Coedty Reservoir

Coedty Reservoir lies high in Snowdonia, fed by the Afon Porth-llwyd from Llyn Eigiau. It sits nine hundred feet above sea level and covers twelve acres, holding brown trout in its waters. The reservoir’s dam was first built in 1924 to supply hydro-electric power to the aluminium works at Dolgarrog. In 1925 the Eigiau dam failed and the flood burst Coedty’s dam as well. Sixteen lives were lost in Dolgarrog when the water rushed downstream. The dam was rebuilt the next year and altered again in 1956 to restore safe operation. Visitors walk the trackbed of the old Eigiau Tramway along the eastern shore. Nearby the Cowlyd Tramway branches off toward Llyn Cowlyd. A metal pipe carries water three kilometres down to the power station at Dolgarrog. When levels rise, water spills into a dramatic gorge used for gorge walking, though sudden releases make this activity risky.