River Swale

The River Swale in Yorkshire, England, is a major tributary of the River Ure, which becomes the River Ouse, that empties into the North Sea via the Humber Estuary. The river gives its name to Swaledale, the valley through which it flows. The river is said to be the fastest flowing in England and its levels have been known to rise 10 feet (3 m) in 20 minutes. Annual rainfall figures average 1800 mm p.a. in the headwaters and 1300 mm p.a. in the lower waters over a drop of 148 m in 32 km.