The Basanti Road stretch that caved in early on Friday. Picture by Pradip Sanyal

A gaping hole, 13-ft deep and seven-ft wide, greeted motorists on Basanti Road on Friday. The concrete sewerage pipe underneath a stretch of the only highway link between Calcutta and the Sunderbans sprang a leak leading to the cave-in.

Traffic movement was hit from early on Friday. A large police contingent barricaded the caved-in portion. As a temporary measure, bricks were laid beside the caved-in road to allow vehicles to ply.

Later, irrigation department officers in charge of the maintenance of sewerage pipes, and officials of the public works department (PWD), the agency which maintains the road, inspected the site. The 13-ft-deep ditch was filled with sand and bricks.

Those who witnessed the cave-in around 5 am, immediately alerted the local police. “It happened in a fraction of a second. Moments before the cave-in, an overcrowded bus had passed by,” Ranjit Das, a local resident, said.

PWD had repaired the road about eight months ago. The road is over 45 years old. In 1990, it was widened from 10 ft to 18 ft, officials said.

“The cave-in was caused by the leakage of drainage pipes under the road. The pipes are over 40 years old,” said Debashis Ghosh, executive engineer (highway division) of PWD.

“The leakage in the underground sewer line loosened the earth below the road surface and weakened its compaction. The road then caved in under the vehicular load,” he explained.

A blame game broke out between the irrigation department and the PWD. “See, the road was repaired only eight months ago and the implementing agency did not even bother to carry out preliminary inspection,” an irrigation department officer said.

“The irrigation department is in charge of maintenance of sewerage pipes and it must conduct inspection on a regular basis,” countered PWD’s Ghosh.