The River Misbourne rises in a field on the outskirts of
Great Missenden in
Buckinghamshire
Buckinghamshire (, abbreviated ''Bucks'') is a Ceremonial counties of England, ceremonial county in South East England and one of the home counties. It is bordered by Northamptonshire to the north, Bedfordshire to the north-east, Hertfordshir ...
, passing through
Little Missenden, Old
Amersham
Amersham ( ) is a market town and civil parish in Buckinghamshire, England, in the Chiltern Hills, northwest of central London, south-east of Aylesbury and north-east of High Wycombe. Amersham is part of the London commuter belt.
There ar ...
,
Chalfont St Giles,
Chalfont St Peter and under the
Chiltern railway line and the
M25 motorway to its
confluence
In geography, a confluence (also ''conflux'') occurs where two or more watercourses join to form a single channel (geography), channel. A confluence can occur in several configurations: at the point where a tributary joins a larger river (main ...
with the
River Colne just north of where the Colne is crossed by
Western Avenue, the
A40 road. It falls by around in the course of its length.
Etymology
The name ''Misbourne'' is first attested, in the form ''Misseburne'', in 1407. The ''-bourne'' element is agreed to derive from
Old English
Old English ( or , or ), or Anglo-Saxon, is the earliest recorded form of the English language, spoken in England and southern and eastern Scotland in the Early Middle Ages. It developed from the languages brought to Great Britain by Anglo-S ...
''burna'' ('stream, river'), but the etymology of the first element is uncertain. It is thought to occur in the names of both
Great
Great may refer to:
Descriptions or measurements
* Great, a relative measurement in physical space, see Size
* Greatness, being divine, majestic, superior, majestic, or transcendent
People
* List of people known as "the Great"
* Artel Great (bo ...
and
Little Missenden, and also in the
Tring place-name
Miswell.
Frank Stenton and
Allen Mawer guessed that it came from a hypothetical Anglo-Saxon personal name ''Myrsa'', which they also supposed to be found in the name of
Mursley.
Eilert Ekwall suggested that it came from a lost Old English word related to English ''moss'', and to Danish ''mysse'' and Swedish ''missne'' (which denote plants of the genus ''
Calla'', such as water arum). Recent researchers have tentatively preferred Ekwall's guess, in which case the name ''Misbourne'' would once have meant something like 'river where water-plants/marsh-plants grow'.
[A. D. Mills, ''A Dictionary of English Place Names'' (Oxford: Oxford University Press, 1991), p. 330.]
History
In 1906 the
Great Western Railway (GWR) constructed the
Chalfont Viaduct to carry trains between London and across the river. In the mid-1980s, when the M25 was being constructed, the Misbourne was diverted under the motorway via underground concrete
culvert
A culvert is a structure that channels water past an obstacle or to a subterranean waterway. Typically embedded so as to be surrounded by soil, a culvert may be made from a pipe (fluid conveyance), pipe, reinforced concrete or other materia ...
s. The route of the motorway was then aligned to pass through the arches of the Chalfont Viaduct.
Flow
The river flows over a bed of impermeable material on top of a porous substrate. This state is only quasi-stable since in periods of low rainfall the water table drops below the level of the impermeable layer. If groundworks are then carried out which damage this layer, the river can sink into the porous substrate and disappear.
The Misbourne has had intermittently reduced or stopped-flow due to abstraction for domestic supply from the
aquifer
An aquifer is an underground layer of water-bearing material, consisting of permeability (Earth sciences), permeable or fractured rock, or of unconsolidated materials (gravel, sand, or silt). Aquifers vary greatly in their characteristics. The s ...
s feeding it. This has caused its course to be neglected to lead to partial obstruction. When the water company undertook remedial measures to restore the flow, there were episodes of flooding in both Chalfont St Peter and Chalfont St Giles. Subsequent work has restored the integrity of the course. The upper part of the river was dry for over 3 years starting in November 2003 but re-appeared in February 2007 following several months of above-average rainfall which raised the water table.
Misbourne starts flowing again (Bucks Free Press article)
/ref>
References
External links
{{DEFAULTSORT:Misbourne, River
1Misbourne
Rivers of Buckinghamshire
Amersham