DescriptionLower Clydach Aqueduct (Clydach) A3. One of three large single-arch aqueducts on the Swansea Canal (NPRN 34376) of which two survive (both in water). The Clydach Aqueduct is aligned obliquely north-east/south-west over the Lower Clydach River near its confluence with the River Tawe. The structure is of squared rubble with one 8.3m span. It is 2.2m high. The double overflows on the west side were rebuilt and in the 1950s two on the east were added during the rebuilding of the aqueduct's upper stages. Stumps of shallow flanking buttresses and a two-stone projecting string course, elliptical in section, have survived. In common with other aqueducts on the canal the water channel, which is 3.4m in width, were probably originally made watertight by an internal membrane of hydraulic lime mortar from Aberavon. The total width of the deck, 8.5m, gives an appearance as heavy as that of more conventional aqueducts sealed with puddled clay.
Aqueduct at SN 6892 0116
Stephen Hughes, 16.08.2006.