Bridge design error delays bypass opening by a year

The cost of the delay could be as much as £20m

An error in the design of a bridge has delayed a major bypass project by at least a year.

Lincolnshire County Council said a planned 400m bridge on the Grantham Southern Relief Road has had to be changed because its designers had not accounted for wind during its assembly.

The bypass was due to be finished this year but now it will not be completed until 2026.

The council said it anticipated the mistake would cost up to £20m, "but we will be recouping that".

Sam Edwards and Richard Davies say the council will work to recoup the money

Bridges are usually put in place using cranes, but because the bridge in question crosses the East Coast Mainline and the River Witham it will be "pushed into place in sections", said Richard Davies, executive member for highways at the council.

"The concern was that as wind blew across it, it could cause it to flex and move out of alignment while it's being pushed across," he said.

"That would be really difficult to correct because the full deck weighs 2,600 tonnes.

"We've had to go back to the drawing board – or the designers have after recognising that they'd made a mistake. This means they're liable and there will be a case for them to answer."

'We'll get our money back'

Fixing the error is expected to cost between £10 and £20m, taking the predicted full cost of the bypass to between £158m and £168m.

Sam Edwards, head of highways infrastructure at the council, said he shared "the public's frustration" at the delay.

"We employed a global expert, so we feel really let down by that process," he said.

"But we need to focus on delivering the bridge and hold to account those that need to be held to account to bring that money back to the taxpayer."

Davies added: "I'm very frustrated and disappointed that we've been let down by the professionals we employed to do this work but I'm confident we'll get our money back."

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