CHENNAI: As the shore along Arulmigu Subramaniya Swamy Temple in Tiruchendur, visited by millions of devotees throughout the year, is facing a threat of erosion, a protection wall made of polypropylene gabion boxes filled with granite has been proposed by IIT-M. The temple administration is seeking state coastal zone management authoritry’s clearance for the `19.80 crore project.
Sources said the Ocean Engineering Department of IIT-M has proposed a seawall to a length of 520 metres along the temple to safeguard the eastern side of the compound wall and existing structures close to the sea. Gabion boxes will be placed up to 20 m towards sea from the existing compound wall.
Gabion boxes are net enclosures woven by polypropylene rope and will be filled with stone boulders. The filled boxes will be placed along the existing sea wall in line and maintaining the design slope using a crane. The boxes will be placed without gaps between adjoining units.
However, the hitch is that the state has not prepared a shoreline management plan (SMP) as mandated by national green tribunal in its direction on April 11, 2022. It has directed that pending preparation or updation of such SMPs by coastal states or union territories, no hard structures for erosion control be raised or constructed. Since the proposed project is only repair and reconstruction, the NGT order may not be applicable for repairing the seawall, sources said.
The temple complex on the eastern side corridor has been witnessing erosion since 1960. The seawall was built by dumping stones in 1963 and it has been periodically repaired.Erosion over the last 60 years has advanced so much that the eastern side of the temple now falls close to the high tide line, a study done by HR& CE Department through Indomer Coastal Hydraulics said.
The report said natural calcareous/pearl/coral reefs, which existed during historical time at 1km distance offshore, were destroyed by illegal mining and the damaged reef is not offering much protection to the shore. During monsoon, these reefs are not able to attenuate high waves, which cause erosion. The report has recommended the reconstruction of damaged reefs by placing artificial reefs which will protect the shore, increase fish breeding and help coral/pearl growth.