Tamil Nadu uses artificial reefs, corals and seagrass to save shrinking Kariyachalli island
29 September 2026
Kariyachalli, one of 21 islands in the Gulf of Mannar, has shrunk from 20.85 hectares in 1969 to 3.14 hectares in 2025. It could vanish by 2036 without intervention. Tamil Nadu is deploying about 8,500 artificial reef modules and restoring coral and seagrass meadows. The reefs and seagrass dampen wave energy and help hold the shoreline. Tamil Nadu's Department of Environment, Climate Change and Forests, IIT Madras and the Suganthi Devadason Marine Research Institute are involved.
In plain words
Artificial reef Man-made underwater structure — A built structure placed on the seabed to host corals and fish and to break waves.
Seagrass Flowering marine plants — Underwater meadows that trap sediment and shelter marine life.