Part of the Elan Aqueduct (nprn 95469), itself part of the Elan Valley Water Scheme (nprn 96459), the Wye Syphon carries the pipeline over the River Wye. It consists of the syphon inlet and overflow chamber (nprn 309606), the Wye aqueduct (nprn 309613) and adjacent washout chamber (nprn 309614) and the syphon outlet (nprn 309615) and covers a distance of some 0.77km.

B.A.Malaws, 08 December 2003.