Highways England is carrying out a maintenance scheme at the viaduct near Gloucester, which will maintain the integrity of the structure and avoid more costly repairs in the future.
Work including, replacing worn out joints waterproofing and resurfacing, will start on Monday June 22 and continue until mid-September.
Project sponsor Mike Webster said:
We appreciate that the A40 is a vital link between the Forest of Dean and Gloucester and that is why we have done everything we can to minimise the delays by installing a traffic management system that takes in to account traffic flows at different times of the day.
In the morning there is far more traffic travelling east and in the afternoon far more traffic travelling west and our road closures reflect these variations to ensure as few people as possible are inconvenienced.
We have also worked with Gloucestershire County Council to ensure our works are being co-ordinated with schemes they are carrying out in the area and we will be keeping our customers updated as the scheme progresses.
Work will take place on a 1.3 mile section of the A40 between Longford Roundabout and Over Roundabout and will require road closures in order to ensure work can be carried out safely.
From 12am until 12:00pm, 7 days a week, the Longford roundabout to Over roundabout link will be closed to westbound traffic. This closure will then switch to the opposite direction, eastbound, for the remainder of the day. It is because there is far more traffic travelling east in the morning and west in the afternoon, that we have designed our traffic management so as to inconvenience as few people as possible.
During the closures fully signed diversion routes will be in place.
Drivers travelling eastbound between 12pm and 12am will be diverted south onto the A417, then onto the A430 before being directed on to Cole Avenue, then Finlay Road and the A38/Eastern Avenue. Drivers will then continue on to Corinium Avenue, north on the A417 and re-join the A40 at Elmbridge Court roundabout. West bound traffic will follow this in reverse.
No significant traffic delays are expected but drivers are advised to allow an extra 10 minutes to complete their journeys.
Members of the public should contact the Highways Agency Information Line on 0300 123 5000.
Journalists should contact the Highways Agency press office on 0844 693 1448 and use the menu to speak to the most appropriate press officer.