The new ‘dumbbell’ layout at Mile End in Oswestry will enable A5 traffic to bypass the main roundabout via a new island 75 metres to the north east.
Funded by a £9.3 million grant from the Government’s Housing Infrastructure Fund, Shropshire Council says the work will increase capacity on the A5, enabling future housing and employment developments around Oswestry to be constructed.
The island was rebuilt at a cost of £4m in 2014 and the road markings had to be redrawn in 2018 after complaints that the roundabout's layout was confusing.
The layout of the A483, which merges into the A5, was also altered at nearby Maesbury Road in 2018.
Under the new design, traffic travelling from Shrewsbury towards North Wales will leave the A5 on the approach to Oswestry, go over the new roundabout and continue onto the A5/A483 northbound.
A service road linking the two roundabouts will be created using the existing stub arm exit off Mile End, and the current A5 northbound exit off Mile End will be closed off.
Traffic from Oswestry and Mid Wales will need to go over both roundabouts if travelling towards Shrewsbury or north Wales.
It comes after plans for 600 new homes were approved for land next to the roundabout, behind the leisure centre on Shrewsbury Road.
The new roundabout will also provide future access to the proposed Oswestry Innovation Park.
Highways England has supported the scheme, which it said would reduce journey times on the A483 and queuing at the roundabout despite acknowledging it would have a knock-on effect on other parts of the road network.
Highways England said: “Notwithstanding these benefits we note that it is a consequence of the scheme that journey times on the A5 northbound from Mile End to Whittington are shown to increase together with queues on the A5 northbound approach to the Whittington Roundabout.
“These impacts arise from the pass through of traffic previously ‘bottled up’ at the A5 Mile End junction.”
A report by planning officer Philip Mullineux said: “On balance this application is considered acceptable and will contribute towards future housing and economic growth in the Oswestry area and thus is considered necessary and welcome in relation to satisfactory infrastructure development and the overall aims in relation to the application.
“On balance the development is considered to be in accordance with the local plan and the National Planning Policy Framework and as such the recommendation is one of approval subject to conditions.”