Posted on July 20, 2022
For someone who grew up in a small town in Dakshina Kannada and spent several years in the coastal town of Mangaluru, a visit this year during the monsoon season did not go as planned. Incessant rains led to flooding in several cities in Dakshina Kannada and Udupi districts, with the respective administrations even shutting down schools and colleges. In the last couple of years, another major problem is plaguing Karnataka’s coastline, especially during monsoon season – i.e. sea erosion at a rapid pace.
Even in the current monsoon season, rapid coastal erosion was seen in several areas of Udupi and Dakshina Kannada districts.
The problems of coastal Karnataka finally reached the power corridors of the capital Bengaluru, triggering a visit from Chief Minister Basavaraj Bommai, who promised to “implement new technologies to check sea erosion and discuss long-term as well as short-term measures”.
The chief minister also said a Permanent Solution Committee would be set up to find a solution.
What is coastal erosion?
Simply put, coastal erosion is the loss of coastal land, in which sediments and bedrock of the shoreline are removed due to the strong action of waves and currents. While it occurs naturally, human activities like excessive sand mining and illegal constructions in Coastal Regulation Zones (CRZ) can accelerate the process.
According to Kolkata-based senior climatologist Kailash Pandey, a rise in sea level can also cause coastal erosion.
“Sea level rise can increase coastal erosion because waves can extend further up and along the beaches. The rise in sea level is due to global warming,” Pandey told News9.
Karnataka has a coastline of nearly 313 kilometres and every year sea erosion is accelerating.
According to a status report by the Ministry of Earth Science’s National Centre for Coastal Research, 22 per cent of Karnataka’s coast is eroding, while 48 per cent was in a stable state.
The findings were based on a shoreline analysis between 1990-2016.
It was also observed that 45 per cent of Dakshina Kannada is “relatively affected by erosion”.
Another research paper in 2019 noted that between 1990-2016, there was severe erosion in Ullal, which had lost land at 1.3 metres per year.
“Both anthropogenic activities like ports, seawalls, breakwaters, etc and natural processes like longshore drift, seasonal variation, etc are factors affecting the shoreline change along the Karnataka coast,” noted the paper.
A recent analysis noted that due to the rise in sea level, key infrastructure in many coastal cities including Mangalore might submerge.
Challenge lies in finding a solution
As soon as the recent incidents of coastal erosion and damage caused by rains made the headlines, the state government sprung into action, announcing relief. Chief Minister Bommai also, interestingly, said the state is mulling over using sea wave breaker technology.
Ullal will host the pilot project and based on the results “a permanent scheme will be implemented”.
Speaking to News9, UK Yoosuf, an industrialist based in Kerala’s Kasaragod and the chairman of the company that manufactures the sea wave breakers, said that his technology is resistant to waves.
“Large boulders placed on the sand are not resistant to strong waves. However, to implement our technology, we use a large block, which weighs around 400 tonnes. The block is 50 feet in length, 20 feet wide and 15 feet in height. Not even an earthquake and a Tsunami can rattle it,” said Yoosuf.
He added that the cost is also approximately 10 per cent of the other technologies that were used earlier.
“I have kept the cost low so that we can find a lasting solution to this problem. Making money through this project is not my aim and hence I have kept the cost to the minimum,” said the industrialist.
Boulders and tetrapods, Yoosuf explained, which are placed on the sand are an easy task for the waves to dismantle.
“However, the blocks that we use are dug and fixed in the sand and not just placed on it. Hence, it won’t be affected by stronger waves,” claimed Yoosuf.
He added the installation cost of the project will be approximately Rs 24 crores, along with the garden, road and lighting.
For the sceptics, Yoosuf has an answer as he has already tasted a small victory in Kasargod’s Nellikunnu, where his technology was used and received a positive response.
Here’s a video showing how the sea wave breaker works:
Crores spent, results unachieved
So far, crores of rupees have been spent by the state government to find a solution to the problem of coastal erosion.
Chief Minister Bommai, acknowledging the problem, said that although Karnataka had spent nearly Rs 300 under the Asian Development Bank (ADB) project, the results were not satisfactory.
According to Daijiworld.com, a Mangaluru-based news portal, the work under the ADB project has been continuing since 2010. But, so far, not much has changed in terms of stopping accelerating erosion.
Locals in the area, the report noted, say that the solution does not lie in placing boulders on the beach.
“They are of the opinion that corrective measures need to be taken after studying the wave pattern of the sea at particular zones,” noted the report.
The way ahead
Climatologist Pandey listed some ways in which coastal erosion can be controlled: through sea walls, installing geosynthetic tubes, and growing more vegetation along the coastline.
Sea walls are just soft solutions, Pandey explained, while the other two mentioned above are hard stabilisation solutions.
“Existing methods like seawalls and sand bypassing systems are conventional and are rather expensive,” said Pandey, adding that India should also take a cue from other countries that have found solutions.
The climatologist also laid an emphasis on training engineers who work in these places and take the help of locals, who are the real stakeholders.
“More awareness towards coastal systems and their ecology needs to be created to the public,” stressed Pandey.
Some of the long-term solutions that Pandey mentioned include the use of flexible or rigid gabions, chain of blocks and concrete pipes.
A recent study conducted by the University of Kerala recommended using “artificial reef implantation inside the sea and installing floating steel structures to break the waves”.