The installation of the new bridge deck for the A1 junction improvement at Carpenter's Lodge, will mark a milestone for the project.

The road will be closed while it is lifted into place between 6pm on Saturday August 30 and midday on Sunday August 31 as part of ongoing works to improve one of the busiest stretches of the A1 in the country.

The bridge deck has been constructed separately to the concrete supports so work on both could be progressed at the same time. The deck will be moved just over 100 metres from its current location along the A1 to its permanent position.

When the bridge deck is being moved and installed the A1 will be closed to through traffic in both directions between the A43 at Stamford and the A47 at Wansford. Through traffic will be diverted along the A43 to Duddington and the A47 to rejoin the A1 at Wansford, or vice versa.

Click to see a Google map showing the A1 diversion.

Using a special vehicle, the bridge deck, which is some 30 metres long and weighing 650 tonnes, will be lifted and driven at walking pace along the A1. It will then be lowered on to already constructed and prepared bridge supports. The bridge is expected to be open to traffic in late 2008.

This work is part of the A1 Peterborough to Blyth Junction Improvement Scheme.

Highways Agency project leader Bill Birkett said: "This will be a real milestone for the scheme and road users and local residents will soon get a real sense of how the finished scheme will look.

"We recently carried out two similar operations further north at Colsterworth, both of which were very successful. We plan to emulate that success at Carpenter's Lodge.

"This approach to the construction of the bridge is particularly unusual as the more common method involves building the bridge supports, lifting pre-cast beams into place then constructing the deck on top. By building the deck off-site we have been able to construct both elements of the bridge in parallel, shortening the length of the construction period and minimising delays for road users.

"In order to move the deck into place safely and in the shortest possible time it is unfortunately necessary to close the A1 in both directions. We advise drivers to allow extra time for their journeys and familiarise themselves with the diversion route before travelling."

The Carpenter's Lodge junction improvement works consist of constructing a new two-level junction to replace the existing roundabout and widening and realigning the northbound off-slip road to Racecourse Road. The scheme is due for completion in early 2009.