Chalk streams are a rare and important habitat where the flowing water is fed by a chalk aquifer. 85% of the World's chalk streams are found in England, supporting species such as Atlantic salmon, trout, kingfishers, rare invertebrates, and aquatic plants such as water crowfoot. They are an iconic feature of England's landscape, famous for crystal clear water, clean gravels and vibrant mats of vegetation.
Chalk streams are impacted by several pressures such as channel realignment and over-deepening, pollution, and are particularly vulnerable to pressures related to groundwater levels. This was highlighted in WWF's State of England's Chalk Stream Report in 2014 and the Chalk Stream Strategy Report in 2021.
The CaBA Chalk Stream Strategy has made recommendations for improving England's chalk streams which includes thinking of chalk streams in the framework of the “trinity of ecological health” - water quantity, water quality and physical habitat quality, as well as working towards an "overarching level of protection and priority status for chalk streams and their catchments".
