The work, which begins on Friday 29 July and is expected to finish in the autumn, will involve repairing the bridge and resurfacing the road where the A12 crosses Maldon Road, Witham.
Work to the bridge will be carried out overnight between 8pm and 6am. During the day a contraflow and narrow lanes will be in use to allow both lanes to remain open during the day on the A12 in both directions. A temporary 40mph speed limit will be in place 24/7 for safety reasons due to the narrow lanes.
There will be some overnight closures on the A12 to install crossovers which will allow traffic to use the contraflow.
Geoff Chatfield, Project Manager at Highways England, said:
During the day, drivers will notice a difference as there will be narrow lanes and a reduced speed limit in place, but we are making sure there are two lanes open in both directions.
Throughout the scheme, there will be a speed limit in place, which will be enforced. The lower speed limit is necessary for driver’s safety and because of the narrow lanes.
There will be occasional overnight closures throughout the work; whenever a closure is in place there will be a clearly signed diversion route, with drivers diverted to the B1389 through Witham to rejoin the A12. Abnormal loads will have an alternative diversion route via the M25, M11, A11 and A14.
The work is dependent on suitable weather conditions, and dates may be subject to change.
Members of the public should contact the Highways England customer contact centre on 0300 123 5000.
Journalists should contact the Highways England press office on 0844 693 1448 and use the menu to speak to the most appropriate press officer.