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Thursday 30 Oct 2025

Railway closure in South West Wales this weekend for major signalling upgrade

Region & Route:

Wales & Western: Wales & Borders

Buses will replace trains from Friday 31 October through the weekend between Carmarthen and Swansea as Network Rail switches the route over to new safer and more efficient digital technology

Rail passengers are advised that the railway will be closed between Carmarthen and Swansea on Friday 31 October, Saturday 1 and Sunday 2 November, while Network Rail engineers carry out major signalling upgrade works designed to modernise train control systems, improve train reliability and enhance safety across the region. 

The upgrade, part of phase two of Network Rail's Port Talbot West resignalling project, represents a significant step forward in the transition to digital signalling technology.

Over the past two and a half years, there have been 59 signalling failures between Carmarthen and Llanelli. The upgraded signalling and level crossing systems included in this programme are intended to address these issues. Through infrastructure improvements, safety updates, and more streamlined operations, Network Rail aims to reduce the frequency and duration of delays for both passengers and freight operators.

As part of the work this weekend:

• Four traditional signal boxes at Pembrey, Kidwelly, Ferryside and Carmarthen Junction will be retired, with train operations moving to remote digital control from Port Talbot.

• Level crossing enhancements will be delivered at four sites, including new barriers, enhanced obstacle detection systems and refreshed road markings to boost safety for road users and passengers.

• On-site attendants will be in place at Kidwelly, Bertwyn and Ferryside level crossings until December/January while commissioning of the new equipment takes place. Similar systems have already been successfully introduced at Duffryn and Llanelli station.

• The Pembrey relay room adjoining the former signal box will be demolished as part of the decommissioning works.

• Semaphore signals - the traditional arm-style indicators - will begin to be removed this weekend, with remaining structures to be dismantled and repurposed within the region over the coming months.

“These works mark a transformative moment for rail operations in South West Wales,” said Scott Beech, Project Manager.

“By centralising control and upgrading our signalling infrastructure, we’re not only improving reliability but also laying the groundwork for a safer and more responsive railway system that better serves our communities.

“We thank passengers in advance for their patience while this vital work is carried out.”

These works form part of Network Rail’s ongoing programme to strengthen rail infrastructure, improve safety standards, and support more reliable journeys for passengers across the Wales and Borders route.

Additional line closures between Swansea and Carmarthen are planned for Sundays 16 and 23 November to complete the final stages of the upgrade.

Buses will replace trains while this work is carried out and passengers are encouraged to check before they travel via National Rail Enquiries.

Network Rail apologises for any inconvenience caused and thanks passengers and local communities for their patience and cooperation during these essential improvements.