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Bay in Bristol Channel

Bridgwater Bay is on the Bristol Channel, north of Bridgwater in Somerset, England at the mouth of the River Parrett and the end of the River Parrett Trail. It stretches from Minehead at the southwestern end of the bay to Brean Down in the north. The area consists of large areas of mudflats, saltmarsh, sandflats and shingle ridges, some of which are vegetated. It has been designated as a Site of Special Scientific Interest (SSSI) covering an area of since 1989, and is designated as a wetland of international importance under the Ramsar Convention. The risks to wildlife are highlighted in the local Oil Spill Contingency Plan. Several rivers, including the Parrett, Brue and Washford, drain into the bay. Man made drainage ditches from the Somerset Levels, including the River Huntspill, also run into the bay. The mud flats provide a habitat for a wide range of flora and fauna. These include some nationally rare plants, beetles and snails. It is particularly important for overwintering waders and wildfowl, with approximately 190 species recorded including Eurasian whimbrel (Numenius phaeopus), black tailed godwit (Limosa limosa), dunlin (Calidris alpina) and wigeon (Anas penelope). Fishing has taken place using shallow boats, known as flatners, and fixed wooden structures for hundreds of years. It was also the last site in England used for 'mudhorse fishing'. There are several small harbours along the coast. The low lying areas of the bay have been subject to flooding, including the Bristol Channel floods of 1607 and many times since particularly around the Steart Peninsula. In response to this threat sea walls have been built at several points including at Burnham on Sea, Berrow and Blue Anchor to Lilstock Coast. The extensive mud flats and high tidal range have been the cause of several drownings and rescue services are now provided by the Burnham Area Rescue Boat.

Bridgwater Bay forms a portion of the coastline of Somerset on the southern side of the Bristol Channel stretching from the Quantock Hills at the south western end to Brean Down at the northern end. Around the coastline is a wave cut platform of Jurassic Blue Lias. Several rivers flow into the bay, the main ones being the Parrett, Brue and Washford, along with the man made River Huntspill. Major features and settlements along the coastline, running from north east to south west, include: Brean, Berrow, Burnham on Sea, the mouth of the River Parrett, the Steart Peninsula, Lilstock, East Quantoxhead and Watchet. Sand dunes at Berrow and a shingle ridge at Steart have been created by winds blowing from the west. On the beach near Stogursey are the remains of a submerged forest dated to 2500 B. C. 6500 BC. Brean Down is a promontory marking the eastern end of the bay. Made of carboniferous limestone, it is a continuation of the Mendip Hills, and two further continuations are the small islands of Steep Holm and Flat Holm. It is owned by the National Trust, and is rich in wildlife, history and archaeology, as well as being a Site of Special Scientific Interest in its own right. It is bounded by steep cliffs and, at its seaward point, Brean Down Fort built in 1865 and then re armed in the Second World War. There is evidence of an Iron Age hill fort, prehistoric barrows, field systems and a pagan shrine. The shrine dating from pre Roman times was re established as a Romano Celtic style temple in the mid 4th century and probably succeeded by a small late 4th century Christian oratory. In 1897, following wireless transmissions from Lavernock Point in Wales to Flat Holm, Guglielmo Marconi moved his equipment to Brean Down and set a new distance record for wireless transmission. At low tide large parts of the bay become mud flats wide, due to the tidal range of , second only to the Bay of Fundy in Eastern Canada. The intertidal mud flats are, as a result, potentially dangerous and it is not uncommon for the emergency services to mount rescue operations on them. Following the death of Lelaina Hall off Berrow in 2002, a local fund raising campaign succeeded in purchasing a Swedish built BBV6 rescue hovercraft. The hovercraft is operated by Burnham Area Rescue Boat (BARB) in Burnham on Sea. Much of the coastline within the western part of the reserve is accessible via a waymarked public footpath, and the South West Coast Path begins at Minehead at the western end of the bay. The tidal range holds potential for energy generation and plans for a tidal barrage in the bay have been considered. Hinkley Point is a headland extending into Bridgwater Bay 5 mile (8 km) west of Burnham on Sea, close to the mouth of the River Parrett. The landscape of Hinkley Point is dominated by two nuclear power stations: Hinkley Point A Magnox (now closed) and Hinkley Point B AGR. A third, twin unit European Pressurized Reactor (EPR) reactor is planned, and will become Hinkley Point C.

Man made sea defenses include a sea wall at Burnham on Sea and a section south from Brean Down. There are also sand dune belts which are managed for their protective function and as a wildlife habitat. There are some concerns that the proposed Severn Barrage could leave some sites high and dry, and others permanently under water. The foreshore at Watchet, which lies at the mouth of the Washford River, and on the edge of Exmoor National Park, is rocky, but has a small harbour. The cliffs between Watchet and Blue Anchor show a distinct pale, greenish blue colour, resulting from the coloured alabaster found there. The name "Watchet" or "Watchet Blue" was used in the 16th century to denote this colour. East Quantoxhead used to have a small harbour which brought in limestone for local limekilns and exported alabaster. It is thought that it was also used for smuggling. At Kilve are the remains of a red brick retort, built in 1924, when it was discovered that the shale found in the cliffs was rich in oil. The beach is part of the Blue Anchor to Lilstock Coast SSSI (Site of Special Scientific Interest). Along this coast the cliffs are layered with compressed strata of oil bearing shale and blue, yellow and brown lias embedded with fossils. In 1924 Forbes Leslie founded the Shaline Company to exploit them. This retort house is thought to be the first structure erected here for the conversion of shale to oil but the company was unable to raise sufficient capital and this is now all that remains of the anticipated Somerset oil boom.

The intertidal mud flats of the bay have a long history of use for fishing, with structures on Stert Flats being dated by dendrochronological analysis to between 932 and 966. Catches include: Thinlip mullet, plaice, dogfish, cuttlefish, skate, shrimp, prawns, sea bass, and sole. Watchet Boat Museum displays the unusual local flatner boats which were used for fishing in the bay, along with associated artefacts.

At low tide extensive areas of mudflats (the Steart and the Berrow Flats) are exposed, providing important feeding and overwintering grounds for waders (shorebirds). Invertebrate fauna including six nationally rare species and eighteen nationally scarce species can be found in the ditches and ponds around the shores. Some of the potential risks to wildlife are highlighted in the local Oil Spill Contingency Plan. It is also a Nature Conservation Review Grade 1* site, meaning it is included in Derek Ratcliffe's book listing the most important places for nature conservation in Great Britain. The Spartina is generally shorter in the bay than at other sites due to the high tides and the turbidity of the water, reaching around as opposed to elsewhere. On higher ground common saltmarsh grass (Puccinellia maritima) can be found along with sea aster (Aster tripolium). Where the land is ungrazed, common reed (Phragmites australis) often forms a zone above the sea aster. Where the upper marsh is grazed by cattle red fescue (Festuca rubra) and creeping bent (Agrostis stolonifera) are found. The area of marsh furthest from the sea supports Sea couch (Agropyron pungens) and sea club rush (Scirpus maritimus). Some of the broomrapes growing near Bridgwater Bay, which were originally thought to be oxtongue broomrape (Orobanche artemisiae campestriae), are now no longer believed to be this species, but atypical specimens of ivy broomrape (Orobanche hederae) Other plants on the southern slopes include the Somerset hair grass, wild thyme, horseshoe vetch and birds foot trefoil. In early winter the wigeon select Puccinellia maritima in preference to Agrostis stolonifera and Festuca rubra. Avocets have become regular autumn and winter visitors to the area in recent years, favouring the lower reaches of the River Parrett, The birds seen on Brean Down include peregrine falcon, western jackdaw, kestrel, collared and stock doves, common whitethroat, linnet, stonechat, dunnock and rock pipit. There are also several species of butterfly, including chalkhill blue, dark green fritillary, meadow brown, marbled white, small heath, and common blue.