Subscribe
Recently, scientists at the Center for Study of Science, Technology and Policy, Bengaluru, published a research paper which predicted that 5 per cent of the land in coastal Karnataka’s Mangaluru and Udupi could get submerged by the year 2040. However, other scientists that Down To Earth (DTE) spoke to said the findings should not be sensationalised.
Coastal erosion is not as dangerous as it is purported to be, according to marine geologists from various organisations like the National Institute of Oceanography (NIO) in Goa and Mangaluru University’s Department of Marine Geology.
It is a very long-drawn process that might not be felt for generations. It is highly unlikely to be erratic and sudden, they add.
“The rise in the sea level is unstoppable, but the submergence of cities was exaggerated,” R Shankar, former head of the Department of Marine Geology at Mangaluru University, who is also acknowledged among the top marine geologists of the country, told DTE.
“There could be two reasons for the rise in the sea level: natural and anthropogenic. While not much could be done for natural reasons, the anthropogenic reasons could be minimised or even fully mitigated. The best is to stop doing construction activities on and near the coastline. And move away from the coast, allowing Mother Nature enough space to play,” he added.
While Karnataka’s coastline has not been officially assessed, it has seen lakhs of rupees being spent on the ineffective practice of dumping boulders along its shores. This annual ritual, repeated every monsoon, has failed to stop erosion and may even exacerbate it by disrupting the natural flow of sand along the coast.
According to marine geologists at NIO, sand removed by the sea is typically returned to the same location before the next monsoon, a process hindered by artificial barriers.
Despite the evidence, various interest groups continue to promote invasive solutions like permanent sea walls and boulder dumping, drawing inspiration from models used in France, New Zealand, and Australia.
Experts from Mangaluru University, NIO, and ICMAM strongly oppose these measures, arguing that human-made coastal structures are both invasive and costly, with limited effectiveness.
These structures often fail to withstand the sea’s power, leaving those who benefit from government compensation in the same vulnerable positions year after year.
The National Institute of Technology Karnataka (NITK) offers a more sustainable approach in its manual on coastal erosion. The institute advocates for a strategy of retreat, acknowledging that the sea’s advance and retreat are natural, cyclical processes observed worldwide.
Millions of years ago, the Arabian Sea reached the Western Ghats but has since receded to its current position. Human settlements must adapt to these changes by retreating from vulnerable areas, a principle that aligns with the core values of the coastal regulation zone (CRZ) regulations.
SG Mayya, former head of the Department of Applied Mechanics at NITK, stresses the need for a long-term policy that discourages development near the High Tide Line and promotes the relocation of human settlements.
“No human-made structure can permanently protect the coast,” he said. “The only sustainable solution is to respect the natural dynamics of the sea and keep human habitation away from vulnerable areas.”
Local fishers, who have lived in harmony with the sea for generations, understand its power better than anyone. They wisely avoid building their homes close to the shore, mocking those who do.
This practice reflects a deep respect for the sea, something that government policies have failed to embrace. Instead, the government continues to spend vast sums on boulder dumping, a practice that senior residents like Tanveer Hasan of Kotepura in Mangaluru taluk criticise as a ‘wasteful misuse of public funds’.
Coastal erosion is a natural phenomenon observed in several locations along Karnataka’s coast, including Kotepura, Padukere near Udupi, Rabindranath Tagore Beach in Karwar, and Ganesh Bagh Beach in Ankola.
Despite spending over Rs 20 crore over the past 25 years, the state government is now considering a further investment of Rs 990 crore in constructing sea walls along various stretches of the 40-kilometre-long coastline.
However, civic activists in Ullal, about 10 kilometres from Mangaluru city, argue that this money would be better spent on building a safe, well-equipped township away from the coast, out of the reaches of the CRZ, ensuring the safety of residents during the monsoon.
Engineers from the Minor Irrigation Department have advised against allowing any human habitation on vulnerable stretches like Kotepura, as well as all other places like Udyavara in Udupi taluk, Kodi Bengre in Kundapur taluk, Mazhali in Uttara Kannada, Canacona, and Porvorim in Goa. But their warnings have been overshadowed by political interests. As a result, illegal constructions continue to proliferate, exacerbating the problem.