The rain begins to fall at 'The Plug Hole', Ladybower Reservoir, Derbyshire, UK
The Ladybower Reservoir is a large Y-shaped reservoir, the lowest of three in the Upper Derwent Valley in Derbyshire, England. The River Ashop flows into the reservoir from the west; the River Derwent flows south, initially through Howden Reservoir, then Derwent Reservoir, and finally through Ladybower Reservoir. Its longest dimension is just over 3 miles, and at the time of construction it was the largest reservoir in Britain.
The water is used primarily for river control and to compensate for the water retained by the upper two dams, but water can also be fed into the drinking water system, however this is unusual as the water must be pumped to treatment works rather than using gravity flow like in the other two reservoirs, increasing costs. The drinking water is treated at Bamford water treatment works by Severn Trent Water. Treated water flows down the Derwent Valley Aqueduct to supply clean water to towns and cities in the East Midlands of England.
The building of the reservoir resulted in the 'drowning' of the villages of Derwent and Ashopton (including Derwent Woodlands church and Derwent Hall). Much of the structure of the village was still visible during a dry summer some fourteen years later, especially the church clock tower, however this has since been dismantled.
The area is now a popular tourist location, with the Fairholmes visitors' centre located at the northern tip of Ladybower.
The Ladybower Dam was built between 1935 and 1943, and took a further two years to fill (1945). The building of the dam wall was undertaken by the Scottish company of Richard Baillie and Sons. The two viaducts, Ashopton and Ladybower, needed to carry the trunk roads over the reservoir, were built by the London firm of Holloways, using a steel frame clad in concrete. Both firms encountered mounting problems when World War Two broke out in 1939 making labour and raw materials scarce. The opening ceremony for the reservoir was carried out on Tuesday September 25th 1945 by King George VI accompanied by Queen Elizabeth, later to become the Queen Mother.
During the 1990s the wall was raised and strengthened to reduce the risk of 'over-topping' in a major flood.
The dam's design is peculiar in having two totally enclosed bellmouth overflows (locally named the 'plugholes') at the side of the wall. The easterly overflow originally had a walkway around it but this was dismantled many years ago.
(Thanks to Kraigsta for the description).
Featured in "Momentum Magazine" (Canada) No. 38; (www.momentumplanet.com)