NDMC set to upgrade sewer networks near Khan Mrkt to tackle waterlogging

A senior civic official said that a series of infrastructure improvement projects will be executed to improve the storm water drain network before the onset of next year’s monsoon.

In a step towards tackling the recurring problem of waterlogging in Lutyens’ Delhi, particularly around the Golf Links and Khan Market areas, the New Delhi Municipal Council (NDMC) plans to initiate a project to isolate the trunk sewer line from the brick-barrel storm water drain at the Q-Point near Khan Market along with to rehabilitate old sewer lines.

Waterlogging after a short spell of rain in New Delhi. (HT Photo)

A senior civic official said that the bids for the project have been invited and the project is likely to cost around ₹3.47 crores. “Once an agency is finalised, it will take almost four months to complete the project,” the official added.

A senior civic official said that a series of infrastructure improvement projects will be executed to improve the storm water drain network before the onset of next year’s monsoon. “The project involves advanced sewer rehabilitation and cleaning techniques, including manual jacking of pipes, desilting, removal of blockages, and structural strengthening. The works will also include CCTV surveys of the existing lines, manual excavation and installation of mild steel pipes coated with epoxy for improving durability,” official added.

The Q-point is located at the intersection of the key avenue roads such as Prithviraj Road, Abdul Kalam Road, Motilal Nehru Marg, Shahjahan Road and Man Singh Road.

The complete drainage system of the NDMC area lies between the Delhi Ridge [check] in the west, the Yamuna in the east and the Ring Road in the south. NDMC areas comprise 578 km of covered drains with 11,907 drainage manholes and 14,264 bell mouths. The long-term plan includes rehabilitation and strengthening works amounting to at least ₹1,597 crores. Of the various drainage subsystems, the maximum discharge of rainwater occurs through the brick arch barrel from Q-point to Sunehri Pulla via Bharti Nagar and brick barrel running via Arch Bishop Marg--each of which gets 1,060 to 1,235 cusecs of water during heavy downpour.

Before the Q-Point project is initiated, the agency will undertake blocking of sewer lines and branch connections for diversion of flows. Officials said that minimal digging work will be undertaken to ensure traffic is not disrupted.

“Over time, increased sewage flow and urban expansion have overwhelmed the capacity of the existing system. The work will also involve complete cleaning and desilting of the 1675 mm to 2100 mm diameter lines, and removal of old CIPP liners and other obstructions,” official added.

Officials believe that once completed, the project will significantly reduce the risk of flooding around Golf Links, Pandara Park, Lodhi Estate, and nearby roads, improving stormwater discharge efficiency and public hygiene. “This is part of NDMC’s ongoing efforts to modernise its underground infrastructure while preserving the heritage network that forms the backbone of central Delhi’s utilities,” the official added.

NDMC maintains about 350 km of sewer lines in the New Delhi area, spread over an area of 42.7 square kilometres.

“The sewage lines are varying sizes ranging from 350mm to 2100 mm diameters but most of the lines are more than 70 years old. These old lines need augmentation and replacement,” NDMC official said. New Delhi has seen several road cave-ins triggered by the collapse of sewage lines at places like Ashoka Road, Windsor Place, C-Hexagon near India Gate, Mandi House, and Shershah Road, among other places.

The civic officials said that over the decades, the corrosive gases from these sewer lines have peeled off the outer layers. “This leads to collapse or settlement every year during the monsoon season,” an NDMC official said, adding that some of the sections in these lines have already been rehabilitated.

“NDMC has taken up phased rehabilitation of sewer lines based on a detailed consultancy. The first phase of rehabilitation of about 30 km of sewer line and 10 km under phase-2 has been completed and it will be expanded to a much larger scale over the next 5 years.”