River Ash, Surrey

River Ash
Reach with wider banks, reeds and woodland close to Shepperton Studios
The southernmost inner west-east line marks the end of the river, the rest is wholly in the same Borough shown.
Location
Country/NationUnited Kingdom
Region/CountryEngland
CountySurrey
CitySunbury-on-Thames, Shepperton, Littleton 51°24′25″N 0°28′08″W / 51.407°N 0.469°W / 51.407; -0.469, Laleham, Ashford, Staines-upon-Thames
Physical characteristics
SourceSluice against lower River Colne
  locationStaines-upon-Thames, Spelthorne, England, United Kingdom
  elevation14 m (46 ft)
MouthRiver Thames
  location
Sunbury-on-Thames and Shepperton, Spelthorne, England, United Kingdom
  elevation
8.6 m (28 ft)
Length10 km (6.2 mi)
Width 
  minimum2 feet (0.61 m)
  average6 feet (1.8 m)
  maximum20 feet (6.1 m)
Depth 
  minimum0.5 feet (0.15 m)
  average1.5 feet (0.46 m)
  maximum5 feet (1.5 m)
Basin features
ProgressionColneAshThames
Artificial extra source: outflow of un-useable water from fresh waterworks
River Ash and North Thames Reservoirs
Thames
1.
2.
Intake of aqueduct (with sluice)
Colne Brook
County or Shire Ditch
Wraysbury River
Colne (feeder of the three above)
Ash
Pumping Station to 3. & 4. & 5.
overflow sluice to the Ash
Gravity-drained aqueduct
A308 road
(River Ash under aqueduct)
A308 road
Pumping Station to 6.
Ashford Treatment Works for 6.
A244 road
Kempton Treatment Works
(some water sent directly to below)
7.Grand Junction Reservoir
Hampton Treatment Works
8.
Thames

The River Ash is a small, shallow river in Surrey, England. Its course of 10 kilometres (6.2 mi) is just outside Greater London. Work has been carried out to re-align, clear and build up a small, Littleton head of water and create two backwaters. One backwater dates to the medieval period; the other to the 1990s. It flows as one of the six distributaries of the River Colne from the south of Staines Moor immediately south of the Staines Bypass eastwards through the rest of the borough of Spelthorne before meeting the River Thames.

It is not navigable to craft and is rich in plant and insects, particularly reeds, diverse sedges (many of which commonly called bulrushes), pond-skaters, amphibians and lepidoptera (moths and butterflies). It enhances the Ash Link Nature Reserve, Studios Walk woodland biodiversity site and two parks. It is recognised as a key ecological feature within its borough.