The River Parrett flows through the counties of Dorset and Somerset in South West England, from its source in the Thorney Mills springs in the hills around Chedington in Dorset. Flowing northwest through Somerset and the Somerset Levels to its mouth at Burnham-on-Sea, into the Bridgwater Bay Nature Reserve on the Bristol Channel, the Parrett drains an area of 643 sq mi (1,670 km2)—about 50 per cent of Somerset's land area.
The Parrett's main tributaries include the Rivers Tone, Isle, and Yeo, and the River Cary via the King's Sedgemoor Drain. The 37-mile (60 km) long river is tidal for 27 miles (43 km) up to Oath. Because the fall of the river between Langport and Bridgwater is only 1 foot per mile (0.2 m/km), it is prone to frequent flooding in winter and during high tides. Many approaches have been tried since the early 19th century to reduce the incidence and effect of floods and to drain the surrounding fields.
During the Roman era the river was crossed by a ford, and in Anglo-Saxon times formed a boundary between Wessex and Dumnonia. From the medieval period the river served the Port of Bridgwater, enabling cargoes to be transported inland. The arrival of the railways led to a decline and commercial shipping now only docks at Dunball. Man's influence on the river has left a legacy of bridges and industrial artefacts. The Parrett along with its connected waterways and network of drains supports an ecosystem that includes several rare species of flora and fauna. The River Parrett Trail has been established along the banks of the river. (Full article...)