“Chalk Streams First”

                  

“Chalk Streams First” coalition puts forward proposals to cease or reduce abstraction from the Colne and Lea chalk streams

A coalition of conservation and river organisations is working to tackle a major threat to our chalk streams in the Chilterns: excessive groundwater abstraction for our water supply. Chalk streams are amongst the planet’s most rare and threatened freshwater habitats. These streams are fed by groundwater – or aquifers – within the chalk.  Pumping water from the groundwater to supply water for homes and businesses can cause the streams to dry out completely in drought years, threatening the rich diversity of plants and animals these unique habitats support. The chalk hills of the Chilterns give rise to a number of chalk streams, including the River Chess and Ver, and yet per capita water consumption in the Chilterns is amongst of the highest in the UK.

A coalition of conservation and river organisations is working to tackle a major threat to our chalk streams in the Chilterns: groundwater abstraction for our water supply. Chalk streams are amongst the planet’s most rare and threatened habitats and the Chilterns has one of the highest per capita water consumption  in the UK. These streams are fed by groundwater – or aquifers – within the chalk.  Pumping water from the groundwater to supply water for homes and businesses  can cause the streams to dry out completely in drought years, threatening the rich diversity of plants and animals these unique habitats support.

The Chalk Streams First coalition is proposing a regional solution that would replace groundwater abstraction from the Chilterns chalk aquifer with surface water abstraction close to the London storage reservoirs, where water is more plentiful.

Chalk Streams First proposes a reduction in groundwater abstraction that would enable a flow recovery of approximately 80% in the Chiltern chalk streams. The extra flow would then be available to abstract further downstream, near London. A planned pipeline scheme, “Supply 2040”, could move the water from the lower Thames to homes and businesses in the Chilterns formerly supplied by the chalk aquifer.  The chalk streams would effectively become the means of delivering surface water to London’s reservoirs, protecting their delicate ecology whilst ensuring the resilience of public water supply.

Launched in October 2020, Chalk Streams First (CSF) was supported by The Rivers Trust, The Angling Trust, The Wild Trout Trust, WWF UK, Salmon & Trout Conservation and is now joined by the Chilterns Conservation Board, Chilterns Chalk Streams Project, the River Chess Association, the Ver Valley Society and the Chiltern Society.

Historically, groundwater abstraction from the chalk streams around London ballooned in the post-war decades, to the point that in some river catchments in the late 1980s over half the average water available to the river was taken for our water use. In dry years all the water was taken and iconic chalk streams like the Misbourne and Ver dried up completely.

Since then, Environment Agency schemes such as “Alleviation of Low Flows” and “Restoring Sustainable Abstraction” have made some progress in returning some water to the streams’ environment, but the streams still suffer from a very heavy abstraction burden and dry up – for example in 2019. The CSF coalition argues that only a regional and large-scale reduction will re-naturalise flows to these streams to the point where we see good ecological recovery.

So far, CSF has been recognised and conditionally supported by regulators and has been named as a flagship flow-recovery project in the recent national Chalk Stream Restoration Strategy (led by CaBA – Catchment Based Approach). The coalition’s plans have been included in the governments water services regulation authority, Ofwat’s strategic resource investigations, and is being considered in water company plans – specifically Thames Water and Affinity Water’s “Thames to Affinity Transfer (T2AT)”. The scheme has yet to be mentioned in the Water Resources South East Regional Plan, though the group is working towards this aim.

Chilterns Society Chief Officer Tom Beeston says: “we are delighted to be able to work with everyone involved in Chalk Streams First, it a great opportunity for us to be part of reversing the damage we have been doing to chalk streams.”

Chilterns Conservation Board CEO Elaine King says: “We are pleased to be a part of Chalk Streams First – a galvanised approach to tackling one of the most urgent threats to these rare habitats. Tackling abstraction must happen now, to ensure the survival of these streams for future generations.”

CaBA chalk stream restoration group chair Charles Rangeley-Wilson says: “Chalk Streams First is the best chance we’ve had to undo the damage caused to our precious chalk streams by decades of over abstraction. Future generations will judge us harshly if we don’t take it.”

Chilterns Chalk Streams Project leads on the work of both the Chiltern Society and The Chilterns Conservation Board.