The new permanent average speed cameras on the A338 Bournemouth Spur Road, will go live on Friday 31 May 2019.
They will support a temporary 40mph speed limit on the southbound carriageway of the A338 from Blackwater Junction to the Cooper Dean Roundabout.
The 40mph southbound limit will be in place for the remainder of the works and the cameras will support a 50mph limit on the northbound carriageway.
Following the completion of the scheme next month, average speed cameras will support the 50mph limit that was previously in place on both sides of the carriageway, managed by Dorset Police.
Gary Powell, the senior responsible officer for the A338 improvements, said: “The cameras will help make the Blackwater slip roads easier and safer to use as motorists travel at a consistent speed through the area. They will also help improve the flow of traffic.
“We would like to remind motorists to follow the speed limit and be mindful that the speed cameras will become operational at the end of the month. These are in place for the safety of our operatives who are working during the day, at night and at weekends to complete the improvements as soon as possible.’
Currently, work on the multi-million pound A338 / Blackwater Junction Improvements scheme is running to schedule for completion at the end of June. Until near the end of the scheme, there will be a series of overnight road closures to enable surfacing and barrier installation works to be carried out. There will be no overnight closures over the coming May bank holiday weekend.