The wait for relief from floods for residents of Koyambedu and its neighbourhood may now get prolonged.
The design for the box channel (which will resemble a stormwater drain) to divert surplus water from Virugambakkam-Arumbakkam canal to the Cooum river has been changed for the third time.
Under the new design, the channel will be constructed on the premises of the Koyambedu sewage treatment plant. It would then pass through a few hundred metres of Kaliamman Koil Road and Jawaharlal Nehru Salai before joining the Cooum river.
Residents of Koyambedu, Chinmaya Nagar and Virugambakkam who are often affected by floods every monsoon are concerned over the possibility that the project may not be completed this year.
The Water Resources Department (WRD) had proposed to construct a channel to divert the excess flow of 400 cubic feet per second from the Virugambakkam-Arumbakkam canal under the Jawaharlal Nehru National Urban Renewal Mission.
The original proposal to construct the channel via Jawaharlal Nehru Salai was dropped as it involved shifting of utility lines and co-ordination by various departments on the busy arterial road.
Earlier this year, the WRD got a revised detailed project report approved by the Central government. According to the second proposal, the diversion channel would travel via Kaliamman Koil Road in Koyambedu, Jawaharlal Nehru Salai and cross Poonamallee High Road to be linked with the Cooum.
But, this proposal too met with several stumbling blocks.
Officials determined that the construction of the channel on the 12-metre-wide Kaliamman Koil Road near the Chinmaya Nagar bridge would be difficult. A network of utility lines and large water and sewer lines crisscross beneath the road made it difficult to construct the four-metre-wide and two-metre-high channel.
The WRD has now sought Chennai Metrowater’s help to change the design to avoid digging up a large portion of the busy Kaliamman Koil Road. Shoba Giridhar, a resident of Virugambakkam, said the Virugambakkam-Arumbakkam canal has shrunk in size near Arumbakkam. “Whenever the water bodies in Porur and Chembarambakkam are full, the canal overflows. I have had to move to the first floor of my house for few days during floods at least twice since 2005 when floodwater seeped into the house and damaged valuable items,” she said.
Residents said they may face a similar situation this year too if steps are not taken to alleviate floods.
Sources in WRD said the length of the box channel would increase by 400 metre from 2,550 metre distance in the new proposal.
Once the channel, which will be covered with concrete slabs, is built, Metrowater could use it as an inspection road or let the treated sewage through it into the Cooum.
With the new design, which is now being scrutinised by Metrowater, the department is hoping to complete the project before October.