The Greater Chennai Corporation has identified 93 places in 23 localities, which are prone to flooding during the monsoon, to build storm water drains. However, there is flooding in these spots only when the rainfall is above 18 cm per hour.
The civic body’s flood-monitoring officers, who visited most of the identified spots in the central parts of the city, found that the cause of flooding was old storm water drains built more than 30 years ago.
A senior official said the construction of new drains, after demolition of the existing structures, had been taken up at more than 50 places. In a few places, the absence of links to the nearby network of drains was causing flooding.
Desilting work
The civic body has drawn up a plan to undertake desilting of storm water drains and major canals to have a flood-free monsoon. Local officials have been asked to identify, by the middle of July, vulnerable areas and structures which have to be cleaned, ahead of the tender process.
Spread across 15 zones, the length of the network of drains is estimated to be about 2,000 km in the city, said the senior official.
The civic body maintains 30 major canals, including the Kodungaiyur, Captain Cotton and Padikuppam ones. Commissioner Gagandeep Singh Bedi had ordered clearing of major canals using modern machinery, such as mini-amphibian vehicles, robotic excavators and floating trash booms.
The civic body normally allocates ₹5 crore for each region in the city, which has been segregated into three — north, central and south — with the Regional Deputy Commissioners (RDC) heading the regions allocating the amount proportionately to all the 15 zones as per the local requirement.
The senior official said once the estimates were prepared by the assistant engineers of all the 200 divisions, estimates would be verified by the zonal heads, comprising assistant executive engineers, executive engineers and zonal officers, for recommendation to the RDCs.
The local officials were identifying places where desilting of drains needs to be undertaken and once the list is compiled, the Regional Deputy Commissioners will give administrative sanction for calling tenders.
Plans are afoot to start the work by the first week of August and complete it by October-end.
The civic body, after the December 2015 floods, had divided the 15 zones into the basins of Kosasthalaiyar, Kovalam, Adyar and Cooum. While work on the storm water drains had been completed in the Adyar and Cooum basins, a portion of the work was yet to be completed in the Kovalam basin.
The civic body would be executing the work in the Kosasthalaiyar basin, covering major parts of north Chennai.
