Timber Aqueduct over Former Taff Bargoed Railway

Cadw's description

Location

Located on the deep railway cutting west of Cwm Bargoed coal preparation plant.

History

A timber aqueduct for the complex system of water supply to Dowlais Ironworks. The watercourse system was developed on Cwmbargoed Mountain from c1818, and the Sarn Howell Watercourse at around this point was in operation by 1839. At this time, the Dowlais Ironworks was the largest in the world, and made use of large amounts of water for water balance winding gears at its mines, water power at the ironworks, steam engines, and cooling. Watercourse and reservoirs evolved into a uniquely large and densely developed industrial water control system which was described by John A. Owen in 1977 as ‘truly the work of genius.’ This was in use until the 1960s. The aqueduct was built c1876 to cross the Taff Bargoed branch of the joint Rhymney and Great Western Railway. Such timber structures were common on railways in the nineteenth century, but are now rare. The remains of a similar but collapsed structure lie just to the west.

Exterior

The aqueduct is constructed of traditional techniques of joists and planks. It has two spans, from masonry and brick abutments across two timber trestle piers. The plank sides of the aqueduct are held in place by timber cross members above and below them, tied vertically be wrought iron rods. The whole structure is some 32m in length.

Reason for designation

Listed as a rare surviving timber aqueduct and as a significant feature of the important water power system supplying Dowlais Ironworks.