M4 ‘Progress Update’ published

Published 14/01/2020   |   Last Updated 27/05/2021   |   Reading Time minutes

Following the First Minister’s decision in June 2019 not to proceed with the M4 relief road, the Welsh Government set up the South East Wales Transport Commission. In December 2019 the Commission published an update on its progress, ahead of its interim report in the spring and its final report, which is planned for the end of 2020.

Our previous blog post outlined the background and some initial reactions to the decision not to build the M4 relief road ahead of a Welsh Government debate on 25 June 2019.

What is the Commission’s role?

On 5 June the Minister for Economy and Transport, Ken Skates AM, outlined the remit of the South East Wales Transport Commission:

The Commission will look at the extensive work the Government has done on this, at the alternatives proposed in the M4 Project Public Inquiry, and will also look at new ways of operating and funding a solution. This will require new ways of working with local and strategic partners…to deliver improved flow on the M4 whilst mitigating impacts on local communities.

The Minister also outlined initial actions that the Welsh Government would be taking immediately, including additional traffic officers to reduce incidents and lane closures.

The Commission’s terms of reference were also published on 5 June. On 2 October the Minister announced the seven Commissioners who had been appointed with Lord Terry Burns as the Chair.

The Commission published ‘Our Approach’ on 16 October, which outlined the actions it aims to take to in developing its recommendations to reduce congestion. Eight principles were agreed by the Commission to guide its work, including to:

  • Approach the problem afresh, considering the root causes of congestion;
  • Explore options across all forms of transport, including integration between different modes;
  • Not limit itself to the conclusions of previous studies of the problem; and
  • Involve a diverse range of people in its work, including those that live, work, commute or have an interest in the area.

The document also made clear that one of the Commissioners, Beverly Owen, is included as a ‘Newport Representative’ to ‘[reflect] the particular impact of the issues on the city of Newport’. She will have access to the Commission’s work and be involved in discussions, but will not be involved in decision-making.

Three quick wins

On 17 December the Commission published a ‘Progress Update’ with ‘fast-track’ measures that the Welsh Government had tasked it to provide.

The report outlines the Commission’s findings so far. It highlights that:

Existing demand is some 1,000 to 1,500 vehicles [per hour] above the level required for reliable journeys. This provides us with a sense of scale to what change might be required to alleviate congestion.

In the report the Commission identifies areas where it may make future recommendations. These include public transport improvements to give people more choices when travelling between Cardiff, Newport and Bristol, road improvements, land use policies and transport planning, as well as steps to integrate different modes of transport for more flexible journeys.

The Commission suggests three specific measures that it recommends the Welsh Government implement quickly as a package, at a capital cost of about £1-2 million:

  1. Replace the variable speed limit from junction 24 (Coldra) and up to junction 28 (Tredegar Park) with a 50mph speed control;
  2. Provide additional lane guidance on the westbound approach to the Brynglas tunnels and use physical interventions to prevent late lane changes; and
  3. Enhance traffic officer support with response time targets and extend patrols to the A48 and A4810 in Newport.

The Commission makes it clear that it does ‘not pretend these measures will resolve congestion entirely’, rather their purpose is to provide ‘fast-track’ recommendations to improve traffic flow and journey times in the short-term. It says these shouldn’t pre-judge or negatively affect the final conclusions. The Commission highlights that this report comes a couple of months after its establishment and emphasises that the report ‘contains only limited findings and initial recommendations’.

50mph speed control

There are currently 50mph speed limits on the motorway between junction 25 and junction 26, which are intended to improve air quality. The Commission recommended that these should be extended further along the M4.

The Commission’s analysis suggests that an average speed control helps improve the regularity of traffic by encouraging drivers to travel at a more consistent speed. The analysis also shows 50mph to be the optimal speed in terms of journey time but also air quality and noise. It says this should be enforced through regularly placed speed cameras to ensure compliance throughout the whole control section.

Lane guidance

The Commission found that late lane changes contribute to a breakdown of traffic flow on the M4. This is particularly felt at junction 25a on the approach to the Brynglas tunnels where the motorway drops to two lanes.

The Commission is recommending that the white line lane markings should be longer to effectively lengthen the slip road, so it’s further away from the tunnels. It would like to see the use of collapsible bollards to move drivers into the correct lanes earlier to prevent late lane changes. The road numbers should also be clearly marked on each of the lanes. Figures 1 and 2 below illustrate the issues raised in the report.

Figure 1: the ‘ripple effect’ of late lane changes.

Ceir ar y ffordd Source: South East Wales Transport Commission: ‘Progress Update’

Figure 2: the lane guidance changes recommended by the Commission

Ceir ar y fforddSource: South East Wales Transport Commission: ‘Progress Update’

Traffic officer support

After the M4 decision was made the Welsh Government brought in additional traffic measures, including extra traffic officers.

The Commission recommends that the Government build on this by bringing in response time targets for officers to reach an incident. It also suggests that traffic officer equipment be reviewed to ensure the officers are carrying the best tools to resolve incidents.

What’s the next stop?

In Plenary on 26 November the First Minister said, referring to the update report, that:

[The Commission] will produce their most immediately available actions…I certainly don’t want to wait for those ideas to be implemented until further parts in the reporting process….we will certainly not wish to hold up anything that we can get on with as fast as we are able to.

The Commission aims to publish an interim report this Spring and a final report by the end of 2020.

The Chair of the Commission, Lord Burns, will provide an update to the Assembly’s Economy, Infrastructure and Skills Committee on 6 February, which can be viewed on SeneddTV.


Article by Lucy Morgan, Senedd Research, National Assembly for Wales