Gloucestershire County Council is calling on utility companies to help keep traffic moving during major works on the A40 Over Bridge.
National Highways will carry out essential repair and maintenance work on the bridge from June 8 until spring 2027.
The bridge spans the River Severn and connects Gloucester, Cheltenham and Ross-on-Wye, with around 5,000 vehicles an hour using it at peak times.
The county council has written to utility companies urging them to avoid non-essential works that could add to congestion.
Its Streetworks Team will also assess permit applications in the area case by case.
Drivers are being urged to plan ahead and consider alternative routes, especially during peak times.