Only 10 per cent of TN coastline is stable, says study

Chennai:

Tamil Nadu’s coastal land mass may have increased by 25.45km but the
state has less to cheer about and more to be concerned as only 10 per
cent of the entire state’s coastal area is a stable one.



The shoreline of Tamil Nadu coast is undergoing change and it has
increased by about 25.45 km due to accretion, according to a study
conducted by Indian Space Research Organisation and Central Water
Commission of Ministry of Water Resources.



The study states that the percentage of accretion coastline is highest
for Tamil Nadu which is around 62.3 per cent of the total shoreline
when compared to other coastal states. The study states that the cause
of high accretion is due to the Indian Ocean tsunami of 2004.



Due to it, the Andaman Coast suffered huge erosion, while there was
accretion along the Tamil Nadu coast, the study stated.



Interestingly, the state should be more alarmed about the increased
landmass across the coastline as the study also points out that the
state has less than 10 per cent of stable coastline.



R Ramesh, director of Chennai-based National Center for Sustainable
Coastal Management, an autonomous body of Ministry of Environment and
Forest, told Express that the lack of stable coastline is a matter of
concern.



He said there is need to prepare a strategy to strike a right balance
before coming up with structures along the coast. “The hydrodynamics
need to be studied besides we have to analyse which all projects is
compatible along the coast,” he said.



He said the gaining of land mass due to accretion need to be studied.
“We have to find out which parts of the coast, the accretion is
happening and which part erosion is happening,” he said.



Interestingly, the satellite data for detection of violation of land
use along the Coastal Regulation Zone and Impact of Port Structures on
Shoreline changes by Indian National Centre for Ocean Information
Services (INCOIS) and Ministry of Earth Sciences which has been
submitted to Union Ministry of Environment and Forest states the three
ports--- Chennai Port, Ennore and Katpuli has affected the shoreline.



While the North Chennai shoreline recessed by about 1,000 metres in
the last 125 years, the south Chennai gained more land mass.



Ramesh agrees with it. He says that this is due to the construction of
breakwaters in Ennore and Katpulli, which has arrested the movement of
longshore sediment transport resulting accretion in south Chennai and
erosion in north Chennai.



Interestingly, the study by Space Applications Centre of ISRO and CWC
also highlights that the state along with Puducherry has lost 281.56
km due to erosion.



The study is also quite alarming as only 1,580km of the total 8,414km
of coastline (excluding the mouths of estuary, rivers and creeks) is a
stable coastline.

The study states that the Indian coast has lost a landmass of 73
square km during the period from 1989-91 to 2004-06 timeframe.



Factfile:

Tamil Nadu:

Total length: 824.93 km (excludes moth of rivers, streams, creeks and
their inner parts)

Coastal erosion: 281.56

Accretion length: 514.11km

Stable length: 29.25km