Location of the Anafon Hydro

The site of the Anafon Hydro lies in the Anafon valley in the Carneddau massif which rises immediately south of the village of Abergwyngregyn just inside the northern boundary of the Eryri (Snowdonia) National Park and 4 km west-south-west of Llanfairfechan.

The Afon Anafon originates in Llyn Anafon, a small, disused reservoir 5.1 km south-east of the village. The river descends rapidly for 3.3 km through open moorland and then through Coedydd Aber Forest to join the Afon Rhaeadr Fawr immediately upstream of Bontnewydd. The two tributaries form the Afon Aber which runs a further 2.3 km through the village and farmland to enter the eastern end of the Menai Strait at Traeth Lafan. The total descent of the river from Llyn Anafon is 558 m over 5.6 km.

The intake weir is situated 1.4 km downstream of the lake providing a catchment of 5.05 km2 and a head of 230m.