The municipality’s lack of equipment and expertise to detect crumbling underground utilities has claimed its latest casualty — a road at Kalachowkie caved in on Monday morning.
A trench 10 ft deep and 10 m x 20 m across (large enough to swallow an average car) opened up at Shravan Yashwant Chowk off P D’Mello Road at Kalachowkie, near a BEST bus stop.
Civic officials said leaking underground utilities could be the cause. Ashok Shintre, director (Engineering Services and Projects) said: “The cavity was likely caused by old, rotting underground utilities, most likely a storm water drain.”
This is the city’s sixth cave-in in the last three years. Locals and witnesses said that seconds earlier, bus number 52 had stopped at the same spot. “Had the bus waited a few seconds longer, it would have been far more serious,” said Dattaram Patil, a local.
This was the first road concretised in the city in 1984. The life of a cement concretised road is around 40 years. On one side of the road is a 9-mm water pipeline, on the other, an 18-mm water line. There is also a sewage main 23 ft under the road, and a storm water drain above this main.
“Before we can begin repairs, we’ll have to excavate the cavity, and also open up the adjoining area to determine what utilities it contains,” Shintre added. Routes for more than seven BEST buses were diverted, and the entire area cordoned off, immediately setting off traffic snarls in multiple directions.
The municipality has not done anything to prevent multiple cave-ins that have occurred since 2007, starting with the one at Prarthna Samaj. After a stretch of road caved in at Jacob Circle in 2008, the BMC had commissioned a survey of underground utilities with the help of a professor from the Veermata Jijabai Technological Institute. The BMC still has no conclusions from that survey drawn.
“We then asked a private firm to do sample surveys for us. They covered two places – Jacob Circle and Rakhangi Chowk at Worli – but haven’t been able to process the data,” a Roads Department official said.
Experts have also said the chronic lack of coordination between the BMC’s various departments is a factor in incidents like this.
“The Roads Department needs more co-ordination with other departments like Sewage, and Water, so it knows which underground utilities will be affected. It also needs to take sample bores to test the condition of sub-surface earth before laying new slabs,” said N V Merani, chairman of the Standing Technical Advisory Committee.
“Also, reports from earlier investigations are not taken serious at all,” Merani added.