Wild swim between the power stations

Half way down the Llennyrch gorge, is Rhaeadr Dhu, the Black Waterfall, a magical spot for a swim. We walked up the south west side of the valley – the best walk, but a tricky scramble down to the falls. It’s slightly easier access from the road on the opposite bank.

Despite the steel water pipes along the valley rim, it’s easy to forget Maentwrog hydro-electric power station at the foot of the valley, or even the two decommissioned Magnox reactors of Trawsfynydd a mile upstream, but we should thank them, and not just for the power they generated – flash floods made swimming risky until the dam was built.

In 1928 the original hydro-electric power station, provided 18 megawatts, enough for North Wales. Fifty years later it took the combined power of both nuclear reactors, 470MW, to supply the same area. Aren’t they impressive, nestled in the Welsh hills?

Trawsfynydd closed in 1991, and the only remaining Welsh nuclear power comes from Wylfa on Anglesey. But Maentwrog is still going. After upgrading it generates about 30 MW.

Jim Thornton