The River Severn (Welsh: Afon Hafren, pronounced [ˈavɔn ˈhavrɛn]) is the longest river in Great Britain, with a length of 220 miles (354 km). 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 610 m (2,000 ft), 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, Worcester and Gloucester lie on its course.
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 Prince of Wales Bridge, 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.
Etymology
Celtic Root
An etymology has been proposed, which signifies that 'Severn' is an anglicised version of an ancient Celtic phrase signifying 'a gap (in the coastline)', referring to the estuary.
Romano-British name
The name Severn is thought to derive from a British word sabrinā, possibly from an older form *samarosina, meaning "land of summertime fallow".
During the Roman occupation the Severn was known by the Romano-British Latin name Sabrina.
Welsh name
The Welsh form of the name is Afon Hafren (pronounced [ˈavɔn ˈhavrɛn]) first recorded in the 12th-century Historia Regum Britanniae. The Old Welsh form of the name Habren was recorded c.800.
Documented history of the Welsh name:
Habren c.800.
Hauren c.1170.
hahafrenn, 12th century.
Dyffrin hawren, mid 13th century.
The toponym for Habren might be:
High prow of a ship.
High prow of a wave.
English name
The English form of the name ("Severn") is derived from Old English Sæfern. However the name is also influenced by English dialect seave ("sedge, rush") hence the origin of the name Seaverne recorded in the 16th–17th century.
Common club-rush (Schoenoplectus lacustris) prefers to grow in shallow water such as that found in ponds, streams and river margins. The Hwicce people used the club-rush growing along the banks of the River Severn to make wicker baskets.
Name history
The name history shows evidence of Scandinavian influence:
Viking age
In the Summer of 893 a coalition of all of the Danish armies in England made a determined attempt to annex western Mercia to Danish Mercia. The Anglo-Saxon Chronicle (ASC) recorded an account of the Battle of Buttington, and included this description of the route taken by the Danes:
"... Foron þa up be Temese oþþæt hie gedydon æt Sæferne, þa up be Sæferne.
Seafarer
The name Sæfern might be related to:
The Sea.
Middle English faren – "travel".
Old Norse sær – "the sea, ocean".
Old Norse fara – "to fare, to travel".
The Old Norse personal name Sæfari – "Seafarer".
The Old Norse name Sæfari ("Seafarer") lives on as the name of the Dalvík – Grímsey ferry in Iceland.
Geography and geology
The River Severn's current form is the result of a multi-million year history and complex underlying geology, shaped in part by glaciation during the last ice age in the Pleistocene epoch of the Quaternary period. Within Wales, the river runs through a landscape formed in Ordovician and Silurian rocks. As it enters the Shropshire Plain, these lower Palaeozoic rocks are replaced by Permian and Triassic age strata though largely unseen beneath a thick cover of Quaternary deposits. Certain stretches also run across Carboniferous strata as at Shrewsbury and for much of the distance between Ironbridge and Bewdley. Permo-Triassic bedrock then continues until the Severn moves intermittently onto the Jurassic outcrop from Tewkesbury southwards. Only in the SSW-NNE aligned valley either side of Welshpool is there any obvious relationship to geological structure where the valley follows the lines of the Severn Valley Fault Belt. For much of the rest of its course it runs directly across geological structures.
It was first proposed in the 1900s that the former northerly course of the upper Severn was disrupted during the ice age by the blocking of its access to the Irish Sea through Cheshire, causing a large lake to develop across much of Shropshire. It was supposed that this lake, named as Lake Lapworth, overtopped its southern margin and rapidly cut down to form the Ironbridge Gorge providing the Severn with a southerly exit to the sea as remains the case today. An alternative theory which has gained favour in recent years does away with Lake Lapworth, suggesting that the upper Severn flowed beneath the icesheet in a bedrock hollow known as the Severn Trench eastwards from Melverley to the Ironbridge Gorge. It is possible that the trench and gorge were cut over successive ice ages.
Tributary rivers
Over its length, there are a large number of tributaries, but the three largest feeding the non-tidal river are the Vyrnwy, the Teme and the Warwickshire Avon. The Wye, the Bristol Avon and the Usk all flow into the estuarine section of the Severn. The main tributaries are described in sequence below.
The first tributary of significance is the Afon Dulas, joining from the south immediately upstream of Llanidloes, with the Afon Clywedog joining in the town. The Afon Cerist, bolstered by the Afon Trannon, and the Afon Carno join as left bank tributaries immediately upstream of Caersws. Mochdre Brook enters on the western edge of Newtown, followed by the Bechan Brook just northeast of the town. The Mule enters at Abermule, and the River Rhiw east of Berriew, followed shortly by the Camlad which rises above Churchstoke and by the Luggy Brook. The left bank Sylfaen Brook enters at Welshpool, and the Bele Brook via the New Cut east of Arddlin.
The River Vyrnwy, which begins at Lake Vyrnwy, flows eastwards through Powys, gathering the waters of the Banwy, Cain and Tanat, before forming part of the border between England and Wales, and joining the Severn near Melverley, Shropshire. The River Perry joins on the left bank above Shrewsbury, while both the Rad Brook and the Rea Brook, which flows northeast from its source at Marton Pool near the Welsh border, join the Severn within the town. The left bank tributary, the River Tern, after flowing south from Market Drayton and being joined by the River Meese and the River Roden, meets the Severn at Attingham Park.
The River Worfe joins the Severn's left bank just above Bridgnorth, before the Mor, Borle and Dowles brooks join on the opposite bank over the next few miles, the last-named draining Wyre Forest. The River Stour rises in the north of Worcestershire in the Clent Hills, near St Kenelm's Church at Romsley. It flows north into the adjacent West Midlands at Halesowen. It then flows westwards through Cradley Heath and Stourbridge, where it leaves the Black Country. It is joined by the Smestow Brook at Prestwood before it winds around southwards to Kinver, and then flows back into Worcestershire. It then passes through Wolverley, Kidderminster and Wilden to its confluence with the Severn at Stourport-on-Severn. The Dick Brook, Shrawley Brook and Grimley Brook enter on the right bank before the River Salwarpe, which runs through Droitwich enters on the opposite (east) bank.
The River Teme flows eastwards from its source in Mid Wales, straddling the border between Shropshire and Herefordshire; it is joined by the River Onny, River Corve and River Rea before it finally joins the Severn on the southern edge of Worcester. Bushley Brook joins just upstream of the confluence of the Warwickshire Avon with the Severn at Tewkesbury. One of several Avons, this one flows west through Rugby, Warwick and Stratford-upon-Avon. It is then joined by its tributary the River Arrow, before joining the Severn. The rivers Swilgate and Chelt also join the Severn's left bank, as do the Hatherley and Horsbere brooks, before it reaches Gloucester. The River Leadon enters the tidal West Channel of the Severn at Over, immediately west of Gloucester. The River Frome is the second significant tributary to enter the tidal stretch of the Severn, doing so at Framilode. Bideford Brook drains the easternmost part of the Forest of Dean, entering the Severn estuary east of Blakeney. On the opposite (southeast) bank the flow of the River Cam is usurped by the Gloucester and Sharpness Canal before reaching the estuary. The Lyd enters the west bank of the estuary at Lydney Harbour, opposite the place where Berkeley Pill carries the waters of the Little Avon River into it. The final tributary before the Severn Bridge is the collection of streams which enter via Oldbury Pill.
The River Wye, from its source in Plynlimon in Wales (2 miles (3 km) from the source of the Severn), flows generally south east through the Welsh towns of Rhayader and Builth Wells. It enters Herefordshire, flows through Hereford, and is shortly afterwards joined by the River Lugg, before flowing through Ross-on-Wye and Monmouth, and then southwards where it forms part of the border between England (Forest of Dean) and Wales. The Wye flows into the Severn estuary south of the town of Chepstow.
The Mounton Brook and Nedern Brooks enter on the Monmouthshire side between the two motorway crossings. The Port of Bristol is on the Severn Estuary, where another River Avon flows into it through the Avon Gorge. The River Usk and the Ebbw River flow into the Severn Estuary at Uskmouth just south of Newport.
Settlements
The river's course within Wales lies wholly within the county of Powys. The first town it encounters downstream of its source is Llanidloes where it is joined by the Dulas and the Clywedog. It flows past the villages of Llandinam and Caersws before reaching Newtown. It then runs by Abermule and Cilcewydd before flowing beside Welshpool, the last town on its course in Wales.
Entering Shropshire and England, a few villages such as Shrawardine sit back from the river as it meanders eastwards towards the county town of Shrewsbury. More villages, notably Atcham, Wroxeter and Cressage sit beside the river as it turns southeast and heads for the gorge at Ironbridge before turning south for Bridgnorth. The Shropshire villages of Quatford and Hampton Loade and the Worcestershire village of Upper Arley follow, before the Severn runs through Bewdley and Stourport-on-Severn in quick succession. The river then passes the villages of Astley Burf and Holt Fleet before entry into the city of Worcester. Several villages sit back from the river before it runs by Upton upon Severn and then enters Gloucestershire as it joins with the Warwickshire Avon outside of Tewkesbury. A few more villages intervene, notable amongst which is Maisemore before the river enters the city of Gloucester from which point it is tidal.
Several more villages sit beside the tidal stretch. Amongst these are Elmore, Epney and Framilode on the east bank and Minsterworth, Broadoak and Newnham on Severn on the west bank.
Transport
Bridges
The Severn is bridged at many places, and many of these bridges are notable in their own right. The Iron Bridge at Ironbridge was the world's first iron arch bridge. Several other bridges crossing the river were designed and built by the engineer Thomas Telford.
The two major road bridges of the Severn crossing link south eastern Wales with the southern counties of England.
Severn Bridge – opened in 1966 carrying what is now the M48
Prince of Wales Bridge – opened in 1996 carrying the M4 motorway, known as the Second Severn Crossing until 2018
Prior to the construction of the first bridge in 1966, the channel was crossed by the Aust Ferry.
Other notable bridges include:
Buttington Bridge – built in 1872
Montford Bridge – Thomas Telford's first ever bridge design, built between 1790 and 1792