The Kolkata Municipal Corporation will desilt and refurbish a brick sewer line between Moulali and the Palmer’s Bridge drainage pumping station in Entally, which was built in the 1870s, and plays a crucial role in draining out rainwater from central Kolkata.
The 1.1km drainage line carries rainwater coming via sewer lines under Lenin Sarani and APC Road to the drainage pumping station, from where it is drained out of the city through a canal.
If the speed of rainwater flowing through the 1.1km-stretch slows down, the areas in its backyard suffer from waterlogging on days of heavy rain, said a KMC official.
Some arterial roads that will benefit from the desilting work are Lenin Sarani, APC Road, Central Avenue, Camac Street, AJC Bose Road, Park Street, Loudon Street, Rawdon Street, Rafi Ahmed Kidwai Road, Free School Street, Elliot Road and Ripon Street.
Officials said a larger command area, comprising smaller roads draining out water into the sewer lines under the arteries, will also benefit.
“The desilting of sewer lines between Moulali and the Palmer’s Bridge drainage pumping station will benefit large parts of north and central Kolkata. This will largely reduce the remaining waterlogging problems in north and central Kolkata,” said Tarak Singh, mayoral council member in charge of drainage department of the KMC.
The sewer line between Moulali and the Palmer Bridge station is part of an 88km-long network of man-entry brick sewer lines under Kolkata’s roads. This category of sewer lines is called ‘man-entry’ because it is large enough for a person to stand inside and fix problems.
The construction of these lines started in the 1870s. The stretch from the Moulali crossing to the Palmer Bridge is part of a longer line between Raj Bhavan and Palmer Bridge drainage pumping station. It is one of the first underground sewer lines to be built in Kolkata.
The desilting and refurbishment of the stretch between Raj Bhavan and Moulali was completed over 10 years ago, but the remaining stretch till the drainage pumping station has remained silted and in need of repairs.
After desilting, a glass-reinforced polymer liner will be fitted on the inside walls of the brick to strengthen it.
The work will cost Rs 175 crore. The tender inviting bids for the refurbishment work is likely be floated after the Lok Sabha elections, said a KMC official. “We will keep the tender document ready so we can float it once the model code of conduct for elections ends,” he said.
From the Moulali crossing, the sewer line goes under the manufacturing store of the KMC in Moulali, crosses the railway line and goes to the drainage pumping station.
Part of the project cost includes Rs 30.81 crore that has to be paid to the railways for working under railway tracks.
The KMC is yet to finalise the deadline to finish the project from the day of its start.
The civic body will also start desilting 5.7km of man-entry brick sewer line between RG Kar crossing of Raja Dinendra Street and Palmer Bridge drainage pumping station.