Cwm Clydach Dam (partly in Dyffryn Clydach community)

Location

Spanning Cwm Clydach approximately 950m N of Neath Abbey railway viaduct and some 120m NE of Glynfelin Farm.

History

Dam, built 1840 to renew earlier structure. It was used to regulate the flow of water to Neath Abbey Ironworks some 1 km downstream. Water power was widely used in the works even after the advent of steam power. In 1840 the Neath Abbey Iron Company had two rolling mills and a boring mill powered by waterwheels. The Neath Abbey Ironworks were developed by two Quaker families, the Foxes of Falmouth from 1792 and Joseph Tregelles Price from 1817. Under Price the works became famous for high-quality engineering products including locomotives, stationary engines and steamships. The works closed in 1886.

Exterior

Dam, high wall of Pennant sandstone with battered lower face. W end has buttresses between twin outlets from vertical cast-iron tubes, one with cast-iron paddle gearing on N side. Four overflow outlets above, all with cast-iron stop-plank supports. Dam carries minor roadway with, from E, rubble stone walls, C20 railings, C20 rubble stone walls and then concreted walls on W end. The reservoir is heavily silted almost to road level.

Reason for designation

Included as a well-built stone dam of the earlier C19 and of special historical interest as part of the former Neath Abbey Ironworks. Scheduled Ancient Monument GM395.