Two new bridges are being built over Tolly’s Nullah to ease traffic on Tollygunge bridge and Durgapur bridge, mayor Firhad Hakim said on Wednesday.

Traffic on the two existing bridges has increased manifold since the collapse of the Majerhat bridge in September.

The bridges being built will help commuters from Behala and New Alipore, giving them more travel options, and also distribute the traffic among the four routes, an engineer of the Calcutta Metropolitan Development Authority (CMDA) said.

“We are building two bridges in Tollygunge. All those evicted to make way for the bridges will be rehabilitated,” Hakim said.

Metro had reported on October 26, 2018, about the government’s plan to build the two bridges.

The piling work for one of the bridges has been completed and for another is underway.

Sources in the CMDA, the implementing agency for the project, said on Wednesday that both the bridges would be short.

A 40m-long bridge would cross Tolly’s Nullah from MG Road in Tollygunge Karunamoyee. Vehicles from MG Road will take the bridge and travel on a yet-to-be-built road to reach Mahanayak Uttam Kumar Sarani, which leads to Tollygunge Metro station, a little north of the existing Karunamoyee bridge.

“This would help vehicles bypass the traffic signal at the Karunamoyee crossing, which remains congested during rush hours,” a CMDA engineer said.

The bridge will be 6.9m wide, including the pavement. The carriageway will be 5.5m wide.

A 26m-long bridge is being built near the northern boundary of Tolly Club.

It will take vehicles on BL Saha Road in New Alipore to Deshapran Sashmal Road, a little south of the Tollygunge Phanri crossing.

The width of this bridge will be 8.9m and it will have a 7.5m-wide carriageway.

“A short road will take vehicles that cross the bridge over Tolly’s Nullah to Deshapran Sashmal Road,” said the engineer. “We will need to take some land from Tolly Club for both the connecting roads.”

It will take around four months for the bridges to be built.