The river Misbourne should be a pristine, gin-clear chalk stream teeming with invertebrates, fish and birds, but today it is little more than a dirt track. Allen Beechey, who runs the Chilterns Chalk Streams Project, gestures to the muddy path that used to be the river and explains the “chronic problem” affecting the area’s chalk streams. “Abstraction in this area has gone up exponentially since the end of World War Two… abstraction pressure is building massively and very quickly and the situation is getting progressively worse,” he says.
Chalk streams are rare and fragile habitats. There are only around 225 in the world and around 85% of these rise from chalk aquifers in England. Their waters are clear, clean, mineral-rich and because they spring from below ground they are warmer than rain-fed rivers, enabling life to thrive throughout the year.
When healthy and flowing strong, they are home to brown trout, Atlantic salmon, brook lamprey, bullhead, otters, water voles, kingfishers, water shrew and white-clawed crayfish. Plants such as water crowfoot, starworts and watercress thrive here. But drought, population growth, development and abstraction are quite literally sucking them dry.
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