Since 2007, IIT-Madras has reclaimed around 50km of lost beaches on Kerala's coastline by applying modern scientific technology to age-old 'Groin Fields' process.
Through the project, implemented following a request from the Kerala government to check erosion, 25 eroded sites of two km each around 25 villages were reclaimed.
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According to Prof V Sundar of department ocean engineering in IIT-M, who headed the project, a team from the department worked around Groin Fields, a technology which was last used in 1960s in India, and stopped erosion in around 25 coastal villages.
"After the tsunami, the Kerala government wanted a master plan for 25 villages to check erosion on stretches of two km in each. After investigation, we proposed 'Groin Fields' which yielded positive results. It has succeeded in retaining sand and building of the beaches. Thus, we reclaimed the lost beaches," said Sundar.
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Groin Field as one of the coastal protection measures had been tried successfully all over the world. It was used in India in 1960s and was "completely forgotten".
It was not a new idea from IIT-M, but the department "carefully designed with scientific process" to make a difference, said Sundar. Through this innovation, erosion activities didn't shift to nearby areas as feared earlier. Groin Field is a long, narrow structure built out into the water from a beach to prevent erosion.
What makes the concept of 'Groin Fields' unique is that it can actually recover land lost to the sea, unlike sea walls which can only prevent further erosion. However, Groin Fields require very precise calculations like quantity of sediments and direction of long-shore currents.
The team is currently implementing a 'Groin Field' technology project in North Chennai, south of Pulicat backwaters where a beach of the width of about 300 metres over a stretch of 3 km has been lost due to erosion. The first phase is to be completed in around a week's time.
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"IIT-Madras formulated a comprehensive shoreline management plan that was submitted to the Tamil Nadu government in 2015-16, suggesting solutions to coastal problems. Consequently, the IIT-M team is currently implementing a Groin Field Project in North Chennai," said Sundar.
On the eve of the World Ocean Day, the head of the project said just because India has a long coastline there is no place for complacency as there is an urgent need to conserve beaches and their socio-economic aspects. "Conserving the coastline has national and global implications," said Sundar.
The IIT-M team has also undertaken 'river mouth training' as a solution to choking of river mouths so that it flows freely into the sea. "A critical phenomenon observed at places like Kozhikode and Ettikkulam among others along the Kerala coast is the choking of river mouths due to longshore drifts. Construction of training walls, at the mouth of the river, ensured that the river will drain freely into the sea," he said.