Today sees Wales go to the polls for Senedd elections in a vote which could be pivotal for the future of infrastructure in the country, and Cardiff and the South Wales region in particular. In this article, which follows on from our article on investment in the Cardiff and the South Wales region, Ellen Williams, Rob Russell-Smith and Owen Watkins look at the impact which the election could have on two of the major infrastructure projects recommended in the recently-published ICE Manifesto for Infrastructure in Wales 2021: Prosperity, Growth and Jobs: (1) building the ‘black route’ M4 relief road, and (2) the electrification of Wales’ rail lines, including between Swansea and Cardiff, and Cardiff Crossrail light railway system.

Burges Salmon has been closely involved with many major infrastructure projects within the region already – including the previous iteration of the M4 relief road, the A465 ‘Heads of the Valleys’ as well as advising Transport for Wales (“TfW”) and the Welsh Government on the Wales and Cross Border franchise and South Wales Metro (including transfer of the Core Valley Lines railway network from Network Rail to TfW, and the installation of Amey/Keolis as its new infrastructure manager), so will be monitoring developments on this front closely.

M4 Relief Road

The M4 relief road is a key point of difference between the three main Welsh parties of Labour, Plaid Cymru and the Conservatives:

  • the leader of Welsh Labour and current First Minister, Mark Drakeford, declined to back the M4 relief road in 2019, citing economic and ecological reasons, and the Labour Senedd 2021 manifesto confirms this position;
  • Plaid Cymru has historically opposed the relief road and sets out in its 2021 manifesto to instead “improve the mainline rail services in the south involving the building of six new stations between Severn Tunnel Junction and Cardiff”; and
  • recently the UK Prime Minister Boris Johnson and Welsh Conservative Party leader Andrew RT Davies have both promised to reverse Labour’s decision (articles here and here respectively) and in its 2021 manifesto, the Welsh Conservatives have promised to “create modern infrastructure for Wales, including an M4 Relief Road, upgrades to the A55 and A40 …”.

Despite these differences, there is likely to be significant pressure placed on whoever wins the election to push ahead with the relief road in some form, or pursue one of the alternative options proposed in the South East Wales Transport Commission’s latest report. The Inspector’s Report on the M4 Corridor Around Newport, issued in 2018 (known as the Burns Report), overwhelmingly backed the M4 relief road, concluding “there is a compelling case for the scheme to be implemented in order relieve an acute problem on the strategic motorway network … the scheme is in the public interest … and should be allowed to proceed…” . There is little to suggest this position has changed, although funding remains a key hurdle to overcome if the project is to go ahead (the spiralling cost of the scheme was a key factor in Mark Drakeford’s decision to bring previous efforts to a halt). ICE Wales Cymru’s report suggests greater collaboration between the Welsh and UK Governments may be the way to ‘unlock’ this issue given that investment in the scheme will benefit both Welsh and English regions. Other solutions include use of Wales’ ‘MIM’ model which we have seen used to bring forward other road projects in the country.

Railway Electrification

The electrification of the railway between Swansea and Cardiff was scrapped in 2017 by then Prime Minister Teresa May and Transport Secretary Chris Grayling. However, there is now increasing pressure to reconsider this decision:

  • ICE Wales Cymru has now called for a “robust and resilient transport network … Improved connectivity and capacity of road and rail links with London, southwest England, the Midlands and northwest England” to “drive economic growth within Wales”;
  • at the Welsh Affairs Committee Formal meeting: Railway Infrastructure in Wales on 11 February 2021, Great Western Railway’s Mark Hopwood called for electrification of this section of railway for both environmental and timetable benefits, and also backed the regeneration of Cardiff’s Central Train Station; and
  • the Welsh Government has opened (until 8 June 2021) a consultation on the Swansea Bay and West Wales Metro, considering improvements such as line speeds between Cardiff and West Wales and rail electrification.

In their manifestos:

  • Plaid Cymru promises to expand and electrify the rail network;
  • Welsh Labour states it is investing £750m to upgrade and electrify the South Wales Valleys lines to deliver better infrastructure, journey times and more trains; and
  • Welsh Conservatives do not mention rail electrification but promise to deliver rail infrastructure improvements, such as the West Wales Parkway, and improve rail links between North Wales and the North West of England.


South Wales Metro / Cardiff CrossRail light railway system

ICE Wales Cymru has called for “[i]ntegrated systems of heavy rail, light rail, metro and bus” and TfW is delivering the South Wales Metro, an “integrated public transport network that will make it easier for people travel across the Cardiff Capital Region, transforming rail and bus services as well as cycling and walking”.

Since 2013 there have also been plans to build a Cardiff CrossRail light railway system between Creigiau, to the east of Cardiff, to the new Cardiff Parkway station, to the west of Cardiff. However, questions remain over the affordability of this scheme.

In their manifestos:

  • Plaid Cymru promises add an extension to the Cardiff CrossRail light railway system with a Valleys CrossRail; and
  • Welsh Labour promises to deliver £800m of new rolling stock for Welsh railways, progress plans for a metro in North Wales and Swansea Bay, and explore opportunities for multi-modal extensions to Metro networks, such as the North West Corridor and across the South Wales valleys; and
  • Welsh Conservatives do not reference the Metro or Cardiff CrossRail.


Covid-19 has resulted in a challenging year for public transport across the UK, with a significant drop in passenger numbers and fall in income resulting in emergency measures and subsequently in Wales the nationalisation of the TfW rail network to bring financial stability and keep it running. It seems unlikely that the outcome of the election will reverse that decision.

Post Covid-19, it can be expected that the easing of travel restrictions, more flexible ticketing options, congestion, and a push towards more sustainable modes of transport will result in a resurgence in rail passenger numbers.

This is an exciting time for the South Wales region. With increased demand, political will and environmental, economic and social influences from other sources, we can expect pressure to build for the M4 relief road to be reconsidered in tandem with implementation of the South East Wales Transport Commission’s recommendations. However, without a clear majority, or a coalition aligned on these issues, will the main political parties in Wales need to compromise on their election promises?