River Usk
The River Usk (/ʌsk/; Welsh: Afon Wysg) rises on the northern slopes of the Black Mountain (y Mynydd Du), Wales, in the westernmost part of the Brecon Beacons National Park. Initially forming the boundary between Carmarthenshire and Powys, it flows north into Usk Reservoir, then east by Sennybridge to Brecon before turning southeast to flow by Talybont-on-Usk, Crickhowell and Abergavenny, after which it takes a more southerly course.
| River Usk | |
|---|---|
| Native name | Afon Wysg (Welsh) |
| Location | |
| Country | Wales |
| County | Powys, Carmarthenshire, Monmouthshire, Newport |
| Physical characteristics | |
| Source | |
| • location | Fan Brycheiniog, Carmarthenshire / Powys, Wales |
| • coordinates | 51°54′3″N 3°43′19″W |
| • elevation | 502 m (1,647 ft) |
| Mouth | Severn Estuary |
• location | Uskmouth, Newport, Wales |
• coordinates | 51°32′31″N 2°59′6″W |
• elevation | 0 m (0 ft) |
| Length | 125 km (78 mi) |
| Discharge | |
| • location | Chain Bridge (Usk) for 1957-2012 |
| • average | 27.919 m3/s (986.0 cu ft/s)for 1957-2012 |
| • minimum | 1.58 m3/s (56 cu ft/s)on 27 Aug 2003 |
| • maximum | 585.4 m3/s (20,670 cu ft/s)on 27 Dec 1979 |
| Basin features | |
| Tributaries | |
| • left | Afon Cilieni, Nant Brân, Afon Ysgir, Afon Honddu, Rhiangoll, Grwyne Fawr, River Gavenny, Olway Brook |
| • right | Afon Hydfer, Afon Crai, Afon Senni, Afon Tarell, Afon Cynrig, Nant Menasgin, Caerfanell, Afon Crawnon, Clydach, Berthin Brook, Sôr Brook, Afon Lwyd, Ebbw River |
Beyond the eponymous town of Usk, it passes the Roman legionary fortress of Caerleon to flow through the heart of the city of Newport and into the Severn Estuary at Uskmouth beyond Newport near the Newport Wetlands. The river is about 125 km (78 mi) long. According to the Encyclopaedia of Wales (which provides a figure of 137km), the river is the longest to flow wholly within Wales.
The Monmouthshire and Brecon Canal follows the Usk for most of the length of the canal.