Test and Itchen Management Catchment

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There are 3 operational catchments in this management catchment.

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    This predominantly rural catchment covers an area of approximately 1,760 square kilometres, and contains two rivers popularly regarded as two of the finest chalk streams in the world with their crystal clear waters supporting a rich diversity of mammal, bird, fish, invertebrate and plant communities. Both rivers are classified as Sites of Special Scientific Interest throughout their courses, with the Itchen additionally designated as a Special Area of Conservation. They are both internationally famous for their trout and salmon fishing, and support local watercress and commercial fish farming, which rely on the high water quality resulting from the groundwater. The geology of the catchment is dominated in the north by chalk, which provides the groundwater upon which both rivers are dependent. The major urban locations in this part of the catchment are Andover, Romsey and Winchester. In contrast, the geology of the southern part of the catchment is dominated by clay, and demonstrates very different stream characteristics. Major urban areas here are concentrated along the coast, such as Southampton, Totton and Eastleigh. The Test & Itchen catchments supply much of Hampshires public water needs, as well as a significant proportion of the Isle of Wights public water requirements. Both rivers have been modified in many ways, and now have many structures and multiple or braided channels along their lengths, supporting mills, navigation and water meadows, which have led to alterations in the flow of these watercourses. Both of these rivers drain into Southampton Water, and in turn, into the Solent.

    This picture of the River Itchen at Winnall, near Winchester in Hampshire, represents a typical picture of a healthy and natural chalkstre