Ladybower Reservoir, Derbyshire 

Ladybower Reservoir is a large Y-shaped, artificial 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. The reservoir is owned by Severn Trent.