Plate taken from the 'Illustrated London News' (Vol 89/1 p 244). The huge masonry dam spans the river valley. Completed in 1889, it was the first large stone-built dam in Britain. Earlier dams had just been created by making earth embankments. Lake Vyrnwy was needed to provide a storage reservoir of safe water for the rapidly growing city of Liverpool. The factories too needed large quantities of water for their steam-driven machines.
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