Temporary Speed Limit on M4 in South Wales: What You Need to Know

The Welsh Government is introducing a temporary speed limit on certain sections of the M4 motorway in South Wales. This change is due to essential roadworks planned in the area. Here's a breakdown of what drivers need to know:

Key Details:

• Speed Limit: A temporary speed limit of 40 miles per hour (mph) will be enforced.
• Effective Date: The order comes into effect on 14th July 2025.
• Duration: The order will be in place for a maximum of 18 months, but specific sections have their own timelines.

Affected Sections:

1. Junction 30 (Cardiff Gate, Pontprennau) to Junction 33 (Cardiff West)
   • Period: From 00:01 on 14th July 2025 to 23:59 on 8th August 2025.
2. Junction 23A (Magor, Monmouthshire) to Junction 26 (Malpas, Newport)
   • Period: From 00:01 on 11th August 2025 to 23:59 on 3rd September 2025.

Exemptions:

Certain vehicles are exempt from this speed limit, including:

• Vehicles used for military purposes, when driven by personnel undergoing training or responding to a national security emergency.
• Vehicles performing specific functions as outlined in Section 87 of the Road Traffic Regulation Act 1984.

Implementation:

The speed limit will only be enforced during times indicated by traffic signs along the motorway. Existing speed restrictions will be temporarily suspended when the new limit is active.

Purpose:

The temporary speed limit is necessary to ensure safety during roadworks on these sections of the M4, which is a critical route connecting London to South Wales.

For the latest updates and traffic management information, motorists are encouraged to monitor local traffic reports or consult the Welsh Government's transport department.

Stay informed and drive safely to ensure a smooth journey through these areas while improvements are underway.