Coastal Erosion in Karnataka: Science vs. Sensationalism

A recent study by the Center for Study of Science, Technology, and Policy in Bengaluru has predicted that 5% of Mangaluru and Udupi’s coastal land could be submerged by 2040. However, marine geologists from institutions like the National Institute of Oceanography (NIO) and Mangaluru University caution against sensationalising these findings. They argue that coastal erosion is a slow, natural process that is unlikely to result in the abrupt submersion of cities. R. Shankar, a renowned marine geologist and former head of the Department of Marine Geology at Mangaluru University, acknowledges the inevitability of sea level rise but believes the threat has been overstated. He attributes sea level rise to both natural and human-induced factors and suggests that mitigating human impact, such as halting coastal construction, could minimize damage.

Despite the lack of an official assessment of Karnataka’s coastline, significant funds have been spent on ineffective erosion control measures like boulder dumping. This practice, repeated annually during the monsoon, disrupts the natural flow of sand and may worsen erosion. Marine geologists at NIO explain that the sand removed by the sea is usually returned to the same location before the next monsoon, but artificial barriers interfere with this natural process.

Invasive solutions like permanent sea walls and boulder dumping continue to be promoted by various interest groups, inspired by models from countries like France, New Zealand, and Australia. However, experts from Mangaluru University, NIO, and ICMAM argue that these structures are costly, invasive, and often fail to withstand the sea’s power, leaving coastal communities vulnerable.

The National Institute of Technology Karnataka (NITK) proposes a more sustainable approach to coastal erosion in its manual, advocating for a strategy of retreat. The institute emphasizes that the sea’s advance and retreat are natural, cyclical processes observed worldwide. Millions of years ago, the Arabian Sea extended to the Western Ghats but has since receded. Human settlements, according to NITK, should adapt by relocating from vulnerable areas, in line with Coastal Regulation Zone (CRZ) regulations.

SG Mayya, former head of NITK’s Department of Applied Mechanics, underscores the importance of a long-term policy that discourages development near the High Tide Line and promotes the relocation of human settlements. He insists that no human-made structure can permanently protect the coast and that the only sustainable solution is to respect the sea’s natural dynamics.

Local fishers, who have lived in harmony with the sea for generations, avoid building homes close to the shore. They criticize the government’s continued investment in boulder dumping, with senior residents like Tanveer Hasan from Kotepura in Mangaluru taluk condemning it as a wasteful misuse of public funds. Civic activists in Ullal suggest that the money would be better spent on building safe townships away from the coast, beyond the reach of CRZ regulations.

Engineers from the Minor Irrigation Department also advise against allowing human habitation on vulnerable stretches of the coast, but their warnings are often ignored due to political interests, leading to the proliferation of illegal constructions that exacerbate the problem.

Read More:

Coastal Erosion Devastates Mangalore Residents During Monsoon

Bengaluru Scientists Warn of Rising Sea Levels: Coastal Karnataka at Risk