Reservoirs of Wales

There are a large number of reservoirs in Wales reflecting the need for the supply of water for both industry and for consumption, both within the country itself and in neighbouring England.

Wales has a relatively high rainfall and significant areas of mountainous topography which are sparsely populated which ensures that water is a plentiful natural resource.

Such engineering and economic views paid scant regard to the social, cultural and linguistic impacts that the constructions of large reservoirs in Wales would create.

Within Snowdonia, numerous existing natural lakes were co-opted to provide local water supplies during the late 19th and early 20th centuries.

Hafren Dyfrdwy (owned by Severn Trent) replaced these areas in 2018 and is aligned with the national border, serving 115,000 people in Wales.

[15] In 1964, residents of the small community of Aberbiga, composed of six farms, including Gronwen, Eblid, Ystradynod, Pen y Rhynau and Bwlch y Gle were evicted from their homes to create the Clywedog reservoir to supply the English midlands.

Birmingham Corporation had one hundred occupants moved out of their homes in the Elan Valley, Powys, to build the reservoirs.

Welsh Water is licensed to give 133 billion litres annually from Elan Valley reservoirs to Severn Trent customers.

[20] In 2022, Professor Roger Falconer said that England should "pay for the water", with the revenue being invested back into local communities in Wales.

He added, "We would supply directly under drought conditions to the south east of England and I would see this as the oil of Wales for the future in terms of revenue.

"[21] Former lecturer at Swansea University, John Ball has suggested that Welsh water is supplied to England is worth around £2bn annually.

Jane Dodds, leader of the Welsh Liberal Democrats, stated that she was "totally behind" the council's proposal plans, adding that they are a "step in the right direction".

[25] The GoWA 2006 was changed by the Wales Act 2017 which includes devolution of water and sewerage powers as recommended by the Silk Commission.

River regulation reservoirs are marginally cheaper to construct since there is no requirement for a take-off tower or associated large volume pipe-work or aqueducts piercing the dam wall.

Under this legislation, all reservoir owners in Wales and England were required to have them inspected by a suitably qualified civil engineer, if the capacity exceeded five million gallons (22,700 cubic metres).

The Reservoirs Act of 1975 placed further duties upon both owners and local authorities in respect of the safety of those with a capacity of more than 25,000 cubic metres.