Traffic crawled for kilometres on the Delhi-Gurgaon Expressway on Wednesday as repair work continued on a section near Narsinghpur that caved in after heavy rain.On Tuesday, the cave-in, caused by pipeline work and the rain, disrupted one of the NCR’s busiest arterial roads. Authorities had barricaded two lanes on the Jaipur-bound carriageway, triggering major traffic congestion during peak hours.On Wednesday, some employees of nearby factories and Bestech Cyber Park chose to walk the final stretch given the slow traffic. “It was taking very long to cross so we have decided to go on foot,” two professionals said, navigating a muddy part of the service road.Dharm Veer Singh said he reached home — a highrise in Sector 82 — from Delhi three hours later than usual on Tuesday. “Even an hour and a half after crossing Ambience Mall, I had only reached Sector 15 (near 32nd Avenue). So I took the Dwarka Expressway then,” he said.All three lanes of the Delhi-Gurgaon Expressway will be open to traffic by Wednesday evening, National Highways Authority of India (NHAI) officials said.“Two out of three lanes had to shut for traffic yesterday. We have already opened one, and the remaining one will also be opened up by the evening. We are just ensuring it is sealed properly with soil because the road sees heavy truck traffic,” said an NHAI official. Repairs continued through Wednesday; all lanes are expected to be opened to traffic by evening. (Express Photo)What caused the cave-in?The collapse took place at a location where the Gurugram Metropolitan Development Authority (GMDA) is laying a pipe beneath NH-48. The incident left a large crater on the expressway.Story continues below this ad“NHAI would like to inform that a localised cave-in has occurred on a portion of NH-48 near Narsinghpur (Delhi-Jaipur side) at a location where @OfficialGMDA was carrying out pipe culvert pushing works,” the Authority said in a statement.A culvert is a pipe for water that goes under a road.“The GMDA was pushing one of its pipes from left to right, and we did not expect such heavy rainfall yesterday. The water eventually seeped in from the pipe that was being pushed in and emerged on the other end, which led the area to settle and crater in,” explained an NHAI official. The cave-in, however, resulted in a traffic jam stretching for kilometres (Express Photo)A GMDA engineering team official present at the site blamed the cave-in on the persistent rain.Story continues below this ad“We were putting in place two pipes to connect to the temporary drain that is in process of being concretised and was carrying runoff. Because of the heavy rain, water seeped through. If it had rained even two days later, the cave-in would not have happened,” the official said.“Nearby industries also tend to release their drainage directly here despite our instructions, adding to the load,” he added. The NHAI official said they have told all agencies involved in pipe-pushing to stop such work until the monsoon ends. (Express Photo)What precautions will NHAI take going forward?The NHAI official said they have told all agencies involved in pipe-pushing to stop such work until the monsoon ends.GMDA officials said the cave-in was covered up by 9 pm Tuesday, and the remaining pipe installation work will be completed depending on the spells of rain ahead.Story continues below this adWhat was the aftermath?The cave-in, however, resulted in a traffic jam stretching for kilometres, with many commuters reporting delays ranging from an hour to a couple of hours.Traffic Police had to create diversions through Dwarka Expressway and Southern Peripheral Road.It also issued a cautionary advisory requesting corporate employees to work from home due to the inclement weather. “We strongly urge the corporate sector and private establishments to encourage Work from Home (WFH) arrangements for their employees for the next few days. Minimising non-essential vehicular movement will greatly assist our traffic management teams in maintaining the flow of traffic and ensuring emergency services remain unobstructed,” the police said in a statement.