[2] Work on the William Girling Reservoir was started in 1938, with John Mowlem & Co being the contractor,[3] but owing to technical problems, and the intervention of World War II, the reservoir was not finished until 1951.

They are comparatively shallow and provide open water habitat for wildfowl, gulls and waders.

[1] The reservoirs are major wintering grounds for wildfowl, including nationally important populations of shovelers and great crested grebes.

[1] Since the 1950s, the reservoirs have been providing a refuge for wildfowl while they are vulnerable during the late summer moult, and in some years, moulting flocks of great crested grebe have also used the reservoirs as a refuge.

The reservoirs have also been used by migratory birds as a stopover site in autumn and spring, and yellow wagtail regularly breed here.