Structural engineers running stress tests on the damaged Marlow Bridge have ordered a river barge to allow work to continue below the road deck.

Previous inspections found seven areas of concern on the bridge - which has been closed to traffic since a 37-tonne HGV tried to cross it on September 24 - and now more "focused" tests are needed. 

The next tests will find out if some of the suspension hangers need replacing and bare steel will need to be exposed.

Above the road deck engineers are building an access platform, but below the deck a river barge has been requested to allow more intense testing of the highlighted areas on underside of the bridge.

Contract manager, Simon Dando, said these more focused tests could only be carried out by removing decades of paintwork from the suspension bridge's metalwork. 

Engineers are working with the Environment Agency to cordon off a safety exclusion zone around the barge, which will be used in the week beginning October 31.

They will analyse their findings during the first week in November and if they recommend replacing sections of the bridge, specially manufactured parts could take up to 12 weeks to make and a further eight weeks to install.

Mark Shaw, Bucks County Council cabinet member for transport, said: "We're taking the utmost care with our testing, which I know is exactly what residents and businesspeople in Marlow and Bisham would expect of us.

"I'm sorry that we need to close the bridge to vehicles, but the risks to engineers' safety, not to mention the potential of additional damage to the structure, make it imperative that we keep it clear of traffic until we know the extent of damage and what repairs are needed."