CHENNAI: Apart from sewage draining into the Puzhal lake, Arappor Iyakkam, a citizen’s group, has found that the lake, one of the two major rain-fed reservoirs from where water is drawn for the city’s needs, was also plagued by seemai karuvelam trees.
The karuvelam trees are believed to be one of the reasons for ground water depletion while also impacting the water flow and impacting the waterspread area.
As it is, the lake that prawls across almost 4500 acres, recorded only 260 mcft storage level on Sunday against a full capacity of 3300 mcft. Last year, it recorded 1782 mcft during the same time.
“Even in houses very close to the lake, borewells sunk to even 200 feet do not fetch water,” said Harris Sulthan, Arappor state body member, who coordinated the audit.
The lake, according to members who were a part of the audit, had sullage from areas such as Venkatesan Nagar and West Balaji Nagar in Thirumullaivoyal draining into it, via storm water drains or by direct connections.
According to Harris, desilting was also inconsistent in many parts of the lake, leaving behind craters.
“The permission given for sand quarrying here is an issue to be looked into. In this case, desilting is done in only specific areas according to the convenience of these quarries and the rest remain untouched,” he said.
In addition, the team also claimed that the banks of the lake had flattened out, opening up scope for encroachment.
The Arappor team, that carries out social audits almost every week, said it would also look into the Ambattur, Kotteri and Retteri lakes in the coming weeks.
Fact file
Puzhal reservoir was originally built during colonial times with a capacity of 500 million cubic feet and was extended in 1997 to a storage capacity of 3300 mcft
Average depth:
50.20 feet (15.30 m)
Primary outflows:
5470 (cusecs) Highest
Primary inflows:
9607 (cusecs) Highest
Surface area:
4,500 acres (18 km 2)