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Start Date
01
October, 2012
End Date
31
March, 2015
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9 Chalk Rivers

In 2012 Norfolk Rivers Trust received £1.3 million pounds from the Environment Agency’s Catchment Restoration Fund.  The Trust won this money in partnership with Norfolk Coast AONB, Norfolk County Council, The Wild Trout Trust and local Environment Agency representatives.  The money was for a variety of conservation, education and community projects on the Rivers Mun, Glaven, Stiffkey, Burn, Heacham. Ingol, Hun, Babingley and Gaywood.  Each of the projects aimed to enhance the habitats in and around the river whilst involving local schools and communities.  To find out more about the various projects look at our Rivers, Projects and Community tabs.

Why Chalk Rivers?

The rivers of central Norfolk are made unique by their underlying bedrock: chalk. The permeable chalk acts as a sponge: absorbing rainfall, filtering the water and releasing it though springs and fissures. This means Norfolk’s rivers have a constant supply of clean, mineral rich water, and are not naturally prone to the floods and droughts associated with less permeable bedrocks and steeper river valleys. The chalk which feeds Norfolk’s rivers stretches across eastern England and Normandy, but is not found anywhere else in the world, making our rivers unique.

The constant flow of clear, mineral rich water provides an ideal environment for the growth of aquatic plants, such as water crowfoot, starwort, fool’s watercress and water parsnip. The steady flows also provide continually wet river margins which harbour water mint, hemp agrimony and marsh marigold. Amongst these plants, a huge variety of molluscs and crustaceans thrive, building shells and skeletons from the dissolved calcium. Largest of these is the white clawed crayfish, native to Britain but now seriously endangered by the arrival of the American signal crayfish.

Chalk streams are also noted for their rich insect life, and many species of mayfly, caddis-fly, dragonfly and damselfly spend their early life stages feeding in the richly productive waters. Perhaps the most beautiful of these are the banded demoiselle damselflies which can be seen dancing over the water in mid summer. These jewelled predators feed on many of the less glamorous inhabitants of the river which also emerge from the water in summer, including the many species of fly and midge.

The abundance and diversity of insect life helps sustain the communities of fish that inhabit the river. Most of these species, the trout, eels, lamprey and sticklebacks, probably colonised the rivers from the sea following the ice age, and have since been joined by other fish, including the bullhead and stone-loach. Each of these species has slightly different habitat requirements in terms of fast and slow water, clean gravels or silt beds, each of which are met in a naturally diverse chalk stream.

The rivers are also home to a variety of birds and mammals. The water-vole, which has approached extinction in much of the rest of England, still thrives in Norfolk, probably partly due to the many miles of suitable habitat, but also due to the lesser numbers of American mink. The mink may be kept at bay in Norfolk by the otters, who are now once again present across the county. The aquatic plant-life and marshy river edges also provide excellent feeding areas for moor-hen, teal and the secretive wood-cock and snipe, all reliant on the continuous flow of clean water in and around the river.

Over the centuries the rivers have made way for agriculture and have been straightened and dredged, drained and embanked. Fallen trees, an important source of shelter and food, have been removed and in other places trees have been planted to purposefully drain springs and wetlands. Reversing these processes is difficult, but effective, and can be achieved in places without a loss of agricultural productivity. In other places on the Nar and Babingley, Wensum and Glaven, Stiffkey and Burn, hidden stretches of these magical and unique habitats remain.