The Kolkata Municipal Corporation (KMC) has drawn up a list of 38 roads across the city that will undergo “a thorough repair” ahead of monsoon, mayor Firhad Hakim said on Saturday.
These roads now offer bumpy rides because of undulating surfaces and the civic body wants to put a layer of mastic asphalt on top.
“Kolkata’s roads are not always in bad shape. But they offer bumpy rides,” Hakim said. “If one drives at a slight speed, there is a roller coaster effect. We are now looking at an engineering solution to this problem.”
Officials said the repair would comprise two aspects. One strengthening the underground layer that comprises a mix of alluvial soil and sand, which keeps sifting with water seeping in. Two — the road surface would be re-laid using mastic asphalt that has been prepared using a German technology.
Engineers repairing roads in Kolkata have stayed away from using mastic asphalt covers after the national green tribunal (NGT) had banned asphalt baking by the roadside in October 2018.
The new German technology will ensure that a mastic asphalt plant in Rajarhat has zero emission while churning out “mechanised mastic asphalt” that will last longer and offer a better ride-quality on roads where it is used.
The PWD is using this asphalt to repair certain roads in Kolkata that are under its jurisdiction, including Red Road. “We will go into a rate contract with the PWD and then start redoing the roads. It can’t be an excuse for us that the sand below the roads keep shifting due to seepage of water leaving the roads with undulating surfaces,” Hakim said.
Senior officials said among the stretches that engineers have identified for repair include the one between Hazra and Tollygunge Club. “Water appears to be leaking underground from the pipes connecting to the Kalighat pumping station,” said an engineer of the roads department. “We have decided that all the pipes under this stretch would be completely jacketed.”
Officers of the cash-strapped KMC said they have of late been witnessing a trickle of revenue prompting the planners to take up road repairs on priority basis. The repairs would be stopped with the onset of monsoons and then taken up again, ahead of the Pujas, officials said.
Besides the mix of sifting sand and alluvial soil underneath the road surface, engineers also blamed the practice of cutting trenches for either immediate repairs or maintaining underground utilities.
Once the job is done, these trenches are covered with a layer of asphalt which results in uneven surfaces, engineers said.