidal range of micro to macro along the Indian Coast. The wave flume tests were conducted to ensure the hydraulic stability of different alternative cross-section of submerged reefs to withstand the design wave conditions. In order to hold the nourished sand, a series of submerged offshore reefs with sand-filled Geo-textile tubes have also been proposed at different sites. The submerged offshore reefs with sand-filled Geo-textile tubes have been provided and are performing well. The design of submerged offshore reefs through wave flume studies for the hydraulic stability and wave transmission has been discussed in this paper.