The Water Resources Department is set to restore 28 channels in the city. While temporary works are being carried out to ahead of the northeast monsoon, the department is set to begin work on a significant portion of the project by January next year.
Drains running to a length of 85 km function as vital links to carry excess water from waterbodies and residential areas to various waterways. The department has now chalked out a project worth about ₹821.44 crore to rejuvenate the waterways linked to the Buckingham Canal, the Adyar and the Cooum rivers and prevent flooding of adjoining areas during heavy flow.
Officials said improvement work had been started on a few drains and tenders were being finalised for other works under the aegis of Chennai Rivers Restoration Trust. The drains to be rejuvenated include the 10.26-km-long Otteri Nullah, Veerangal Odai, Adambakkam Canal, Korattur Surplus Canal, Pammal drain, Manimangalam Karasangal drain and Pallikaranai Marsh Canal.
Besides widening and desilting the channels, retaining walls would be built at vulnerable portions to prevent dumping of solid waste and encroachments. Flood-carrying capacity of the drains would be increased. There are plans like waterfront development similar to projects proposed for the Cooum and the Adyar.
The department is now carrying out preliminary survey to delineate boundary for Meenambakkam drain and Thirumudivakkam drain.
Officials said the ₹99.10-crore work to rejuvenate Somangalam Malaipattu drain, which flows into the Adyar, is being executed. The bund is being formed for the entire length of 9.74 km of the canal and a wall was being constructed. The channel would be able to carry double its present capacity of 2,000 cubic feet per second when the work is completed in March.
Once the 28 channels are restored, their carrying capacity would be go up by about 30%-40%. Some of the channels would be dredged by a minimum of 2 feet to enable quick draining of water into the rivers.
The department plans to improve Ainsley Canal that joins Otteri Nullah near Konnur High Road and North Kodungaiyur drain, which it had recently taken over from Greater Chennai Corporation.
While lauding the efforts, residents wanted the canals to be restored in their entirety. Pointing out to gaps in floodwater flow from Pachamalai Hills to Chitlapakkam, P. Viswanathan, convenor of Chitlapakkam Residents Association Coordination Committee, said the projects must ensure that rainwater from channel reach their destination whether a lake or river and prevent inundation.