Work will begin this evening to renovate and upgrade the iconic Oakland Bay Bridge in the San Francisco Bay, to make it earthquake-proof.
The vast £3.8bn ($6.2bn) project will begin with a bridge shunt over the coming weekend (the Labor Day weekend - a major holiday in the US).
California Department of Transportation (Caltrans) spokesman Bart Ney said: “It’s a rare opportunity.”
Under modelling, the eastern section of ther bridge has been shown to be prone to collapse if a large earthquake hits San Francisco.
As this section cannot be retrofitted, a replacement viaduct has been constructed to replace the old section.
The iconic western section has been shown to be more robust, although it has undergone significant retrofitting of rivets and modifications have been made to bridge piers.
Over the coming weekend, aerial bridge workers will cut-out 100m of double deck roadway on the east side while teams of painters, potholers, electricians, tree-pruners and sign hangers will get to work on the west - avoiding San Francisco Fire Department’s rescue drills which have been scheduled to coincide with the renovation work.
The bridge will replace the cut-out section with a prefabricated detour to let traffic back over until the bridge fully reopens in 2013.