An underground pipe network in Salt Lake’s JD block sprang four leaks, triggering water crisis in at least seven blocks.

At least two large puddles and several smaller ones have formed near the SN Bose National Centre for Basic Sciences campus because of the leaks.

An engineer of the Bidhannagar Municipal Corporation said on Sunday water was leaking from a joint where several pipes meet. The pipes carry water from tank number 13 to IA, IB, IC, JC, JD, KB, KC and some other blocks in Sector III.

“The pipes are joined with an ordinary lead joint that cannot endure high water pressure and tend to rupture frequently,” the engineer said.

Another leak has developed under the Amul Island on Broadway, which connects Salt Lake with the EM Bypass.

Indranil Chakraborty, a resident of IB block, said they had been facing water shortage over the past several days. “The supply has reduced to a trickle and the water tank at our house barely gets filled,” Chakraborty said.

A resident of IC block, Sandeep Kumar Jha, said the crisis was forcing them to buy water. “We are storing as many bucketfuls of water as possible but still I have to buy water,” Jha said.

Another engineer of the Salt Lake civic body said all the joints in the underground water network would be replaced with mechanical joints that would have steel gaskets and bolts to withstand high water pressure.

“These joints last longer and don’t rupture frequently.... The pipes need to be replaced, too, because they are quite old and have weakened,” the engineer said.

Water pipes being replaced in the township. Picture by Gautam Bose

The Bidhannagar Municipal Corporation has started overhauling and cleaning water pipes in Salt Lake to prevent leaks and wastage. But the existing network, which was laid when the township was being built, has weakened with age.

“The sediment deposits inside the pipes have reduced their capacity to a large extent and weakened them considerably,” the engineer said.

Salt Lake is supposed to receive close to eight million gallons of water every day from the treatment plant in New Town. But the township is not getting that volume because of inadequate infrastructure.

The Calcutta Metropolitan Development Authority is laying a network of pipelines across Salt Lake to ensure that it gets adequate supply. The new pipes are made of high-density polyethylene — a synthetic material that is not prone to leaks.

Birendranath Biswas, the mayoral council member in the Bidhannagar Municipal Corporation in charge of water supply, said the leaks would be repaired soon.

Ten days ago, the main water pipe that distributes water from Tank No. 10 to the EE and ED blocks near the Karunamoyee bus terminus had ruptured in at least two places. More than 1,800 houses had to go without water till it was repaired by a Calcutta Municipal Corporation team.