The damaged Bagha Jatin flyover, closed for repairs since September last year, cannot be opened before May.

March was the earlier deadline for recommissioning the high road, a part of which — over the railway tracks — caved in on August 19 last year.

With the flyover blocked, people are being forced to use the Bagha Jatin level crossing that remains in the grip of snarls for most part of the day.

Sources said safety aspects have prompted Ircon International Limited, a central undertaking executing the project, not to allow traffic on the flyover in a hurry.

“We are proceeding in a meticulous way to prevent a repeat of the cave-in,” said the deputy general manager of Ircon, I.N. Chakrabarty.

He said all three agencies involved in the repairs — the railways, Ircon and the CMDA — have decided to go through the design before the casting is done. “Only after the three agencies approve of the design will the casting be done. This will eliminate the chances of flaws creeping into the design unnoticed,” Chakrabarty added.

The casting, with “readymade concrete”, will take a day. “After that, the concrete will take four weeks to settle down,” said an Ircon official.

Apart from carrying out the Rs 25-lakh repairs, Ircon will find out why the structure collapsed six years after it was built.

The flyover was closed to heavy vehicles immediately after the cave-in on August 19. “Only vehicles like cars and two-wheelers were allowed. But the collapse of a flyover under construction in Hyderabad on September 9 prompted the authorities to close the Bagha Jatin high road to traffic,” said an official.