The River Stour

The Stour rises on the Greensand at St Peters Pump in Stourhead Gardens and flows 96km to the sea at Christchurch; the fall over its entire course is approximately 230m. The catchment lies predominantly within the county of Dorset, with smaller areas in Somerset and Wiltshire. It covers a land area of 1,300km² with a population of about 394,000.

The Stour catchment covers parts of many local planning authorities. The upper reaches lie within Salisbury, South Somerset, West Dorset and North Dorset District Councils, and the lower reaches include East Dorset and Purbeck District Councils and Poole, Boumemouth and Christchurch Borough Councils.

In 1995, 33% of the river length in the Stour catchment was of good or very good chemical quality, 56% was fairly good while 11% was either fair or poor. In biological terms 83.3% of the river was of good or very good quality while the remaining 17% was fairly good. Between 1990 and 1995 there was an overall improvement in chemical quality over 12% of river length while biological quality improved in 17% of the river. Although water quality has recently improved there are parts of the catchment where it is not good enough. These shortfalls in quality are described in the Consultation Report.

Above Sturminster Newton, the catchment comprises a dense network of tributaries which drain predominantly clay soils. This is a domestic farmed landscape of pastures, scattered villages, hedgerows and small woodlands forming an irregular patchwork. The nature of the geology makes it particularly responsive to rainfall.

Below Sturminster Newton, the Stour flows towards Blandford Forum through a narrower valley with chalk hills on either side. The land use is mainly arable on the gentle slopes towards the edge of the floodplain and pasture on the flat valley floor. Settlements and roads either hug the foot of the chalk escarpment or are concentrated on the valley floor, and there are fewer tributaries.

At Wimborne Minster, the Stour crosses onto the tertiary sand and gravel deposits and flows towards Bournemouth across a landscape of typically large open fields, predominantly pasture with arable and settlements along the outer margins of the valley floor.

The Allen flows over chalk for almost all of its length until it joins the Stour at Wimborne. Its valley landscape is much more intimate than the surrounding countryside, with former watermeadows on either side of the river contrasting with adjacent arable fields. Copses and riverside trees are frequent; development is rare, though historic bridges are a feature.

The Crane rises on the chalk, but is known as the Moors River after it enters the tertiary deposits; it is joined by the Uddens Water at Ferndown, and joins the Stour at Hum. It flows through a landscape of low rolling hills with an irregular and enclosed patchwork of pasture, woodland including coniferous plantations, hedgerows and heathland on acid soils.

In Bournemouth, the watercourses are an important part of the townscape, as narrow, wooded corridors. The coastal fringe is heavily populated with the main centres of Boumemouth, Poole and Christchurch. This coastal area, with its bathing beaches and potential for recreational activities, is popular with tourists during the summer season.

Towards the coast, the floodplain widens to form extensive level pastures, marsh and mudflats, meeting the Hampshire Avon to form Christchurch Harbour. This consists mainly of intertidal fine muddy sand with small areas of salt marsh that have a particularly rich flora, and it is very popular for recreation.