Search is on for a substitute for sea wall

With the South West monsoon just weeks away, hundreds of fishermen and their families are bracing themselves to face the fury of the sea, even as large stretches of the coast remain vulnerable to heavy erosion in the absence of an integrated, scientifically designed protection strategy.

The present strategy, weighing heavily in favour of the construction of sea walls, has come in for widespread criticism from fishermen and scientists who feel that it is dictated by a section of corrupt government officials acting in collusion with contractors.

Demanding a review of the strategy, fishermen stressed the need for an alternative approach in view of the huge investment in building sea walls and the recurring expenditure in maintaining them. Scientists point out that a sea wall hinders sediment travel, leading to accelerated erosion on the leeward side. It is the last option in beach protection and a costly proposition.

Studies have shown that construction of sea walls had affected the hydrodynamics of the Kerala coast, causing mass migration of several species of fish. It is also blamed for the decline in shore-based fishing activities.

According to N.P. Kurian, director, Centre for Earth Science Studies, the best coastal protection strategy is to preserve the beach by distancing all developmental activities and creating a buffer zone for the interplay of land and sea. He says that the best option for Kerala will be to relocate the coastal population to safer ground ahead of the monsoon when erosion takes place.

Dr. Kurian feels that coastal protection measures should be preceded by site-specific studies. “Shore-based protection methods such as construction of sea walls work well only for wide beaches. Features such as artificial reefs and submerged breakwaters are a better option for narrow beaches. Construction of groynes and beach nourishment are other alternatives that can be deployed based on site studies.”

T. Peter, vice-president, National Fishworkers’ Forum (NFF), blames the unscientific design and construction of sea walls and harbours for the heavy erosion along the coast. “Rehabilitating families from the vulnerable stretches of the coast will cost only a third of the investment on construction and maintaining sea walls. Yet, the nexus between officials and contractors ensures that sea walls get preference.”

Mr. Peter says the uncontrolled extraction of sand from river beds, lakes and estuaries had reduced the upstream sediment supply, depleting the quantum of beach sand. Beach sand-mining itself compounds the problem, exposing more areas to the ravages of the sea, he observes.

Unscientific construction of sea walls criticised

Plea for integrated approach to coastal protection

Recommended for you