Ladybower Reservoir - Derbyshire Claimed

Ladybower Reservoir is a large Y-shaped reservoir, the lowest of three in the Upper Derwent Valley. 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.

The area is now a tourist attraction, with the Fairholmes Visitor' Centre located at the northern tip of Ladybower.

The dam differs from the Howden Reservoir and Derwent Reservoir in that it is a clay-cored earth embankment, and not a solid masonry dam.

Below the dam is a cut-off trench 180 feet (55 m) deep and 6 feet (1.8 m) wide filled with concrete, stretching 500 feet (150 m) into the hills each side, to stop water leaking round the dam. 

The dam's design is unusual in having two totally enclosed bellmouth overflows (locally named the "plugholes") at the side of the wall. These are stone and of 80 feet (24 m) diameter with outlets of 15 feet (4.6 m) diameter. Each discharges via its own valve house at the base of the dam. The overflows originally had walkways around them but they were dismantled many years ago.

The bell mouths are often completely out of the water and are only rarely