Alwen Reservoir

The Alwen Reservoir lies in the hills of Conwy County Borough in North Wales. The reservoir stretches for five kilometres through a long valley near Pentre-Llyn-Cymmer. It is held back by the 27-metre-high Alwen Dam on the Afon Alwen. The dam was built between 1909 and 1921 by engineers Alexander Binnie, Son and Deacon. The reservoir was designed to supply drinking water to Birkenhead and parts of Liverpool.

The reservoir remains an important water source today. It is the only reservoir in the Dee system that sends water directly through a piped supply. Welsh Water runs an education scheme for children linked to the National Curriculum. The nearby Outdoor Education Centre at Pentre-Llyn-Cymmer hosts school trips with guided tours of the water treatment works.

Visitors find a quiet upland landscape with forests on either side. Public footpaths and forest roads wind around the reservoir, suitable for walking, horse riding and mountain biking. The reservoir has no through routes for vehicles, so the trails are peaceful and undisturbed. The upgraded paths from 2005 and 2006 make the area easier to explore. Fishing is allowed with a permit from the nearby Llyn Brenig visitors centre.