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About the Severn Estuary

The Severn Estuary is one of the largest estuaries in Europe, covering the upper reaches of the Bristol Channel on the west coast of Britain, between South Wales and the South West of England. It is where the River Severn, Britain’s longest river, meets the sea in the form of an extended funnel that creates the largest tidal range in Europe and the 2nd highest in the world, with the maximum recorded range of 14.7m recorded at Avonmouth near Bristol.
As well as forming the border between England and Wales, the Severn Estuary is a habitat for migratory birds of European importance. In recognition of this the Estuary was classified as a Special Protection Area (SPA) in 1995. It is also a Ramsar site and was designated as a Special Area of Conservation (SAC) in December 2009. Where a SPA, such as the Severn Estuary, or Special Area of Conservation (SAC) incorporate subtidal and/or intertidal areas, they are referred to as European Marine Sites (EMS).
The SPA and SAC designations cover the intertidal and subtidal areas eastwards of a line between Lavernock Point on the Welsh coast and Brean Down on the English coast.
Due to the funnel shape and tidal range of the estuary, during the highest tides the rising water is funnelled up the estuary as the spectacular natural phenomenon of the Severn bore, a large surge wave that travels rapidly upstream against the river current, and is one of the biggest examples of a bore in the world.

The huge high tidal range of the Severn estuary means it has long been the focus of finding ways to harness its tidal energy as it has the potential to generate as much a 5% of the Britain’s electricity needs, contributing significantly to UK climate change goals and European Union renewable energy targets.
In January 2008 the Government launched a feasibility study to consider whether it could support a tidal power project in the Severn Estuary and, if so, on what terms. It’s most recent conclusions are that there is not a strong enough strategic case to proceed at this time and that, whilst potentially playing a role in the future, it is unlikely to be considered again before 2015.
The Severn Estuary has long been the focus of internationally important sea trade and port activities. John Cabot sailed through the estuary on his 1497 discovery of parts of North America at a time when Bristol was the second-largest seaport in England.

In the 18th and 19th centuries, the estuary helped supply the world during the industrial revolution, when Cardiff was one of the largest ports in the world and the world’s largest supplier of coal, as well as Britain’s largest exporter of iron.
Currently, the Port of Bristol is one of the Britain’s largest and fastest growing ports and is developing its role as a gateway container port for the UK and as a transshipment point for the Atlantic seaboard and Europe. It already utilises a deep water channel in the Severn estuary and has recently been given consent by the Department for Transport to expand its facilities with a new deep sea container terminal (DSCT) in the Bristol Channel. This terminal would be designed to be able to service future generations of ultra large container ships (ULCS) when they enter service.

For further information about the Severn Estuary:

Severn Estuary Partnership:
Set up in 1995, the Severn Estuary Partnership is an independent, estuary-wide NON-statutory initiative initiative led by local authorities and statutory agencies. We work with all those involved in the management of the estuary, from planners to port authorities, fishermen to farmers and many more with an interest in the future of the estuary.

Association of Severn Estuary Relevant Authorities:
ASERA (the Association of Severn Estuary Relevant Authorities) are the statutory organisations (Relevant Authorities) around the Severn Estuary that came together to collectively manage their activities on the Severn Estuary European Marine Site. In addition to general management and regulatory functions, many relevant authorities are also competent authorities and have statutory functions to make decisions on applications for consents, authorisations, licences and permits as governed by statute for European sites.

Severn Estuary Coastal Group:
The Severn Estuary Coastal Group (SECG) works to promote sustainable shoreline management, and to facilitate the duties and responsibilities of local authorities and other organisations managing coastal protection & flood defence issues around the Severn Estuary.
The area covered by the group spans from Lavernock Point in Wales to Anchor Head and Haw Bridge in England.
The Severn Estuary Coastal Group was formed in 1993 initially to deal with the preparation and completion of the first Shoreline Management Plan for the Estuary area from upstream of Lavernock Point west of Cardiff and Brean Down in Somerset.

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