The Kolkata Municipal Corporation (KMC) will desilt and strengthen the century-old brick sewer lines under Elliot Road, Royd Street, Rafi Ahmed Kidwai Road and Nirmal Chunder Street — a corridor where several stretches are notorious for waterlogging.
A civic official said the city has 88km of such brick sewers, and the KMC plans to cleanse and reinforce the entire network.
Calcutta’s brick sewer system, built by the British between 1878 and 1888, comprises an 88km network of “man-entry” sewers, whose diameters are large enough for a person to stand inside. About 30km of these lines were desilted under the now-defunct Jawaharlal Nehru National Urban Renewal Mission (JNNURM), starting in 2005.
Another 9km of brick sewers are being desilted at present.
“We still have 79km of brick sewer lines left to be desilted and strengthened. These were built by the British and have seen no major intervention since they were commissioned more than a century ago. The diameters have shrunk and the sewage flow has reduced over the decades,” a KMC official said.
The official added that the new project covering Elliot Road, Royd Street, Rafi Ahmed Kidwai Road and Nirmal Chunder Street is part of the larger endeavour to revive and reinforce the city’s oldest sewer infrastructure. “This will extend the life of the brick sewers, and the sewage flow will be unobstructed,” the official said.
The state urban development department is funding the project. Officials said bids have been invited and the start of physical work will depend on how soon the tender process is completed. The KMC has set a three-year deadline for completion.
“Pits will be dug at intervals so workers can access and clean the sewer line. The entire road will not be cut open,” another official said. After desilting, a GRP liner will be installed inside the brick sewers to reinforce them.
Several stretches along the corridor identified for desilting are known trouble spots during rain. “The stretch outside the junior section of Assembly of God Church on Royd Street gets waterlogged after every shower. During an intense spell, the water rises to knee level and remains for at least half a day,” said a resident of Rafi Ahmed Kidwai Road.
“The road near Saldanha Bakery is also prone to flooding,” he added. Waterlogging is worse in the lanes branching off the arterial road, since the main road is at a higher elevation.
The city’s first underground sewer line was commissioned in 1878 along Lenin Sarani and completed in 1888.
Currently, desilting of century-old brick sewers is underway along a 2.5km stretch of BB Ganguly Street, 5.7km of Raja Dinendra Street and over 1km of Abdul Halim Lane.