Water quality
The Environment Agency measure water quality of the river systems in England. Each is given an overall ecological status, which may be one of five levels: high, good, moderate, poor and bad. There are several components that are used to determine this, including biological status, which looks at the quantity and varieties of invertebrates, angiosperms and fish, and chemical status, which compares the concentrations of various chemicals against known safe concentrations. Chemical status is rated good or fail. [4]
Water quality of the River Asker in 2016:
| Section | Ecological
Status | Chemical
Status | Overall
Status | Length | Catchment | Channel |
|---|
| Asker [5] | Poor | Good | Poor | 11.796 km (7.330 mi) | 23.699 km2 (9.150 sq mi) | |
| Mangerton Brook [6] | Good | Good | Good | 13.378 km (8.313 mi) | 25.484 km2 (9.839 sq mi) | |
|
The River Leam, anciently Leame, etc, is a river in England which rises at Hellidon Hill in Northamptonshire then flows through Warwickshire, including the town of Leamington Spa, named after it. It then flows into the River Avon near Warwick, and thence into the River Severn. The name is first recorded in 956 as Limenan, and derives from British Lemanā, meaning "elm-tree river".
The River Churn is a tributary of the River Thames in central England. It rises at Seven Springs in Gloucestershire and flows south for approximately 37.3 km (23.2 mi) to meet the Thames at Cricklade in Wiltshire. Its length from its source to the confluence with the Thames is greater than that of the Thames from Thames Head, though the Churn is regarded as a tributary rather than the main river.
The Holy Brook is a channel of the River Kennet that flows through the English town of Reading. While of considerable historical significance, the origin and nature of the brook is still unclear. It is probable that some parts of the channel are natural, while other parts were created in mediaeval times by the monks of Reading Abbey to supply water mills and fish ponds. John Speed's map of Reading (c.1610) shows the brook flowing in the open air throughout, but a map from 1835 shows the town centre section to have been largely culverted by then, as is the case now.
The River Itchen flows through east Warwickshire in England. It is a small river, about 18 miles (29 km) long, and its general course is from south to north.
The River Allen is a river in the county of Dorset in South West England. It flows for 14 miles (23 km) and has its confluence with the River Stour in Wimborne Minster. It has two main tributaries, the Gussage Stream and the Crichel Stream.
The River Coln is a river in Gloucestershire, England. It rises to the north of Brockhampton, a village to the east of Cheltenham, and flows in a south/south-easterly direction through the Cotswold Hills via Andoversford, Withington, Fossebridge, Bibury, Coln St Aldwyns, Quenington and Fairford. It joins the River Thames to the south-west of Lechlade, where it shares a confluence with the Thames and Severn Canal, by The Round House Footbridge.
The River Tawd flows through Skelmersdale and Lathom in West Lancashire.
The River Salwarpe is a 20.4 miles (32.8 km) long river in Worcestershire, England. It is a left bank tributary of the River Severn, which it joins near Hawford.
The Rye is a stream rising east of Ashtead and flowing into the River Mole near Leatherhead, Surrey.
This River Blackwater drains small parts of the English counties of Hampshire and Wiltshire. It is a tributary of the River Test.
The River Anton is a chalk stream in Hampshire in south east England. It rises in Andover and flows southwards for approximately 8 miles (13 km) to meet the River Test near Chilbolton. The principal tributary of the Anton, the Pillhill Brook, joins the river at Upper Clatford.
The Emm Brook, sometimes known as the Embrook or Emmbrook, is a small river in the English county of Berkshire. It is a tributary of the River Loddon which it meets at the village of Hurst.
The River Nadder is a tributary of the River Avon, flowing in south Wiltshire, England.
The River Lostock is a river in Lancashire, England.
The River Doe Lea is a river which flows near Glapwell and Doe Lea in Derbyshire, England. The river eventually joins the River Rother near Renishaw. The river contained 1,000 times the safe level of dioxins in 1991, according to a statement made by Dennis Skinner, (MP) in the House of Commons in 1992. The river flows through the site of the former Coalite plant near Bolsover, where coke, tar and industrial chemicals were manufactured until the plant closed in 2004.
The River Slea is a tributary of the south branch of the River Wey in Hampshire.
The Corfe River is one of the four main rivers flowing into Poole Harbour in the county of Dorset, England. It is just under 9 kilometres long.
Pilhill Brook is a 9.9-kilometre-long (6.2 mi) tributary of the River Anton in Hampshire, England. It is a chalk stream, known for its trout fishing.
The River Sem is a natural waterway that flows through the ceremonial county of Wiltshire in England. It flows approximately 4+1⁄4 miles (7 km) from its source near East Knoyle to join the River Nadder near Wardour.
The Mangerton River or Mangerton Brook is a 13.37 km long river in Dorset, England that is a tributary of the River Asker. The river rises at Powerstock and flows westward through the small village of West Milton, then southward through the hamlet Mangerton, before flowing into the River Asker at Bradpole, near Bridport, which itself flows into the River Brit. It also flows through the West Dorset Alder Woods protected area.
