Butterby Oxbow is a Site of Special Scientific Interest

Site of Special Scientific Interest

A Site of Special Scientific Interest is a conservation designation denoting a protected area in the United Kingdom. SSSIs are the basic building block of site-based nature conservation legislation and most other legal nature/geological conservation designations in Great Britain are based upon...

 in the Durham City district of County Durham

County Durham

County Durham is a ceremonial county and unitary district in north east England. The county town is Durham. The largest settlement in the ceremonial county is the town of Darlington...

, England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

. It consists of a former meander of the River Wear

River Wear

The River Wear is located in North East England, rising in the Pennines and flowing eastwards, mostly through County Durham, to the North Sea at Sunderland.-Geology and history:...

 which was isolated from the main river in 1811 when, to reduce flooding in the area, a new channel was constructed across the neck of the meander. It is located about 3 km south of the centre of Durham and 1.2 km north of the nearest village, Croxdale

Croxdale

Croxdale is a village in the civil parish of Croxdale and Hett, about 3 miles south of Durham City, in County Durham in England and on the A167 road, formerly part of the Great North Road.It is the location of Croxdale Hall, a Grade I listed building...

.

The site is notable for the succession series of swamp

Swamp

A swamp is a wetland with some flooding of large areas of land by shallow bodies of water. A swamp generally has a large number of hammocks, or dry-land protrusions, covered by aquatic vegetation, or vegetation that tolerates periodical inundation. The two main types of swamp are "true" or swamp...

, fen

Fen

A fen is a type of wetland fed by mineral-rich surface water or groundwater. Fens are characterised by their water chemistry, which is neutral or alkaline, with relatively high dissolved mineral levels but few other plant nutrients...

 and fen-carr

Carr (topography)

A carr is a type of waterlogged, wooded terrain that, typically, represents a succession stage between the original reedy swamp and the eventual formation of forest in a sub-maritime climate....

 which has developed and which is rarely found as a complete sequence in the county. It is locally important as a roosting and wintering area for wildfowl.