Temporary speed limits of 50 mph, 40 mph, or 10 mph will also be enforced on the roads. The closure extends from the Coldra Interchange in Newport (M4 Junction 24) to the centre-point of the A449/A40 Raglan Interchange in Monmouthshire. Non-motorway northbound vehicles will be redirected via the westbound A48 Southern Distributor Road to Grove Park Roundabout, A4042 to Hardwick Roundabout, and eastbound A40 to Raglan Interchange. The northbound and southbound exit and entry slip roads at Usk Interchange and Raglan Interchange will also be closed. The temporary traffic prohibitions and restrictions are expected to operate intermittently overnight for a maximum duration of 18 months.