Running Water

Running water is one of Britain’s best-loved natural resources. Rivers and streams act as 'wildlife corridors' allowing animals to travel between one part of the country and another. The three main rivers in County Durham are the Tees, Wear and Derwent, and their combined lengths cover nearly 400 km. Many of the County’s oldest woodlands lie on the steep valley sides of the smaller tributaries of these rivers. In the valley bottoms, the floodplains are often lined with hay meadows and pastures containing many species of wildflower. The riverbanks are often lined with alder, oak and ash.

The fast flowing waters of upland rivers usually contain very few flowering plants, although the rocky beds may be covered with mosses. One moss species in the upper Tees is found nowhere else in England and at only two other sites in Scotland. Further downstream where the waters are calmer, more plant species are found. The mid-Wear is the British stronghold for the stream water-crowfoot.

For a river or stream to be at its most valuable for wildlife, the water must be unpolluted. In the upper Tees and Wear, the water is relatively clean and flows quickly through a rocky channel. This turbulence means that the water contains a lot of oxygen and many invertebrates such as caddis flies and mayflies live here. Stretches of river with high numbers of invertebrates attract high numbers of birds, especially the grey wagtail and dipper. Dippers are small chocolate brown birds with a snow-white breast, and are very characteristic of clean upland rivers. They can often be seen looking for food, 'bobbing' and 'dipping' on the rocks that make up the riverbed

Rivers with clean water often support good populations of fish, which provide food for predatory birds including the grey heron and goosander. Rivers with high fish stocks may also attract otters and water voles. These animals were once widespread throughout the county, but populations have declined dramatically throughout Britain due to water pollution and habitat destruction, and their current status in County Durham is unclear. Hopefully, as water quality increases, these delightful mammals will once again become a characteristic feature of the County’s waterways.

Seven of the UK’s fourteen bat species are found in County Durham, and they are naturally attracted to areas with high populations of insects. The Daubenton’s bat hunts exclusively over water and can often be seen flitting around the riverbank at dusk. Prime bat habitat can be found in the mid-reaches of all three of Durham’s main river systems. Rivers are particularly important to bats because they use linear landscape features to find their way around.

In order to protect rivers and their associated habitats and species to the full, it is important that damaging effects such as pollution, trampling of riverbanks and, in the case of smaller watercourses, culverting and engineering works are kept to a minimum.

Sites in County Durham of conservation interest because of their running water features include:

• River Tees and Juniper Woodland at High Force (Durham County Council & English Nature)
• Durham Riverbanks (Durham City Council)
• River Browney at Malton Nature Reserve (Durham County Council)
• Low Barns Nature Reserve and the River Wear (Durham Wildlife Trust)