Contract includes 24km of new motorway around Newport and 2.5km viaduct
A Costain and Vinci joint venture has been appointed by the Welsh government to provide design development for the £750m M4 corridor around Newport.
The proposals would include 24km of new motorway and a 2.5km long cable-stayed viaduct crossing of the River Usk, as well as major remodelling of M4 junctions 23 and 29.
The joint venture includes Costain, which has a 50% stake, Vinci Construction Grands Projets and Taylor Woodrow.
Scheme development work will start immediately, leading up to an anticipated public local inquiry in winter 2016/7. Construction could start in spring 2018.