In 1879, George Deacon was instructed to prepare the parliamentary plans for the Vyrnwy Dam.
The valley was chosen because of its size, favourable geology and its source, the River Vyrnwy, having a large water catchment area.

Thomas Hawksley was appointed as engineer-in-chief and prepared the design for a stone dam.
 Dam construction with great blocks of Welsh slate started in 1881 and was completed in 1888.
Hawksley resigned in 1885 because of a conflict with George Deacon who was appointed as joint engineer.
The dam was the first large stone-built dam in the United Kingdom and cost £620,000 (equivalent to £70 million in 2016).
Earlier dams in Britain had been built using great earth embankments to hold back the water.
In 1889, shortly after completion, the lake was stocked with 400,000 Loch Leven trout.

Between 1881-92 the aqueducts carrying water to Liverpool were constructed.
In 1879, George Deacon was instructed to prepare the parliamentary plans for the Vyrnwy Dam. The valley was chosen because of its size, favourable geology and its source, the River Vyrnwy, having a large water catchment area.
Thomas Hawksley was appointed as engineer-in-chief and prepared the design for a stone dam.  Dam construction with great blocks of Welsh slate started in 1881 and was completed in 1888. Hawksley resigned in 1885 because of a conflict with George Deacon who was appointed as joint engineer. The dam was the first large stone-built dam in the United Kingdom and cost £620,000 (equivalent to £70 million in 2016). Earlier dams in Britain had been built using great earth embankments to hold back the water. In 1889, shortly after completion, the lake was stocked with 400,000 Loch Leven trout.
Between 1881-92 the aqueducts carrying water to Liverpool were constructed.
Lake Vyrnwy