Chennai: Southern parts of Chennai, usually prone to prolonged and severe flooding during cyclones, remained largely unaffected on Saturday as Cyclone Fengal passed over the city. Learning from the impact of Cyclone Michaung in Dec 2023, the govt addressed key issues by removing encroachments from certain lakes, widening Okkiyum Maduvu, and partially draining water bodies by Sept.
While South Chennai received only around 12cm of rainfall on Saturday, these areas often flood more because there is no place for the water to go. Floodwater drains via a chain of lakes, then enter the Pallikaranai marshland and exit into the Buckingham Canal. However, many are encroached, silted up, and even missing, which results in water bodies breaching.
WRD partially drained several flood-prone lakes, including Narayanapuram Lake, which is the last in the chain receiving surplus water from Pallavaram, Velachery, Sunnambu Kolathur and Adambakkam lakes. This makes Narayanapuram Lake highly prone to breaches as its overflow drains into the Pallikaranai marshland. Last year, the lake bund breached, causing the wall to collapse onto Velachery-Tambaram Main Road. In Oct 2024, WRD removed four temples encroaching on the bund and partially drained the lake.
Additionally, WRD widened the Okkiyum Maduvu by expanding into 2.7 acres of private land in Karapakkam at a cost of 30 lakh. GCC is set to officially acquire the land in 2025.
WRD has nearly cleared four houses encroaching the Keelkattalai surplus channel, which carries water from Tambaram lakes. "While they have gone for a stay order, we will remove the parts of the houses encroaching the canal," said Selva Kumar, executive engineer of Kovalam Basin, WRD. A 53 crore retaining wall project has also been tendered, set to start post-monsoon.
"Areas such as Semmancheri, Arasankalani, Perumbakkam, Madhurapakkam and Ottiyambakkam used to experience hip-to-neck-deep flooding that took more than 10 days to drain. However, with the recent construction of a 103 crore cut-and-cover drain, water now drains in just two days," said the engineer.
Sankar J, coordinator of the federation of Sunnambu Kolathur residents welfare associations, said, "Due to encroachments being removed from the Keelkattalai surplus canal, the channel did not overflow in Sunnambu Kolathur and Eechangadu near Radial Road. But some cut-and-cover drain projects are pending."
The 40 crore drain project linking Narayanapuram Lake to the Pallikaranai marshland is only 20% complete. "The highways department delayed granting permission to cut the road for the drain. We plan to complete it after the monsoon," said the WRD official.