Improvement works are due to begin on the A26 Moira Road, Glenavy, today.
The £435,000 project will include raising the headroom clearance on the footbridge to improve safety for pedestrians and a resurfacing scheme along a 1.1km stretch of the road.
A road closure will be in operation overnight from 9pm on Saturday 30 June to 9am on Sunday 1 July to facilitate removal of the bridge.
The improved structure will be replaced in late summer when final resurfacing work will also be completed.
Work has been planned to minimise disruption to the public however a temporary 40mph speed limit will be in operation from 1 July until 2 September.
A temporary crossing point will also be provided to help pedestrians cross the road safely.
Throughout the period when the footbridge is removed, pedestrians should exercise extra care and attention if they need to cross the main A26 Moira Road. Motorists should also allow extra time for their journeys particularly if travelling to the airport.
The Department would like to apologise in advance for any inconvenience that the works may cause and thank the public and local residents for their patience while this work is carried out.