Kolkata Municipal Corporation has completed the zero-desilting restoration of a 2.1-kilometre underground drainage network between the Ultadanga pumping station and Bengal Chemicals after around 18 months of work, in a move aimed at improving water discharge from several waterlogging-prone areas.
Municipal administrator Smita Pandey inspected the restored drain on Wednesday and went inside the underground system to review the work. Civic officials said the project cost ₹5.57 crore. The drainage network carries stormwater from Ultadanga, Kankurgachi, Maniktala Main Road, the EM Bypass and parts of Salt Lake towards the Dhapa pumping station.
Heavy rain in recent monsoon seasons has caused substantial water accumulation around Ultadanga’s HUDCO crossing and the junction between Bidhannagar and Ultadanga. Although pumps at the Ultadanga pumping station were used to remove the water quickly, the underground drainage system’s carrying capacity had reduced over time because of accumulated silt.
The restored section runs from the Salt Lake Gate near Ultadanga to Bengal Chemicals. A large box drain passes from the pumping station through the Salt Lake crossing and beneath the EM Bypass. Another brick-lined underground drain runs nearby towards the Dhapa Lock Gate pumping station. Together, the two drains serve multiple wards in the Ultadanga area and parts of Salt Lake.
According to officials from the civic body’s drainage department, the underground drainage system had been accumulating silt for several years. It was built in 1990 and had not undergone significant desilting since then. The civic body therefore decided to remove the accumulated material and restore the system’s capacity.
The work was complicated by concrete deposits inside the drain. Civic officials told the administrator that several high-rise buildings had been constructed in the surrounding area, and that liquid used during piling, along with cement slurry, had entered the drainage system during construction and hardened. Workers had to break and remove large concrete pieces from inside the drain.
Shantanu Kumar Ghosh, director general of the civic drainage department, briefed Pandey on the problem. After the inspection, Pandey said residents also had responsibilities in protecting public infrastructure. She questioned when fines would be imposed if piling water was discharged into drains, according to the report.
The civic administration said the restoration should reduce the waterlogging problem faced by local residents. The next operational test will come during heavy rainfall, when the restored system is expected to carry excess water from the connected neighbourhoods towards the pumping infrastructure.
