Thornton Reservoir is a small reservoir situated in the National Forest near the village of Thornton in Leicestershire. It has a surface area of 75 acres (300,000 m²) and a perimeter of 2.45 miles (3.94 km). It was originally built in 1854 when it had its own treatment works which were situated to the south of the current dam. It is now owned by Severn Trent and the water is treated a few miles away at Cropston Reservoir to which it runs via Rothley Brook. The reservoir is fed by two small streams which enter from the north via two weirs.