For residents of Chennai suburbs, the fear of flooding looms again

Chennai faces flood risk due to poor drainage infrastructure and encroachments, requiring urgent structural and environmental solutions.

With the rain lashing several parts of the State, residents of Chennai and its suburbs have but only one fear: what will happen to them during the northeast monsoon or earlier, if there is a cloudburst during the southwest monsoon.

Chennai can face inundation this year too in the event of incessant rain as it was the case when Cyclone Michaung struck the city in December 2023, Chief Secretary Shiv Das Meena has said. On May 25, he inspected the problem areas in the Greater Chennai Corporation’s Zone 10 (Kodambakkam), Kovalam Basin, Anakaputhur, Pammal, Chitlapakkam, Irumbuliyur, Guduvanchery, Polacheri, and Thiruporur.

All the rainwater from the lakes in Kancheepuram and Chengalpattu districts must pass through the Chembarambakkam lake, the Buckingham Canal, the Cooum and the Adyar in Chennai city to reach the sea, and this is the main reason for inundation, Mr. Meena has said. There are 25 waterbodies upstream of the Chembarambakkam reservoir. From the catchments of this reservoir, water is flowing to the Adyar from 340 waterbodies, of which nearly 240 are upstream of the Mudichur lake.

He has said, “The State is working on many solutions. Additional passageways are being created for water in many areas to quickly drain into the sea. Roads near the waterbodies may be flooded, but we expect the water to recede faster. Last time, the situation was unprecedented. We are continuously improving the storm water drain network in the southern region [of Chennai], including Kovalam. Desilting will also be done. But if there is continuous heavy rain this year too, some inundation may take place. We have to prepare mitigation and relief measures, and we are working on them.”

R. Srinivasan, 36, says that for the first time, flooding up to 3 to 4 feet was noticed in his area — Pattunool Chathram in Sriperumbudur — during the cyclone in December 2023. “We have never seen water entering homes. Further, owing to incomplete storm water and sewage drains in the township, wastewater entered the lanes. The two-laning of the Kundrathur-Sriperumbudur State Highway reduced the size of the 10-foot culvert abutting it, causing water from the Sriperumbudur lake to enter the township.”

After several parts of Chennai were marooned last year, Arappor Iyakkam, under the aegis of ‘Makkal Medai’, released an audit of the flooded areas, setting forth the reasons for inundation and solutions.

Among them was the Medavakkam Sitheri lake, in Ward 8 of Ranganathapuram, Medavakkam Panchayat, Chengalpattu district, which is surrounded by Vijayanagaram and Ranganathapuram upstream and CBI Colony downstream. It receives water from the Nanmangalam reserve forest through canals crossing the Medavakkam-Tambaram Road. In 2023, the lake breached, flooding R.G. Nagar and CBI Colony, according to the audit.