Chalk streams are a characteristic and attractive feature of the Chilterns landscape. They are also a globally rare habitat. In fact there are only 283 chalk streams in the UK, and the UK accounts for around 85% of the global total.

Chalk streams are important habitats for wildlife and support a massive range of species. They are home to some of our most threatened plants and animals, such as the water vole and brown trout. They also have a fascinating history and supported many thriving industries in the past.

Our three films provide an excellent overview, explaining ‘What are chalk streams, and why are they special‘, How chalk streams work, and exploring the threats they face.

The nine Chilterns’ chalk streams are so important that a special partnership project has been created to conserve them. Uniting all the organisations with an interest in the streams, the Chilterns Chalk Streams Project works with local people across the Chilterns to improve river habitats, improve access and enjoyment and promote the sustainable use of water.


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Our 25th Anniversary

We’re pleased to publish the ’25 Years of the Chilterns Chalk Streams Project’ report which summarises project activities, looks at the past and current condition of the Chilterns streams, and sets outs the  future vision for the project.

Recent News

Invasive Species

Freshwater habitats suffer huge impacts from non native plants and animals which have escaped or been introduced into the British...

Smarter Water Catchment Update

An update from the River Chess Smarter Water Catchment project.

Enhancing the Ewelme Brook

With river restoration training days, guided walks and a new advice leaflets for homeowners, there’s plenty going on along the...


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Riverfly Training Day

  • 13th May
  • 9:30am

Learn more about the Riverfly method through the Chilterns

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Circular Walk in the Chess Valley

  • 23rd May
  • 10:00am

Part of the Chilterns Walking Festival, enjoy a 5 mile...

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River Chess Discovery Day

  • 27th May 2023
  • 1:00pm

Come join us for a family fun day launching the...

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Mayfly walk on the River Chess

  • 28th May
  • 2:00pm

Part of the Chilterns Walking Festival, starting at the Red...

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River Chess Smarter Water Catchment

We're key partners in this ground breaking initiative - working on a catchment scale to restore one of the Chilterns’ finest chalk streams to health.
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