The state government has installed 32 CCTV cameras on the Tallah bridge to keep round-the-clock vigil on the distressed structure, which engineers want demolished.

“The CCTV cameras have been installed to maintain a 24X7 surveillance on the bridge. The government wants to prevent any sudden collapse, which can lead to loss of lives. If the cameras catch any warning sign, there could be a blanket ban on vehicular movement on the bridge,” a government official said.

Buses, trucks and other heavy vehicles are no longer allowed on the north Calcutta bridge. Cars and other small vehicles are allowed but their speed cannot exceed 10kmph.

The official said the cameras were installed during the Puja at a cost of Rs 22 lakh.

The 57-year-old bridge has become a bother for the government since RITES, an engineering consultancy, advised its demolition.

Sources said officials of the PWD and the railways had been given access to the footage of the cameras. No monitoring camp has been set up because the footage can be seen anywhere on an Internet-enabled device.

“PWD engineers experienced in bridge upkeep are constantly monitoring the structure. Railways officials have said they, too, are maintaining a vigil,” said an official.

A major part of the Tallah bridge runs over railway tracks.

The cameras, officials said, were installed to ensure that all agencies associated with the bridge got real-time updates on the condition of the ailing structure.

“The PWD wants to monitor whether cracks are widening, fresh cracks are appearing or concrete chunks are coming off the structure. Such signs could be indicative of an imminent collapse. If such signs are spotted, the state government will stop all vehicular movement on the bridge,” a PWD official said.

A section of officials, however, claimed it was difficult to predict a collapse based on CCTV footage.

“Usually, such structures collapse without sending a signal…. Even if there is a signal such as widening of cracks, the authorities hardly get any time to take effective measures,” an engineer said.

Some PWD officials think it is almost impossible to monitor the bridge 24X7. “There are not enough personnel for the job,” an official said.