Features

The Highways Agency project to improve safety and cut congestion on the A421 in Bedfordshire between Bedford and the M1 takes another significant step forward in September, when work to place the beams on the new bridge over the M1 will be carried out.

This phase of work, which starts on Monday 14 September, involves lifting the steel bridge beams into place. It will require a series of nightly closures of the motorway between junctions 13 and 14, in one direction at a time only so as to limit any delays for road users.

Construction of the new bridge has been underway since January and the abutments and central pier are now in place. Once completed, the bridge will carry the widened A421 over the motorway as part of the improvements at this busy junction. So far the work has been carried out mostly overnight, with lane closures in place to ensure the safety of the workforce and the travelling public.

Roy Brunsden, Project Manager for the Highways Agency, said:

“Construction work is progressing well and we have now completed as much as we can without closing the motorway to traffic. The abutments and central pier are in place and next we need to place the bridge beams above the M1.

“The beams are in pairs and vary in length from 26m to 37m, with a paired weight of 25 to 40 tonnes. This means we’ll need to use a 250 tonne capacity crane to lift and position them. Once that is done we’ll be casting a concrete slab over the beams, using 400 cubic metres of concrete, which will eventually support the new A421 dual carriageway.

“This work can only be done when the road is closed. However we will carry out the work in stages, meaning we only have to close the motorway overnight in one direction at a time and when traffic is at its lightest.

“The short diversion route will be clearly signposted and we ask drivers to be patient, to approach this section of the M1 with extra care and allow more time for their journey.”

First, the southbound carriageway will be closed for three nights:

·       9pm to 5am nightly from Monday 14 September to Thursday 17 September

The northbound carriageway will then be closed for three nights:

·       9pm on Friday 18 September to 7am on Saturday 19 September

·       9pm on Saturday 19 September to 9am on Sunday 20 September

·       10pm on Sunday 20 September to 5am on Monday 21 September

Southbound traffic will be diverted off the motorway at J14 and use the A509 towards Milton Keynes, the A4146 and the A421, before rejoining at J13. Northbound traffic will follow the same route in reverse.

The A421-M1 project involves building a new eight-mile stretch of dual carriageway on the northwest (Wootton) side of the existing A421, improvements to Junction 13 of the M1 and the construction of new two-level junctions at Marston Moretaine and Marsh Leys. To further improve safety for road users and road workers, and provide more reliable journey times during the work, average speed safety cameras came into operation in July.

The scheme, which is due to be completed by December 2010, will provide a safer and less congested route between the motorway and Bedford Southern Bypass. The majority of the new road is being built parallel to the existing A421 so as to limit any delays to traffic.