Even after crores were spent on desilting Powai lake, deepening and widening it and beautifying its periphery, untreated sewage from the 16 nullahs that connect to it keeps seeping into the water body.
This is despite the fact that gates were built in 2006 to close these culverts off.
The sewage water has led to an alarming growth of hyacinth on the surface of the lake, said civic officials from the hydraulics department of the BMC.
“As hyacinth grows, the oxygen content dissolved in the water decreases,” said Shirish Patil, sub-engineer, who has been in charge of the upkeep of the lake for the past four years.
“This poses a grave threat to the aquatic life, flora and fauna that thrive in the lake,” said Nutan Bhalla, Powai resident and a member of Action for good Governance and Networking in India (AGNI).
Activists and civic officials said that illegal drainage connections and mushrooming slums have adversely affected the health of the water body. “What is needed is a strong-willed, concerted effort from all civic departments concerned to bring a halt to this pollution,” said Pamela Cheema, coordinator of CitiSpace and AGNI, who lives in Powai.
“There is an urgent need to stop the flow of sewage water into the lake. The culvert gates are sometimes opened by anti-social elements to allow the sewage water to flow into the lake,” said Manohar Pawar, executive engineer (water works, civil maintenance).
Activists also claimed a large amount of hard silt remains in the lake and that its desilting was shoddily performed. “The lake’s original depth needs to be restored. Much of it is yet to be desilted,” said SK Saksena, an engineer who has lived in Powai for the past 17 years.
Activists have now demanded that sentries be stationed at the culvert points to ensure that the gates are not opened.