Scenes of flooded streets in and around Koyambedu may not be repeated this monsoon season, if the project to construct a diversion channel from Virugambakkam-Arumbakkam canal to Cooum river, proceeds as per schedule.
Every monsoon season, residents of Valasaravakkam, Choolaimedu and Koyambedu contemplate moving to other areas, as their localities are completely submerged.
Residents of Gandhi Road, Choolaimedu said that the width of the canal shrunk near Razak Garden. Whenever surplus water from a chain of water bodies near the Chembarampakkam reservoir was released into the canal, localities stretching from Valasaravakkam and Saligramam to MMDA Colony and Mehta Nagar became inundated. The canal and stormwater drains must be desilted completely to prevent flooding in the surrounding areas, they said.
Demand for desilting
The Water Resources Department (WRD) must initiate steps to desilt the stretch of clogged canal near the underpass on Jawaharlal Nehru Salai, Arumbakkam, where the widening work has been suspended, they added.
The WRD, which had earlier proposed a diversion channel through Jawaharlal Nehru Salai near Arumbakkam, hit roadblocks owing to problems in getting permission from other government agencies.
The department has now chalked out another project to carry the surplus water from the canal and changed the alignment of the diversion channel. Instead of the intersection at Jawaharlal Nehru Salai near Arumbakkam, the new channel will begin from Chinmaya Nagar, travel through Kaliamman Koil Street and join Cooum river near the Koyambedu grade separator.
“We have started preliminary work to construct the channel. There will not be much of a problem in implementing this project, as concurrence from other government agencies has been obtained. Moreover, the 2.15 km-long channel will be constructed using pre-cast technology,” said an official.
At present, the Virugambakkam-Arumbakkam drain can carry only 1,000 cubic feet of water per second (cusecs). The width of the canal, which is 15 metres near Chinmaya Nagar, gets shrunk to 8 metres when it reaches Azad Nagar, Thiruvalluvarpuram and Nelson Manickam Road. Adjoining localities bear the brunt during rains, as the canal's capacity is reduced.
The proposed 4-metre wide channel, which will have pre-cast concrete structures, will carry 400 cusecs and join the Cooum river. The WRD's hope to complete the Rs. 33.80 crore project before the onset of the Northeast monsoons stems from the use of pre-cast technology.
“We will construct the structures elsewhere. We are planning to lay it out over a distance of 26 metres daily. Traffic problems at these busy junctions can also be mostly avoided,” the official said. Work to construct the channel will commence in a few days. Areas that will escape inundation include Sai Nahar, Majid Nagar and Railway Colony.
Enumeration of encroachments
The department is also simultaneously enumerating encroachments along the 6.3 km Virugambakkam-Arumbakkam drain. “We plan to complete desilting and construction of a retaining wall by the end of October,” a WRD official added.