A drainage basin is an area of land in which all flowing surface water converges to a single point, such as a river mouth , or flows into another body of water , such as a lake or ocean . A basin is separated from adjacent basins by a perimeter, the drainage divide , made up of a succession of elevated features, such as ridges and hills . A basin may consist of smaller basins that merge at river confluences , forming a hierarchical pattern .
72-691: The Tar Tunnel is an abandoned tunnel located on the north bank of the River Severn in the Ironbridge Gorge at Coalport , England . It is one of ten Ironbridge Gorge Museums attractions administered by the Ironbridge Gorge Museum Trust . Miners struck a gushing spring of natural bitumen , a black treacle -like substance, when digging a canal tunnel for the Coalport Canal in 1787, or else digging
144-642: A broad beam canal, joins the Severn at Hawford , near to the River Salwarpe , and connects to the Droitwich Canal (narrow beam) in the name town, which then forms a link to the Worcester and Birmingham Canal. The two Droitwich canals re-opened in 2010 after major restoration. The Gloucester and Sharpness Canal connects the Severn at Gloucester to the Severn at Sharpness , avoiding a stretch of
216-437: A common task in environmental engineering and science. In a closed drainage basin, or endorheic basin , rather than flowing to the ocean, water converges toward the interior of the basin, known as a sink , which may be a permanent lake, a dry lake , or a point where surface water is lost underground . Drainage basins are similar but not identical to hydrologic units , which are drainage areas delineated so as to nest into
288-454: A drainage basin, and there are different ways to interpret that data. In the unlikely event that the gauges are many and evenly distributed over an area of uniform precipitation, using the arithmetic mean method will give good results. In the Thiessen polygon method, the drainage basin is divided into polygons with the rain gauge in the middle of each polygon assumed to be representative for
360-540: A drainage boundary is referred to as watershed delineation . Finding the area and extent of a drainage basin is an important step in many areas of science and engineering. Most of the water that discharges from the basin outlet originated as precipitation falling on the basin. A portion of the water that enters the groundwater system beneath the drainage basin may flow towards the outlet of another drainage basin because groundwater flow directions do not always match those of their overlying drainage network. Measurement of
432-469: A level in search of coal. The plan, proposed by William Reynolds , was to connect the canal alongside the River Severn to the lower galleries of the mines below the Blists Hill area. After digging around 3,000 feet (910 m) into the hill the canal project was abandoned in favour of bitumen extraction. The tunnel was a great curiosity in the eighteenth century and bitumen still oozes gently from
504-602: A multi-level hierarchical drainage system . Hydrologic units are defined to allow multiple inlets, outlets, or sinks. In a strict sense, all drainage basins are hydrologic units but not all hydrologic units are drainage basins. About 48.71% of the world's land drains to the Atlantic Ocean . In North America , surface water drains to the Atlantic via the Saint Lawrence River and Great Lakes basins,
576-520: Is a stub . You can help Misplaced Pages by expanding it . 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 m /s (3,800 cu ft/s) at Apperley , Gloucestershire. It rises in
648-487: Is referred to as " watershed management ". In Brazil , the National Policy of Water Resources, regulated by Act n° 9.433 of 1997, establishes the drainage basin as the territorial division of Brazilian water management. When a river basin crosses at least one political border, either a border within a nation or an international boundary, it is identified as a transboundary river . Management of such basins becomes
720-614: Is the Dead Sea . Drainage basins have been historically important for determining territorial boundaries, particularly in regions where trade by water has been important. For example, the English crown gave the Hudson's Bay Company a monopoly on the fur trade in the entire Hudson Bay basin, an area called Rupert's Land . Bioregional political organization today includes agreements of states (e.g., international treaties and, within
792-648: 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 . Milton 's 1634 masque Comus makes Sabrina a nymph who had drowned in the river. In Shrewsbury , there is now a statue of Sabrina in the Dingle Gardens at
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#1732783030242864-408: 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. 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
936-713: The African Great Lakes , the interiors of Australia and the Arabian Peninsula , and parts in Mexico and the Andes . Some of these, such as the Great Basin, are not single drainage basins but collections of separate, adjacent closed basins. In endorheic bodies of water where evaporation is the primary means of water loss, the water is typically more saline than the oceans. An extreme example of this
1008-594: The Arkendale H and Wastdale H died in the accident. There have been frequent floods in Shrewsbury , Bewdley and elsewhere. More recently the river flooded during the 2007 United Kingdom floods and the 2019–20 United Kingdom floods . There is a public right of navigation between Pool Quay , near Welshpool , and Stourport. However this stretch of the river has little traffic, other than small boats, canoes and some tour boats in Shrewsbury. Below Stourport, where
1080-633: 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 , Worcester and Gloucester lie on its course. The Severn's major tributaries are the Vyrnwy ,
1152-636: 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
1224-607: The Eastern Seaboard of the United States, the Canadian Maritimes , and most of Newfoundland and Labrador . Nearly all of South America east of the Andes also drains to the Atlantic, as does most of Western and Central Europe and the greatest portion of western Sub-Saharan Africa , as well as Western Sahara and part of Morocco . The two major mediterranean seas of the world also flow to
1296-791: The Gloucester and Sharpness Canal provides a navigable channel south. Between the docks and Lower Parting Llanthony Weir marks the Normal Tidal Limit (NTL) of the East Channel of the river. In the tidal section of the river below Gloucester, the Gloucester Harbour Trustees are the competent harbour authority. The Trustees maintain navigation lights at various points along the river (including on Chapel Rock and Lyde Rock, and leading lights at Slime Road, Sheperdine and Berkeley Pill). There are locks on
1368-481: 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
1440-735: The Mississippi (3.22 million km ), and the Río de la Plata (3.17 million km ). The three rivers that drain the most water, from most to least, are the Amazon, Ganges , and Congo rivers. Endorheic basin are inland basins that do not drain to an ocean. Endorheic basins cover around 18% of the Earth's land. Some endorheic basins drain to an Endorheic lake or Inland sea . Many of these lakes are ephemeral or vary dramatically in size depending on climate and inflow. If water evaporates or infiltrates into
1512-809: The Nile River ), Southern , Central, and Eastern Europe , Turkey , and the coastal areas of Israel , Lebanon , and Syria . The Arctic Ocean drains most of Western Canada and Northern Canada east of the Continental Divide , northern Alaska and parts of North Dakota , South Dakota , Minnesota , and Montana in the United States, the north shore of the Scandinavian peninsula in Europe, central and northern Russia, and parts of Kazakhstan and Mongolia in Asia , which totals to about 17% of
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#17327830302421584-534: The Quarry , as well as a metal sculpture erected in 2013. There is a different deity associated with the Severn Estuary: Nodens , represented as mounted on a seahorse , riding on the crest of the Severn bore . 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
1656-647: 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
1728-771: The Second Severn Crossing road bridge, and carries the South Wales Main Line section of the Great Western Main Line under the channel. The original line built before the Severn Tunnel was the South Wales Railway from Gloucester , that followed the estuary alongside present day stations of Lydney , Chepstow , Caldicot and Severn Tunnel Junction to Newport . Cars could also be transported through
1800-897: 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 km ). That figure excludes
1872-728: 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
1944-789: The Andes. The Indian Ocean 's drainage basin also comprises about 13% of Earth's land. It drains the eastern coast of Africa, the coasts of the Red Sea and the Persian Gulf , the Indian subcontinent , Burma, and most parts of Australia . The five largest river basins (by area), from largest to smallest, are those of the Amazon (7 million km ), the Congo (4 million km ), the Nile (3.4 million km ),
2016-726: The Atlantic. The Caribbean Sea and Gulf of Mexico basin includes most of the U.S. interior between the Appalachian and Rocky Mountains , a small part of the Canadian provinces of Alberta and Saskatchewan , eastern Central America , the islands of the Caribbean and the Gulf, and a small part of northern South America. The Mediterranean Sea basin, with the Black Sea , includes much of North Africa , east-central Africa (through
2088-515: 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
2160-550: The SSW-NNE aligned valley either side of Welshpool is there any obvious relationship to geological structure; the valley follows the lines of the Severn Valley Faults. 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 course of the ice age by the blocking of its access to
2232-607: The Severn Estuary from the mid 19th century to the late 1970s by P & A Campbell of Bristol . The vessels, Cardiff Queen , Bristol Queen , Glen Usk , Glen Gower and Britannia all operated on this route in the 1950s and 1960s. Since 1986 Waverley Excursions has operated occasional sailings to Sharpness and Lydney by the MV Balmoral . A number of ferries were also operated on the tidal river, for example at New Passage , Purton and Arlingham . The last ferry
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2304-464: The Severn Tunnel. In the 1950s three trains a day made round trips between Severn Tunnel Junction and Pilning . The vehicles were loaded onto open flat bed carriages and pulled by a small pannier tank locomotive , although sometimes they were joined to a scheduled passenger train. The prudent owner paid to cover the vehicle with a sheet, as sparks often flew when the steam locomotive tackled
2376-538: 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
2448-469: 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
2520-569: 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
2592-417: The US, interstate compacts ) or other political entities in a particular drainage basin to manage the body or bodies of water into which it drains. Examples of such interstate compacts are the Great Lakes Commission and the Tahoe Regional Planning Agency . In hydrology , the drainage basin is a logical unit of focus for studying the movement of water within the hydrological cycle . The process of finding
2664-421: 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. An etymology has been proposed, which signifies that 'Severn' is an anglicized version of a ancient Celtic phrase signifying 'a gap (in the coastline)', referring to the estuary. The name Severn
2736-406: The basin, it can form tributaries that change the structure of the land. There are three different main types, which are affected by the rocks and ground underneath. Rock that is quick to erode forms dendritic patterns, and these are seen most often. The two other types of patterns that form are trellis patterns and rectangular patterns. Rain gauge data is used to measure total precipitation over
2808-489: The boats The Pride of the Midlands and The Earl Grosvenor . Drainage basin Other terms for a drainage basin are catchment area , catchment basin , drainage area , river basin , water basin , and impluvium . In North America, they are commonly called a watershed , though in other English-speaking places, "watershed" is used only in its original sense, that of the drainage divide line. A drainage basin's boundaries are determined by watershed delineation ,
2880-451: The brick walls today. Bitumen's chief commercial use at the time was to treat and weatherproof ropes and caulk wooden ships , but small amounts were processed and bottled as 'Betton's British Oil', a panacea remedy for rheumatism and scurvy . After the canal project was abandoned the Hay Inclined Plane was built instead, its base being alongside the canal basin. In the past visitors were provided with hard hats and were able to enter
2952-409: The club-rush growing along the banks of the River Severn to make wicker baskets. The name history shows evidence of Scandinavian influence: 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
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3024-429: 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
3096-430: The discharge of water from a basin may be made by a stream gauge located at the basin's outlet. Depending on the conditions of the drainage basin, as rainfall occurs some of it seeps directly into the ground. This water will either remain underground, slowly making its way downhill and eventually reaching the basin, or it will permeate deeper into the soil and consolidate into groundwater aquifers. As water flows through
3168-441: The drainage area is dependent on the soil type. Certain soil types such as sandy soils are very free-draining, and rainfall on sandy soil is likely to be absorbed by the ground. However, soils containing clay can be almost impermeable and therefore rainfall on clay soils will run off and contribute to flood volumes. After prolonged rainfall even free-draining soils can become saturated , meaning that any further rainfall will reach
3240-642: The drainage basin to the mouth, and may accumulate there, disturbing the natural mineral balance. This can cause eutrophication where plant growth is accelerated by the additional material. Because drainage basins are coherent entities in a hydrological sense, it has become common to manage water resources on the basis of individual basins. In the U.S. state of Minnesota , governmental entities that perform this function are called " watershed districts ". In New Zealand, they are called catchment boards. Comparable community groups based in Ontario, Canada, are called conservation authorities . In North America, this function
3312-407: The first 300 feet (91 m) of the brick-lined tunnel as far as an iron gate. Electric lighting is provided. Due to a build up of gas in the tunnel, it is unsafe to enter but visitors can still get a view along part of its length from the entrance. 52°37′12″N 2°27′9″W / 52.62000°N 2.45250°W / 52.62000; -2.45250 This Shropshire location article
3384-435: The ground and along rivers it can pick up nutrients , sediment , and pollutants . With the water, they are transported towards the outlet of the basin, and can affect the ecological processes along the way as well as in the receiving water body . Modern use of artificial fertilizers , containing nitrogen (as nitrates ), phosphorus , and potassium , has affected the mouths of drainage basins. The minerals are carried by
3456-422: The ground at its terminus, the area can go by several names, such playa, salt flat, dry lake , or alkali sink . The largest endorheic basins are in Central Asia , including the Caspian Sea , the Aral Sea , and numerous smaller lakes. Other endorheic regions include the Great Basin in the United States, much of the Sahara Desert , the drainage basin of the Okavango River ( Kalahari Basin ), highlands near
3528-421: The lower Severn to enable seagoing boats to reach as far as Stourport. The most northerly lock is at Lincomb, about 1 mile (1.6 km) downstream from Stourport. The Staffordshire and Worcestershire Canal , the Worcester and Birmingham Canal , (both narrow beam) and the Herefordshire and Gloucestershire Canal join the Severn at Stourport, Worcester and Gloucester respectively. The Droitwich Barge Canal ,
3600-533: The name Habren was recorded c.800. Documented history of the Welsh name: The toponym for Habren might be: 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
3672-400: The name of the Dalvík – Grímsey ferry in Iceland . The River Severn's current form is the result of a multi-million year history and complex underlying geology but is in part the result of 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
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#17327830302423744-485: 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
3816-418: The rainfall on the area of land included in its polygon. These polygons are made by drawing lines between gauges, then making perpendicular bisectors of those lines form the polygons. The isohyetal method involves contours of equal precipitation are drawn over the gauges on a map. Calculating the area between these curves and adding up the volume of water is time-consuming. Isochrone maps can be used to show
3888-572: The responsibility of the countries sharing it. Nile Basin Initiative , OMVS for Senegal River , Mekong River Commission are a few examples of arrangements involving management of shared river basins. Management of shared drainage basins is also seen as a way to build lasting peaceful relationships among countries. The catchment is the most significant factor determining the amount or likelihood of flooding . Catchment factors are: topography , shape, size, soil type, and land use (paved or roofed areas). Catchment topography and shape determine
3960-478: 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
4032-439: The river is more navigable for larger craft, users must obtain permits from the Canal & River Trust , who are the navigation authority . During spring freshet the river can be closed to navigation. At Upper Parting above Gloucester, the river divides into two, and flows either side of Alney Island to Lower Parting. The West Channel is no longer navigable. The East Channel is navigable as far as Gloucester Docks, from where
4104-461: The river rather than being absorbed by the ground. If the surface is impermeable the precipitation will create surface run-off which will lead to higher risk of flooding; if the ground is permeable, the precipitation will infiltrate the soil. Land use can contribute to the volume of water reaching the river, in a similar way to clay soils. For example, rainfall on roofs, pavements , and roads will be collected by rivers with almost no absorption into
4176-432: 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. Prior to the construction of the first bridge in 1966, the channel was crossed by the Aust Ferry . Other notable bridges include: The Severn Tunnel , completed in 1886 by John Hawkshaw on behalf of the Great Western Railway , lies near
4248-446: The route taken by the Danes : "... Foron þa up be Temese oþþæt hie gedydon æt Sæferne , þa up be Sæferne . The Seafarer (poem) ..."þæt he a his sæfore sorge næbbe, to hwon hine Dryhten gedon wille." ..."that he never in his seafaring has a worry, as to what his Lord will do to him." — A passage in Old English poem The name Sæfern might be related to: The Old Norse name Sæfari ("Seafarer") lives on as
4320-501: The slope leading to the tunnel exit. A railway coach was provided for passengers and drivers. Reservations could be made and the fee for the car was about thirty shillings (£1.50) in the early 1950s. There have been many disasters on the Severn , which have claimed perhaps 300 lives, depending on sources, especially during the 20th century. The Severn Railway Bridge was badly damaged by the collision of two river barges in 1960, which led to its demolition in 1970. Five crew members of both
4392-420: 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
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#17327830302424464-418: The speed with which the runoff reaches a river. A long thin catchment will take longer to drain than a circular catchment. Size will help determine the amount of water reaching the river, as the larger the catchment the greater the potential for flooding. It is also determined on the basis of length and width of the drainage basin. Soil type will help determine how much water reaches the river. The runoff from
4536-536: The tidal river which is dangerous to navigate. The Stroudwater Navigation used to join the tidal Severn at Framilode , but since the 1920s has connected to the Severn only via the Gloucester and Sharpness Canal. The Lydney Canal is a short canal which connects Lydney to the river. The section of the river between Tewkesbury and Worcester forms part of the Avon Ring , a 109-mile (175 km) circular cruising route which includes 129 locks and covers parts of three other waterways. Paddle steamers were operated in
4608-415: The time taken for rain to reach the river, while catchment size, soil type, and development determine the amount of water to reach the river. Generally, topography plays a big part in how fast runoff will reach a river. Rain that falls in steep mountainous areas will reach the primary river in the drainage basin faster than flat or lightly sloping areas (e.g., > 1% gradient). Shape will contribute to
4680-477: The time taken for runoff water within a drainage basin to reach a lake, reservoir or outlet, assuming constant and uniform effective rainfall. Drainage basins are the principal hydrologic unit considered in fluvial geomorphology . A drainage basin is the source for water and sediment that moves from higher elevation through the river system to lower elevations as they reshape the channel forms. Drainage basins are important in ecology . As water flows over
4752-406: 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 . The river's course within Wales lies wholly within
4824-420: 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. 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
4896-405: 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
4968-405: 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,
5040-446: 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
5112-468: The world's land. Just over 13% of the land in the world drains to the Pacific Ocean . Its basin includes much of China, eastern and southeastern Russia, Japan, the Korean Peninsula , most of Indochina, Indonesia and Malaysia, the Philippines, all of the Pacific Islands , the northeast coast of Australia , and Canada and the United States west of the Continental Divide (including most of Alaska), as well as western Central America and South America west of
5184-703: Was the Aust Ferry , which closed in 1966 when the Severn Bridge opened. One of the Aust ferries, Severn Princess , is still in Chepstow although largely derelict. Currently the only passenger boat operating between Shrewsbury & Gloucester is the 'River King' vessel that operates in Stourport. Worcester River Cruises used to run boat trips up and down the river between Tewkesbury and Stourport, operating
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