The southern suburbs along the Adyar river may not face flooding this monsoon as the Water Resources Department (WRD) has expedited the construction of a diversion channel from Somangalam tributary-Adyar confluence point.
The channel is expected to divert excess water from this point to the downstream portion of the Adyar river near Vandalur-Walajabad Road.
Nearly 40% of the work on the channel has been completed. The department plans to complete the work ahead of the monsoon.
Every monsoon, areas like Mahalakshmi Nagar, Ashtalakshmi Nagar in Varadharajapuram and West Tambaram that are at a lower altitude than the Adyar get flooded whenever the river flows at its maximum level. Officials said the channel would carry a portion of surplus water of 1,000 cusecs to downstream where the river was wider. This would prevent flooding of neighbouring areas.
Surplus water of several tanks and tributaries upstream join the river. However, the culvert capacity was inadequate near these flood-prone areas along the Outer Ring Road.
About ₹70 crore would include work to increase the depth and enhance the flood-carrying capacity of the river for 13.2 km. The department will be spending a share of the project cost on strengthening the bund and on building flood protection walls, particularly between Adanur and Tiruneermalai.
These works would prevent breaches in the river during heavy flow in the waterway. Dense rocks in the riverbed in the upstream portion would be cut to facilitate smooth flow. The Adyar had carried a peak flow of nearly 20,000 cusecs in upper reaches during monsoon last year, the officials added.
