In the 1870s Cheltenham was growing fast and its existing water supplies could not keep pace. The Corporation turned to the upper Chelt valley near Dowdeswell, where construction of a clay-lined earth dam began across the stream in 1883, with the reservoir completed and supplying water by 1886. The reservoir held 232 million gallons and was fed by springs filtering through the oolitic limestone of the surrounding hills — naturally pure water that needed minimal treatment. The Victorian engineers planted belts of beech and larch around the shoreline to stabilise the banks, and those trees have since matured into dense woodland that supports tawny owls, treecreepers, and three species of woodpecker. A second, smaller reservoir was added in 1892. Today the site is a Local Nature Reserve and a favourite stopping point for Cotswold Way walkers, who cross the dam wall on a path lined with wild garlic in spring. The old valve tower, a miniature castellated folly in dressed stone, still stands in the water — a reminder that this tranquil lake is entirely man-made.
“The Victorian engineers planted belts of beech and larch around the shoreline to stabilise the banks, and those trees have since matured into dense woodland that supports tawny owls, treecreepers, and three species of woodpecker.”
