The flooding of residential neighbourhoods across the city has left many residents marooned.
After the deluge in 2015, the Greater Chennai Corporation and other line agencies came up with proposals for various infrastructure projects to reduce flooding in 498 locations, based on the report of flood monitoring officers. Among the proposals was improving the drainage system to handle a precipitation of 70 mm per hour.
But this week, residents complained about flooding in as many as 317 locations. Over 5,000 complaints were received by Corporation officials in the past three days.
Corporation Commissioner Gagandeep Singh Bedi on Monday said water had not receded in as many as 177 of the 317 residential neighbourhoods.
Though the civic body cleaned drains this year, most of the major infrastructure projects remained incomplete ahead of the monsoon. A case in point is the work on the restoration of the Mambalam Canal from Valluvar Kottam to Saidapet. In 2020, the civic body announced that the Mambalam Canal would be restored in 9 months. But the project has faced delays. Illegal dumping of garbage into sewage inlets and encroachments on the canal continue to hinder the flow of water from areas like T. Nagar.
As regards the Kosasthalaiyar river basin, the Asian Development Bank had sanctioned a loan for a ₹3,220-crore project covering 769 km of drains. But the Corporation has not yet completed work on 600 km of drains, leading to flooding in the northern parts of the city. The development of drains for a length of 325 km in the southern parts of the city, funded by KfW, also remains incomplete. Work on missing links was carried out in areas like T. Nagar at a cost of ₹350 crore. But encroachments on canals including the one in Mambalam have led to flooding in several neighbourhoods.
Former urban planners of CMDA pointed to the issue of the reduction in the width of canals like Buckingham Canal in many parts of the city.
The Corporation maintains 2,070 km of stormwater drains on 9,224 stretches in the city. It also maintains 30 canals with a total length of 48.8 km. But major proposals to develop underground canals to drain water from the southern parts of the city are yet to be implemented.
Work on the development of drains across railway tracks and highways at 23 locations has not been completed despite administrative sanction having been issued before the monsoon.