Ludhiana, Aug. 11 -- The municipal corporation is preparing a plan to rehabilitate a nearly 50-year-old brick trunk sewer running beneath several key areas of the city, following a series of road cave-ins linked to damage to the ageing sewer. "The MC plans to reinforce the existing structure with concrete rather than replace it, with the rehabilitation cost estimated at around Rs.50 crore per km," municipal corporation commissioner Ojasvi Alankar said.

A trunk sewer is a large-diameter public sewer pipe that acts as a main artery in a wastewater collection network, gathering sewage from multiple smaller branch lines and conveying it towards a treatment plant.

"The immediate focus is a 2,100-metre stretch of the 2,850-mm-diameter sewer r...