There has been a contraflow in place on the A45 between Rushden and Wellingborough since February to allow Network Rail to demolish a bridge as part of the rail line upgrade.
The demolition of the old bridge had been planned for this weekend but Network Rail had planned to keep a contraflow system in place while the work was carried out.
But the rail company announced at the last minute that Westbound traffic would now not be able to use the road all weekend for safety reasons, and that instead a diversion would be in place.
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This room shoppers and weekend drivers by surprise and traffic has been gridlocked all morning. They said no signs had been in place around the site and so they did not know the work was due to take place.
A Network Rail statement said: “Network Rail is saying sorry to motorists who will be affected by the extension of roadworks on Higham Road bridge, near Wellingborough.
The section of the bridge needs to be raised to allow for the safe clearance of overhead line equipment in anticipation of electrification of the route between London to Kettering and Corby via Bedford.
“To allow the work to take place safely, a section of the westbound section of the A45 has been closed since Monday 4 February 2019.
”This weekend the old bridge deck will be demolished, which means there will only be access through the contraflow for eastbound traffic. Westbound drivers will need to follow the signed diversion. The changes to the road are needed to make sure that passing motorists are kept a safe distance from the demolition work. The westbound contraflow will reopen at 6am on Monday morning.”
Network Rail Sponsor, Gavin Crook said: “We are sorry for the extra disruption which will be caused and for the short notice that the contraflow needs to be amended this weekend.
“We are working closely with Highways England to keep disruption to a minimum and our work remains on schedule.”