Pallikaranai marsh in this metropolis is a treasure trove for biodiversity as it is home to nearly 700 species of various floral and faunal groups, including birds, plants, reptiles, and fish.
Much of this marshland has already been encroached by the state and central governments for housing institutes – its area has shrunk from 7,000 hectares to just around 700 hectares now –- throwing caution to the wind with regard to the ecological concerns.
But a new proposal by the Greater Chennai Corporation (GCC) to dredge the marshland as part of its efforts to mitigate flooding in the city has forced activists to red-flag the project. The activists say dredging would not just pose a threat to the biodiversity of the marshland, which is the only urban wetland here, but also to the city’s landscape.
The marsh, which is the last remaining natural habitat in Chennai, houses 167 species of plants, birds (178), mammals (10), reptiles (15), amphibians (11), fishes (50), butterflies (34), phytoplanktons (73), and dragonflies (20), among others.
A natural habitat for endangered reptiles like the Russell's Viper and birds like Glossy Ibis, the Pallikaranai marsh has been a birdwatcher’s paradise for long, activists say. Not just government buildings and a dump yard, numerous apartment complexes have also come up in Pallikaranai in the past few decades, they say and warn that any move to dredge the remaining marshland will only increase flooding in the city and not decrease it by any stretch of the imagination.
“If the project of dredging the marshland sees the light of day, it will make the city more vulnerable to floods than it is today. The project will also dry out the landscape, making the region completely dry. Contrary to what the proponents of the project say, dredging will make the city struggle for groundwater,” Dr Jayshree Vencatesan of the Care Earth Trust told DH.
The project will increase the city's vulnerability to floods, and the government should stop giving “knee-jerk” reactions and focus on finding sustainable solutions to prevent flooding, Dr Vencatesan, who has been voicing support for saving the marshland, added.
When contacted, J Meghanath Reddy, Deputy Commissioner, GCC, told DH that the proposal was not to dredge the marshland but only to reduce the quantity of water reaching the ecologically sensitive area from other parts of the metropolis.
The activists want the government to protect the Pallikaranai marsh as India is a party to the Ramsar Convention on Wetlands signed in 1971 in the Iranian city of Ramsar. The government’s move to dredge the marsh comes despite it being a protected area since 2005 – activists say an announcement in this regard by then Chief Minister J Jayalalithaa had saved the land from being further encroached.
G. Sundarrajan of Poovulagin Nanbargal, an NGO fighting for the protection of the environment, said the civic body’s plan to treat the marshland like a water tank can lead to “great biodiversity loss".
“It is a stupid decision to dredge a marshland which is home to several rare species. Instead of dredging lakes like Chembarambakkam which supplies water to the city, the civic body wants to dredge a marshland. They should go all out to protect such marshlands and not destroy them. These are ecologically sensitive areas that are important for a city like Chennai,” Sundarrajan told DH.