River Severn
The River Severn (Welsh: Afon Hafren, pronounced [ˈavɔn ˈhavrɛn]), at 220 miles (354 km) long, is the longest river in Great Britain. It is also the river with the most voluminous flow of water by far in all of England and Wales, with an average flow rate of 107 m3/s (3,800 cu ft/s) at Apperley, Gloucestershire. It rises in the Cambrian Mountains in mid Wales, at an altitude of 2,001 feet (610 m), on the Plynlimon massif, which lies close to the Ceredigion/Powys border near Llanidloes. The river then flows through Shropshire, Worcestershire and Gloucestershire. The county towns of Shrewsbury, Gloucester and Worcester lie on its course.
| River Severn | |
|---|---|
The river seen from Shrewsbury Castle | |
Tributaries (light blue) and major settlements on and near the Severn (bold blue) | |
| Location | |
| Country | England and Wales |
| Region | Mid Wales, West Midlands, South West |
| Counties | Powys, Shropshire, Worcestershire, Gloucestershire |
| Cities | Shrewsbury, Worcester, Gloucester, Bristol |
| Physical characteristics | |
| Source | |
| • location | Plynlimon, Powys, Wales |
| • coordinates | 52.493464°N 3.734597°W |
| • elevation | 610 m (2,000 ft) |
| Mouth | Severn Estuary |
• location | Bristol Channel, United Kingdom |
• elevation | 0 m (0 ft) |
| Length | 354 km (220 mi) |
| Basin size | 11,420 km2 (4,410 sq mi) |
| Discharge | |
| • location | Bewdley, Worcs. SO 7815 7622 |
| • average | 61.17 m3/s (2,160 cu ft/s) |
| • maximum | 533.48 m3/s (18,840 cu ft/s)max recorded on 1947-03-21 |
| Discharge | |
| • location | Apperley, Glos. |
| • average | 107 m3/s (3,800 cu ft/s) |
| Discharge | |
| • location | Montford, Shrops. |
| • average | 43.46 m3/s (1,535 cu ft/s) |
| Basin features | |
| Tributaries | |
| • left | Vyrnwy, Tern, Stour, Warwickshire Avon, Bristol Avon |
| • right | Teme, Leadon, Wye |
The Severn's major tributaries are the Vyrnwy, the Tern, the Teme, the Warwickshire Avon, and the Worcestershire Stour.
By convention, the River Severn is usually considered to end, and the Severn Estuary to begin, after the Second Severn Crossing, between Severn Beach in South Gloucestershire and Sudbrook, Monmouthshire. The total area of the Estuary's drainage basin is 4,409 square miles (11,419 km2). That figure excludes the area of the River Wye and the Bristol Avon, both of which flow into the Severn Estuary. The Estuary discharges into the Bristol Channel, which opens into the Celtic Sea and from there into the Atlantic Ocean.