Grimsbury Reservoir is owned by Thames Water and was built in in the early 1960s. It is the second largest raw water storage reservoir in Oxfordshire, with Farmoor being the largest. In comparison to Farmoor, it is similar in construction and the habitat it provides for birds but is on a much smaller scale. Essentially it is a large concrete lined bowl!
The reservoir has a surface area of circa 7.4 hectares, is around 8 feet deep and has shallow sloping banks. There are no islands or aquatic vegetation around the reservoir, so the habitat isn't particularly valuable to birds. However, like all water habitats it attracts birds to it - particularly birds on migration. The reservoir is used for various recreational activities like sailing, fishing, walking and of course - bird watching.
To the west of the reservoir are two pasture fields with a large hedge with mature trees separating them. These fields are also owned by Thames Water and are leased out to a farmer to graze cattle. They are heavily improved and are not of huge value to wildlife but birds do use them. The hedge in particular is a favoured location for migratory birds.
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| Courtesy and copyright of Mike Pollard |
Grimsbury Woodland Nature Reserve
The woodland is on land owned by Thames Water, just to the north east of the reservoir. It is a 3.5 hectare site of Scots Pine and Alder with other trees and scrub, originally planted by the Forestry Commission.
It is now managed as a nature reserve by the Banbury Ornithological Society and increases the bird and wildlife habitat and diversity in the area. It is being managed to improve it's current and keep its long term benefit to wildlife. Recently bird and bat boxes have been put up to increase its conservation value.
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| Courtesy and copyright of Mike Pollard |
The Upper Cherwell Valley area covered by this blog is just north east of Banbury and the Grimsbury Reservoir up to the old Lock Keepers cottage near Little Bourton. It is crossed by the M40 motorway and the Chiltern Main Line railway and also has the Oxford Canal going through it almost parallel to the River Cherwell.
The habitat is predominantly grazing pasture but has some areas that are not grazed and are becoming rich wet grassland habitats. In 2011, through to 2012, the flood alleviation scheme was constructed and a large borrow pit was dug. This is now filled with water and is referred to as the 'Borrow Pit pool' on this blog. There are plans being developed to turn this area into a country park to maintain and enhance this important flood plain habitat.
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| The Upper Cherwell Valley |
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| The Borrow Pit pool |
