In 2017, Transport for Wales commissioned the global consultancy company Mott MacDonald to undertake a full Feasibility Study into the re-instatement of the railway line between Aberystwyth and Carmarthen. The Study was funded by the Welsh Government (£300,000) to look into the ‘Case for Change’ in the improvement of strategic connections between Aberystwyth and Carmarthen that had been identified by the WelTAG Stage 1 ‘Outline Case Report, November 2016’, and to explore further the opportunities suggested by the previous Route Scoping Study.
The Feasibility Study broadly confirmed the technical feasibility of reinstating a modified route and train service, although a number of challenges were identified. These included crossing part of Cors Caron (an important SSSI, SAC and RAMSAR site); resolution of the flood-risk impacts and potential problems relating to bridge construction on the River Towy in the vicinity of Carmarthen; accommodation of the Gwili Railway Preservation Company; mitigation of extensive flood risks within Flood and Tan15 Development advice zones; property impacts; environment; and consents where the route passes through sites and features protected by statutory designations; and problems relating to ground conditions, residual structures and earthworks.
Subject to satisfactory resolution of these constraints, the Study concluded that the railway could be rebuilt and could provide a regular hourly service between Aberystwyth, Llanilar, Tregaron, Lampeter, Llanybydder, Pencader and Carmarthen, with an end to end journey time of around 85 minutes. With a potential opening year of 2024, initial demand assessments indicated that the re-instated railway could attract up to 370,000 trips in the first year of operation, rising to 425,000 and 489,000 in the assessment years 2027 and 2037 respectively.
A total cost build up of £775 million was envisaged for a single line formation; this included an optimism bias uplift of £276 million which is a general risk allowance reflecting HM Treasury/DfT guidance. The Study concluded that while there are no compelling engineering reasons why the railway should not be built, it suggested that low population levels along the line mean that, on purely economic grounds, the scheme does not present a positive case. Indeed a relatively low BCR (benefit to cost ratio) of 0.43 was assigned to the project. Hence progression of the scheme would need to be based on wider societal needs and strategic aims, both of which fell outside the remit of the Feasibility Study. It is the contention of Traws Link Cymru that wider societal needs and strategic aims do indeed support the case for reinstating the line, and we explain briefly why this is so in the Strategic Case section on this website, and in more detail in the document ‘A New Strategic Rail Corridor for West Wales’ (2020).