Important guidance for wide load vehicles:
Lane width restrictions in place on the M4 between J47 Penllergaer to J49 Pont Abraham during the ongoing bridge deck refurbishment works.
If you operate a vehicle that is both wide and long, it is essential that you follow the instructions below for safety.
Due to the contraflow system, there are restrictions on the size of vehicles that can pass using the lanes.
Vehicles with a width under 2.9 metres can use the contraflow system.
Vehicles with a width between 2.9 metres - 3.6 metres and a length under 16.5 metres can use the diversion route through Loughor.
Vehicles wider than 2.9 metres and longer than 16.5 metres must obtain permission from the South Wales Trunk Road Agency before undertaking their journey, as they may not be able to pass safely.
- Lane 1: maximum width allowance - 2.9 metres
- Lane 2: maximum width allowance - 2.5 metres
- Wide vehicles cannot straddle eastbound lanes due to a physical barrier between lane 1 and 2.
There will be no restriction on the westbound during this time.
• Lane 1: maximum width allowance - 2.9 metres
• Lane 2: maximum width allowance - 2.5 metres
• Wide vehicles cannot straddle westbound lanes due to a physical barrier between lanes 1 and 2.
There will be no restriction on the eastbound during this time.
If you have not gained advanced permission to travel and your vehicle is either:
- 2.9 meters to 3.6 meters wide, and longer than 16.5 meters;
- or over 3.6 meters wide
you will be directed as follows:
Westbound: Leave the motorway at M4 J32, park at the South Wales Traffic Management Centre, and contact 0300 123 1213 for further guidance. Vehicles that join the M4 after J32 will be asked to return to M4 J32.
Eastbound: Park at lay-by on the A40, located immediately after Tenby Road Filling Station, and contact 0300 123 1213 for further guidance. Vehicles that join the carriageway after passing this lay-by, may briefly park at the lay-by on the A48 approach to Pont Abraham Interchange Junction to contact 0300 123 1213 for further guidance.