Severn Estuary

Severn Estuary

The Severn Estuary ( _cy. Môr Hafren) is the estuary of the River Severn, the longest river in Great Britain. Its high tidal range means it has been at the centre of discussions in the UK regarding renewable energy.

Geography

In navigational and cartographical terms, the river becomes the Severn Estuary after the Second Severn Crossing near Severn Beach, South Gloucestershire and stretches to a line from Lavernock Point (south of Cardiff) to Sand Point near Weston-super-Mare. The estuary is about convert|2|mi|km wide at Aust, and about convert|9|mi|km|0 wide between Cardiff and Weston-super-Mare.

The estuary forms the boundary between Wales and England in this stretch. On the northern side of the estuary are the Caldicot and Wentloog Levels, on either side of the city of Newport; and, to the west, the city of Cardiff together with the resort of Penarth. On the southern, English, side, are Avonmouth, Portishead, Clevedon, and Weston-super-Mare. Denny Island is a small rocky island of convert|0.24|ha|acre|1|abbr=off, with scrub vegetation, approximately three miles north of Portishead. Its rocky southern foreshore marks the boundary between England and Wales, but the island itself is reckoned administratively to Monmouthshire, Wales.

The estuary has one of the highest tidal ranges in the world — about convert|15|m|ft|0. [cite web | url= http://www.environment-agency.gov.uk/commondata/acrobat/severnpositionmay2006_1508223.pd | format= PDF | work= UK Environment Agency | title= Severn Estuary Barrage | date= 31 May 2006 | accessdate= 2007-09-03 ] [cite web | url= http://www.bbc.co.uk/bristol/content/articles/2005/07/04/bristolchannel_feature.shtml | title= Coast: Bristol Channel | work= BBC | accessdate= 2007-08-27 ] During the highest tides, the rising water is funnelled up the estuary into the Severn bore, a self-reinforcing solitary wave that travels rapidly upstream against the river current. [cite web | url= http://www.environment-agency.gov.uk/regions/midlands/434823/ | publisher= Environment Agency | title= Severn Bore and Trent Aegir | accessdate= 2008-01-13] . The estuary's funnel shape, its tidal range, and the underlying geology of rock, gravel and sand, produce strong tidal streams and high turbidity, giving the water a notably brown coloration.

The tidal range also results in the estuary having one of the most extensive intertidal wildlife habitats in the UK, comprising mudflats, sandflats, rocky platforms and islands. These form a basis for plant and animal communities typical of extreme physical conditions of liquid mud and tide-swept sand and rock. The estuary is recognised as a wetland area of international importance and is designated as a Ramsar site. [ [http://www.jncc.gov.uk/pdf/RIS/UK11081.pdf Information on Severn Estuary Ramsar site designation] ]

West of the line between Lavernock Point and Sand Point is the Bristol Channel, which in turn discharges into the Celtic Sea and the wider Atlantic Ocean. The islands of Steep Holm and Flat Holm are located close to that line, in the middle of the estuary.

Sometimes the term Severn Estuary is used to refer to a geographically wider area stretching from Gloucester to west Wales and Devon, although the upstream stretch between Gloucester and Aust is more correctly called the River Severn, and the maritime stretch between Wales and the coast of Somerset and Devon is more correctly called the Bristol Channel.

Renewable energy

The Severn Estuary has the potential to generate more renewable electricity than all other UK estuaries. If harnessed, it could create up to 5% of the UK’s electricity, contributing significantly to the UK’s climate change goals as well as the European Union's renewable energy targets. [cite web | url= http://new.wales.gov.uk/topics/environmentcountryside/energy/severntidal/?lang=en | publisher= Welsh Assembly Government | title= Severn Tidal Power| accessdate= 2008-09-01] . A Severn tidal power feasibility study is, in 2008, currently being undertaken by the UK Government to assess all tidal range technologies (including barrages, lagoons and others). The study will look at the costs, benefits and impacts of a Severn tidal power scheme and will help Government decide whether it could or could not support such a scheme.

evern Estuary Partnership

The Severn Estuary Partnership (SEP) was set up in 1995 as an independent initiative to focus the activities of local government, statutory authorities and interested parties such as farmers and fisherman. Its stated aim is "To bring together all those involved in the development, management and use of the Estuary within a framework which encourages the integration of their interests and responsibilities to achieve common objectives".cite web | url= http://www.severnestuary.net/sep/pdfs/sesengli.pdf | format= PDF | title= Strategy for the Severn Estuary (English language summary) | work= The Severn Estuary Partnership | accessdate= 2007-12-24] In 2001 SEP published the "Strategy for the Severn Estuary", which sets out a plan for the management of the estuary.

SEP uses a geographically extended definition of the Severn Estuary, beginning at the tidal limit of the River Severn in Gloucester and ending at a line drawn between Hurlestone Point near Minehead and Nash Point in the Vale of Glamorgan.

ee also

*Severnside
*Severn Barrage
*Severn Tidal Power Feasibility Study

References

External links

* [http://www.severnestuary.net The Severn Estuary Partnership]


Wikimedia Foundation. 2010.

Игры ⚽ Поможем сделать НИР

Look at other dictionaries:

  • MXR Severn Estuary — is a regional commercial digital radio multiplex in the United Kingdom, which serves the West of England and South Wales, including Bristol, Bath, Weston super Mare, Cardiff, Newport, Swansea, the South Wales Valleys and north Somerset. tations… …   Wikipedia

  • Severn Tidal Power Feasibility Study — is the name of a UK Government project looking at the possibility of using the huge tidal range in the Severn Estuary and Bristol Channel to generate electricity. The tidal range in the Severn Estuary is the second highest in the world and can… …   Wikipedia

  • Severn crossing — is a term used to refer to the two motorway crossings over the River Severn estuary between England and Wales. The two crossings are: *The Severn Bridge (Welsh: Pont Hafren ) *The Second Severn Crossing (Welsh: Ail Groesfan Hafren ) The first… …   Wikipedia

  • Severn Barrage — The Severn Barrage is the name of a number of ideas for building a barrage from the English coast to the Welsh coast over the Severn tidal estuary. Ideas for damming or barraging the Severn estuary (and Bristol Channel) have existed since the… …   Wikipedia

  • Severn Bridge — Infobox Bridge bridge name=Severn Bridge caption=The Severn Bridge seen from the English side of the river. From 1966 to 1996, the bridge carried the M4 motorway. On completion of the Second Severn Crossing the motorway from Olveston on the… …   Wikipedia

  • Severn, River — Welsh Hafren ancient Sabrina River, eastern Wales and western England. Britain s longest river, it is 180 mi (290 km) long from its source to tidal waters. It rises in east central Wales and crosses the English border near Shrewsbury, continuing… …   Universalium

  • Severn Valley (England) — Location map United Kingdom lat=52.45 long= 2.36 width=180 float=right caption= Severn Valley shown within the United Kingdom (gbmapping|SO750840)The Severn Valley is a rural area of mid western England, through which the River Severn runs and… …   Wikipedia

  • Severn Beach Line — The Severn Beach Line is a local railway in Bristol, UK. It runs from Narroways Hill Junction to Severn Beach, and is the successor to the Bristol Port Railway and Pier, which ran from a Bristol terminus in the Avon Gorge to a station and pier on …   Wikipedia

  • Severn Valley (Cthulhu Mythos) — The Severn Valley is the setting of several fictional towns and other locations created by horror writer Ramsey Campbell. Part of the Cthulhu Mythos started by H. P. Lovecraft, the fictional milieu is arguably the most detailed mythos setting… …   Wikipedia

  • Severn Way — The Severn Way [http://www.geograph.org.uk/photo/85902] is a waymarked [http://www.geograph.org.uk/photo/6687] long distance footpath in the United Kingdom following the course of the River Severn [http://www.geograph.org.uk/photo/118846] in the… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”