The Rettai Eri or Retteri in Kolathur, near Ambattur, spans across 700 acres and is often referred to as a haven for birds. It is even an eco-tourism spot.
However, the lake is far from alright in the current situation, say residents. Water hyacinths have taken over the lake and need to be cleared, they say.
“For most part of the year, the lake has water. Even if rains are meagre, the lake retains water. Now, water is not being taken for drinking and, hence, it became a haven for birds. About 40 different species of birds come to the lake every year, including the Asian open bill stork, which is a migratory bird. But the lake needs to be cleared of water hyacinths as it will make the water murkier and unfit for animals to drink,” said Gangatharan, a resident.
Covering 5.42 million sq metre, the waterbody also faces threat of native plant species being wiped out by invasive ones. A study done by Care Earth Trust, a biodiversity research organisation, states that Retteri is among the worst affected wetlands in the city.
About 60 per cent of the plant species has been overrun by invasive species in the past two years at the spot. But the biggest concern for residents is whether water in the lake will be saved from becoming unfit for drinking as each day passes by.
In July last year, when Chennai’s major reservoirs had a little over 20 per cent water left in them, Chennai Metrowater conducted a feasibility study to draw water from Retteri lake for the city’s water supply. According to officials, the lake has the capacity to store 110 million cubic feet of water.
With a failed monsoon, the city’s reservoirs hold water only to supply for another month. “This is what worries me. Water needs to be saved in the lake. The authorities should get down to action and clear the lake of weeds immediately. Water is precious and I think we fail to understand that at most times,” said Arumugam, a resident.
“If the lake is not saved in time, then Chennai will have a vast waterbody that will not be of any use. Then, the government will have to resort to tapping water from quarries once again,” he added.