It is race against time for the one of the longest river bridges in the world, the Mahatma Gandhi Setu connecting Patna with in North Bihar. The 7.5 km long bridge commissioned in 1982 is under severe stress due to the Ganga’s changing course and obsolete design. The wear and tear now threatens human life.
The traffic on the western flank was stopped long back following serious damage to several piers due to de-stressing. Before it could be repaired, the eastern flank has also developed similar problems due to mounting traffic load. The bridge takes over 35000 commercial vehicles a day generating close to Rs one crore revenue.
Amidst fear that the vital link may be snapped, the Bihar government has finally decided to start extensive repair of the roadbridge on its own. “We have sent a detailed proposal to the Centre in this regard, but the sanction of funds is still awaited. We, however, can’t wait anymore,” said Road Construction secretary RK Singh.
Singh, however, said that the proposal had been cleared in principle. “The authorities in the Ministry of Surface and Road Transport have assured us of approval. But we will start work straightaway in view of the urgency,” he said, admitting that several cantilevers in the bridge had developed cracks or gaps.
Built with the pre-stress technology by Gammon India and inaugurated in 1982 by former Prime Minister Indira Gandhi, the bridge developed snags barely in two decades.
The repair was estimated to cost Rs 34 crore in 2004, but now due to problems in both the flanks and almost all the piers, it may go up to Rs 110 crore, said a senior enginner working on the site.
Chief Engineer, National Highways, SD Ram said all the bridges built with this technology had reported similar problems worlwide due to “loss of stress” after certain time span.
“External pre-stressing is the only solution to prolong the life of the bridge. The consultants had earlier suggested external pre-stressing all along the upstream side,” he added.
The Road Construction Secretary said external pre-stressing had been done on two spams, while work was on four others. It costs Rs 1.25 crore per spam and the bridge has 45 spams on each side.
“In January, we found out that nine more spams required pre-stressing. Besides, 33 more hinge bearings need to be changed. Earlier, order had ben placed for 13 hinge bearings. Replacement of more hinges may be required as the repair begins,” he added.