Residents of north Chennai have urged the Water Resources Department (WRD) to expedite the improvement of the initial stretch of the Thanikachalam Nagar drain to reduce flooding in areas around Madhavaram and Retteri.

While a major portion of the Thanikachalam drain, which carries surplus water from Kolathur and Retteri lakes, was upgraded last year at a cost of ₹91.36 crore, residents noted that the work on the initial 750-metre portion of the channel is pending. The channel is only 10 metres wide now and stormwater drains from various localities such as Ambattur and Korattur are also linked to the channel, which finally flows into the Kodungaiyur drain.

‘Inadequate capacity’

T.K. Shanmugam, president, the Federation of North Chennai Residents Welfare Associations, said the inadequate carrying capacity has led to flooding in various wards of Madhavaram and Kolathur during heavy rainfall.

Pointing out that the encroachments have narrowed the surplus water channel, the federation has urged the department to build a cut and cover channel with a width of six metres to help alleviate flooding.

According to WRD officials, the Thanikachalam drain was built in 1998 and is nearly 3,050 metres long. It carries surplus water from waterbodies in Retteri and Kolathur through localities such as United Colony, Ramalinga Colony, and Thanikachalam Nagar.

It flows into the Kodungaiyur drain that confluences into the north Buckingham canal.

Officials said the department had reconstructed the existing channel and also built an additional channel in the stretch between 750 metres and 3,050 metres. The carrying capacity of the channel was improved to 1,000 cubic feet per second.

A detailed project report for widening the initial 750-metre stretch is awaiting government approval. The WRD would coordinate with Revenue Department to demarcate the channel’s boundaries and remove encroachments to facilitate the project, the officials added.

Published - July 26, 2026 05:00 am IST