HIGHWAYS England has had to apologise after delays clearing up a bridge demolition caused a day of chaos for motorists.

The old Merafield Bridge at Plympton was spectacularly blown up overnight last Saturday, with the A38, which was closed for the demolition between Deep Lane and Marsh Mills, scheduled to reopen at 9am on Sunday.

But due to ’technical difficulties’ with the clean-up operation the road, the main artery serving the South Hams, Plymouth and South Cornwall, remained closed for almost the entire day, with huge tailbacks in both directions.

Coinciding with one of the sunniest days of the year so far, motorists heading out were diverted through Plympton, which rapidly became gridlocked with frustrated drivers. Problems were further compounded by a vehicle fire and roadworks causing delays on the A379 between Brixton and Yealmpton.

The A38 finally reopened to westbound traffic at 4pm, with two eastbound lanes opening at 6.35pm. The dual carriageway remains in contraflow, with two lanes in each direction until work on the project is fully completed in July.

A new bridge, which was built alongside the old, was opened two weeks ago.

Highways England explained that parts of the old bridge were not fully broken up in the demolition, so work to break up and remove the bridge continued into Sunday afternoon.

Project lead Julian Strong said: ’We worked hard today to reopen the A38 as quickly as possible. The bridge was demolished successfully, but the work to break up and remove the debris took longer than expected.

’We are sorry for the disruption that drivers experienced today, and will be looking in detail into what happened that slowed this work down.

’The work we are doing to replace Merafield Bridge will help to ensure that journeys on the A38 - and Merafield Road over it – will stay safe and reliable for years to come, and keep unplanned maintenance to a minimum in the future.’

The new bridge has been under construction alongside the old for months, and was recently opened to traffic.

50 kilograms of explosives were used for the demolition, contained within 278 holes drilled mainly around the supporting piers and abutments at each end.

The new concrete bridge is 80 metres long, 11.3 metres wide and made of 2,503 tonnes of concrete and 401 tonnes of steel.

The demolition and clean up is one of the final stages in the £6.3million project. The scheme will be fully completed by July, with remaining work to include clearing away debris from the demolished structure, completing drainage on Merafield Road, finishing works on the new bridge and reinstating the road markings on the A38.

The old bridge was suffering from alkali silica reaction, commonly known as ’concrete cancer’ which would in time have rendered it unsafe.

Throughout the project, Highways England said timing of the work has been coordinated to avoid disruption during the South West’s busy holiday season.