Site of Special Scientific Interest | |
Location | Greater London Buckinghamshire |
---|---|
Grid reference | TQ043896 |
Interest | Biological |
Area | 132.0 hectares |
Notification | 1985 |
Location map | Magic Map |
Mid Colne Valley is a 132 hectare biological Site of Special Scientific Interest in Harefield in the London Borough of Hillingdon and Denham in South Buckinghamshire. Its main importance lies in its extensive diversity of birdlife in lakes in former gravel pits.
The site is divided into three areas. The great majority is in an area of four lakes bounded on the west by the River Colne and on the east by the Grand Union Canal. The river forms the boundary between Greater London to the east and Buckinghamshire to the west, and west of the river in Denham is a small area called Ranston Covert. The SSSI also includes a field called Coppermill Down east of the canal. [1] [2]
The main area of the site is called Broadwater Lake after its principal body of water, and it is part of the Colne Valley regional park. The lakes were created by dredging for sand and gravel between the 1960s and the 1980s. [3] To the south is Korda Lake, and then to the north of it Harefield Lake next to the Grand Union Canal, with Long Pond adjacent to it by the river. North again is Broadwater Lake, which at 80 hectares occupies over half the entire SSSI. Natural England regards the condition of the area as 'favourable'. [4] [5]
Korda Lake, Long Pond, the River Colne and the western side of Broadwater Lake form the Broadwater Lake nature reserve, which is managed by the Hertfordshire and Middlesex Wildlife Trust. [6] Harefield Lake is private land owned by an aggregates company, and silting caused by aggregate washing is a matter of concern to Natural England. [5] The lakes are used for fishing, but this is prohibited between 15 March and 15 June to prevent damage to the SSSI. [7] [8]
Broadwater Lake is unusual in having a number of small islands. It is significant for its breeding wetland birds and over-wintering water birds. Wintering birds which are present in nationally important numbers are great crested grebes, cormorants, shovellers and tufted ducks, and the number of gadwalls is internationally significant. The River Colne is important for bats, particularly Daubentons. [6] The area also has ancient woodland. [9]
There is access from Moorhall Road close to the Colne River bridge.
Ranston Covert in Denham is the only part of the site in Buckinghamshire. It was formerly a separate SSSI. [2] It is a 26 hectare area of woodland and scrub between the Colne River and Denham Way. It has a variety of breeding birds and its status is described as favourable. [10]
The SSSI includes a 6 hectare field east of the Grand Union Canal described in the Natural England citation as Coppermill Down, although it is not known by that name locally. It is one of the few remaining examples of unimproved chalk grassland in Greater London, and is notable for the pyramidal orchid and the bee orchid. [2] Its status in September 2011 was described as 'unfavourable declining' due to inadequate grazing. [11] The field is crossed by a footpath between Jacks Lane and Park Lane. [12]
Proposed high speed railway High Speed 2 between, initially, London and the Midlands if built will cut across a corner of the site on a viaduct. Natural England commented that there would be a serious loss of ancient woodland and a potentially damaging indirect impact on Broadwater Lake. [9]
Wikimedia Commons has media related to Mid Colne Valley . |
Denham is a village and civil parish in the unitary authority of Buckinghamshire, England, approximately 17 miles (27 km) from central London, 2 miles (3 km) northwest of Uxbridge and just north of junction 1 of the M40 motorway. The name is derived from the Old English for "homestead in a valley". It was listed in the Domesday Book of 1086 as Deneham. Denham contains the Buckinghamshire Golf Club.
The River Blackwater is a tributary of the Loddon in England and sub-tributary of the Thames. It rises at two springs in Rowhill Nature Reserve between Aldershot, Hampshire and Farnham, Surrey. It curves a course north then west to join the Loddon in Swallowfield civil parish, central Berkshire. Part of the river splits Hampshire from Surrey; a smaller part does so as to Hampshire and Berkshire.
The Colne is a river and a tributary of the River Thames in England. Just over half its course is in south Hertfordshire. Downstream, it forms the boundary between the South Bucks district of Buckinghamshire and the London Borough of Hillingdon. The confluence with the River Thames is on the Staines reach at Staines-upon-Thames.
The Cotswold Water Park is the United Kingdom's largest marl lake system, straddling the Wiltshire–Gloucestershire border, northwest of Cricklade and south of Cirencester. There are 180 lakes, spread over 42 square miles (110 km2).
Walthamstow Marshes, is a 36.7 hectare biological Site of Special Scientific Interest in Walthamstow in the London Borough of Waltham Forest. It was once an area of lammas land – common land used for growing crops and grazing cattle.
Maple Cross is a village in Hertfordshire, England, which up until the Second World War consisted of an inn, a blacksmith's shop and a few cottages. Today there are around 800 postwar council houses. Some of these have been sold into private ownership. The area is close by junction 17 of the M25 motorway, which makes up the western boundary of the village. It lies on the western fringe of Rickmansworth, about 8 kilometres (5.0 mi) west of Watford and 6 miles north of Uxbridge.
Bowdown and Chamberhouse Woods is a 67.9-hectare (168-acre) biological Site of Special Scientific Interest south of Thatcham in Berkshire. An area of 55 hectares is a nature reserve managed by the Berkshire, Buckinghamshire and Oxfordshire Wildlife Trust.
Sulham and Tidmarsh Woods and Meadows is a 75.7-hectare (187-acre) biological Site of Special Scientific Interest west of Reading in Berkshire.
The Colne Brook is a river in England that is a distributary of the River Colne which runs from Uxbridge Moor, there forming the western border of Greater London, to the River Thames just below Bell Weir Lock in Hythe End, Wraysbury, Berkshire.
The Colne Valley Regional Park is 43 square miles (110 km2) of parks, green spaces and reservoirs alongside the often multi-channel River Colne and parallel Grand Union Canal, mainly in Hertfordshire and Buckinghamshire, with parts in the London Borough of Hillingdon, Berkshire and a small area in Surrey.
Old Park Wood is a 16.7-hectare (41-acre) Site of Special Scientific Interest in Harefield in the London Borough of Hillingdon. The south-east part is an 8-hectare (20-acre) nature reserve owned and managed by the Hertfordshire and Middlesex Wildlife Trust.
Frays Farm Meadows is a 28.2-hectare (70-acre) biological Site of Special Scientific Interest near Denham in the London Borough of Hillingdon. It was notified as an SSSI in 1981, and has been managed by the London Wildlife Trust on behalf of Hillingdon Council since 1999. It is part of the Colne Valley Regional Park.
Denham Lock Wood is a 6.3-hectare (16-acre) biological Site of Special Scientific Interest (SSSI) next to the Grand Union Canal, and near Denham in the London Borough of Hillingdon. It was notified in 1986 and is managed by the London Wildlife Trust on behalf of Hillingdon Council. It lies within the Colne Valley Regional Park.
Lower Wye Gorge is a 65-hectare (160-acre) biological and geological Site of Special Scientific Interest in Gloucestershire, notified in 1954 and renotified 1987. The site includes two Gloucestershire Wildlife Trust nature reserves being Ban-y-gor Wood and Lancaut. The Natural England citation states a revision for Lancaut inclusion.
The Hudnalls is a 94.4-hectare (233-acre) biological Site of Special Scientific Interest in Gloucestershire, notified in 1972. The site is listed in the 'Forest of Dean Local Plan Review' as a Key Wildlife Site (KWS).
Denham Country Park is a 69-acre public park and Local Nature Reserve in Buckinghamshire and the London Borough of Hillingdon. It is part of the 42 square mile Colne Valley Regional Park, and the Colne Valley Park Visitor Centre and cafe are located in Denham Country Park.
Rickmansworth Aquadrome is a 41 hectares public park and Local Nature Reserve in Rickmansworth in Hertfordshire. It is owned and managed by Three Rivers District Council.
Dancersend is an 81.3 hectare Site of Special Scientific Interest (SSSI) south of Aston Clinton in Buckinghamshire. Part of the site is managed by the Forestry Commission and part by the Berkshire, Buckinghamshire and Oxfordshire Wildlife Trust (BBOWT). The BBOWT's 47 hectare nature reserve, called Dancersend with Pavis Woods, extends into fields west of the SSSI. It is in the Chilterns Areas of Outstanding Natural Beauty.