Remotely operated vehicles to assess sea link health

The vehicles, to be deployed over the next four months, will transmit high-definition videos of submerged portions of the bridge

Mumbai: Sixteen years after it was inaugurated, the health of the iconic 4.7-km Bandra Worli Sea Link (BWSL) will be assessed using submersible remotely operated vehicles. The vehicles, to be deployed over the next four months, will transmit high-definition videos of submerged portions of the bridge that will help identify defects and cracks and initiate work on repairs, said officials from Maharashtra State Road Development Corporation (MSRDC), which owns and maintains the structure.

The Bandra Worli Sea Link has 179 foundation piers, each supported by a number of piles based on the thickness and placement of the pier (Hindustan Times)

“This is the first time that submersible remotely operated vehicles will be used to inspect the Bandra Worli Sea Link,” said an MSRDC official. Scuba divers had been deployed to remove marine growth and inspect the bridge earlier, and they are likely to be deployed this time too, to remove any marine growth on the structure prior to inspection.

Work on the sea link commenced in 2000, nine years before it was formally inaugurated in June 2009. It has 179 foundation piers, each supported by a number of piles based on the thickness and placement of the pier. The scrutiny over the next four months will involve inspection of the underwater piers and piles, non-destructive testing, scour survey and underwater ultrasonic thickness measurement for steel, said officials.

Non-destructive testing analyses properties of materials used in construction while underwater visual inspection helps identify defects, cracks and cavities. Scour survey involves monitoring of offshore structures to prevent any disasters; in case of the sea link, it will involve removal of sediments such as gravel or sand from the base of the foundation pillars.

“The remotely operated vehicles will transmit high-definition live videos of submerged portions of the bridge. If any defects are identified, they will be geo-tagged,” said the official.

The inspection will help identify the need or urgency for repairs or replacement/ reconstruction of portions of substructures, the official noted, adding, “Following the survey, suitable rehabilitation as well as repair works will be undertaken.”