History

The South Wales Railway Company was formed in 1845, and the section of the line from Swansea to Carmarthen including the crossing at Lougher Estuary was completed in 1852. The engineer was Isambard Kingdom Brunel, and the track was at first constructed in broad gauge. LE Fletcher assisted in the design of the original viaduct. The present viaduct however has been rebuilt, and essentially dates from 1907, with strengthening in 1980. Firstly, in 1880, the original wooden spans were replaced with wrought iron girders supported on the original trestles; there were 18 spans of 40ft (12 metres), and a swing bridge on the E side.
In 1907 there was a major reconstruction. The swing span was dismantled, and the abutments rebuilt in stone. New trestles were driven, and a timber deck was installed. There were 17 spans in all. In 1980, the trestles were reconfigured by detaching the outer timbers and re-using them as sloping stays to improve lateral stability.

Exterior

A viaduct over 200m in length, consisting of four longitudinal girders of rivetted plate construction, carried on seventeen pile trestles. At each end is a substantial stone-faced embankment and abutment. An opening span at the west end has been replaced by a fixed span. The trestles each consist of eight timber piles driven in pairs, with walings to strap them together at low water level, plus cross-bracings, struts, and additional piles.

Reasons for Listing

Listed as a very rare surviving timber viaduct on a major railway.

External Links

• Cadwr Listing

External links are from the relevant listing authority and, where applicable, Wikidata. Wikidata IDs may be related buildings as well as this specific building. If you want to add or update a link, you will need to do so by editing the Wikidata entry.

Recommended Books

• 
  Sussex: West (Pevsner Architectural Guides: Buildings of England)
• 
  Gloucestershire 1: The Cotswolds: Cotswolds Pt. 1 (Pevsner Architectural Guides: Buildings of England)
• 
  Gloucestershire 2: The Vale and The Forest of Dean: Vale and Forest of Dean Pt. 2 (Pevsner Architectural Guides: Buildings of England)
• 
  Suffolk: West: The Buildings of England (Pevsner Architectural Guides) (Pevsner Architectural Guides: Buildings of England)
• 
  The Listed Buildings and Other Principal Structures at the Royal Gunpowder Mills Waltham Abbey
• 
  For the Record