An important element in managing the commons for stock was providing a reliable supply of water. Where the valleys have exposed impervious layers of clay beneath the sandstone or where bands of tabular sandstone outcrop, small springs or seepage occur. These may have been used by stock for water. A recently constructed pond lies on Holmbury Hill itself, at the top of a main hollow way from the Radnor Road. It was constructed in a possibly small quarry or depression as it is shown on the OS 6” 1st Edition.
Today a number of small ponds have been made by constructing dams across the ditches in the valley bottoms. Most are for controlling run-off during heavy rain and preventing flooding in the villages. They are also an important source of water at times of fire.