Ty Mawr Reservoir

The reservoir opened in 1908, and is operated today by Hafren Dyfrdwy on behalf of Severn Trent. It is 8.6 ha in area, of moderate alkalinity, humic and a shallow reservoir of a mean depth of 10 m. It is part of a system of several small reservoirs including the Cae Llwyd Reservoir and Pen-y-Cae Reservoirs. The water of the lake is sourced from the drainage basin of the Pentre-bychan Brook and the Cae Llwyd Reservoir located at a higher elevation to the west of the reservoir. The catchment area of the lake is 19 ha. It holds the greatest continuous embankment length (600 m) of any of the reservoirs operated by Severn Trent, and the embankment is made of a clay core. It can hold a capacity…