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Reducing agricultural pressures on freshwater ecosystems

Freshwater ecosystems in the UK face a myriad of pressures, with agricultural activities a leading source of impacts. Defra’s Agricultural Transition Plan proposes a “systems” approach to mitigate environmental pressures. This POSTnote first describes the components of UK freshwater catchments, then summarises opportunities for developing a more integrated approach to addressing the pressures that agricultural practices place on freshwaters.

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Freshwater environments and the benefits that they provide, such as clean and plentiful water, are being impacted by human activity. Agriculture and sewage effluent are the leading causes of English rivers not meeting good ecological status. Agriculture affects more than 60% of these failing rivers, with sewage effluent affecting over half. Agricultural issues include use of high levels of nutrients which are applied to land as fertilisers and manures, as well as eroded soil and pesticides, herbicides and fungicides entering watercourses. However, pollution from multiple agricultural sources is difficult to trace and attribute.  

An excess of nutrients from livestock manure and fertilisers entering watercourses is a major source of pollution. Evidence shows that poor understanding of existing regulation contributes to low compliance with policy interventions and despite the inter-connectedness of freshwater ecosystems, monitoring has focussed on large rivers and lakes, historically ignoring smaller freshwater bodies that drain into or connect them. As part of a systems approach, all components of a catchment need to be included in the evidence base.

Government legislation proposes a move beyond the fragmentary policy of the past to a “systems” approach. This will deliver environmental objectives and mitigate the pressures faced by freshwater ecosystems. The UK has different types of water catchments that contain diverse freshwater habitats and a systems approach will require consideration of the range of these ecosystems, their processes and the benefits they provide as well as mitigating the multiple pressures facing them. Water catchments do not recognise governance boundaries which makes integrated management difficult, but a polycentric governance approach, where information is shared in all directions (neither top-down nor bottom-up) could develop a more inclusive decision-making framework.  

Key points: 

  • Fragmented policy approaches have failed to reverse the impairment of England’s freshwater ecosystems: just 14% of rivers are classified as in a good ecological state.  
  • Livestock and soil management, including manure and fertiliser use, are the leading agricultural activities affecting freshwater ecosystems.  
  • Previous water monitoring has focussed on large water bodies, with significant evidence gaps for headwater streams and smaller freshwater bodies. 
  • Defra are funding habitat restoration on farmland under recently announced initiatives. In appropriate locations this could restore water quality and provide other environmental benefits.   
  • Addressing these pressures will require clear targets, further actions, better communication and knowledge sharing and co-ordinated payments to farmers.  


POSTnotes are based on literature reviews and interviews with a range of stakeholders and are externally peer-reviewed. POST would like to thank interviewees and peer reviewers for kindly giving up their time during the preparation of this briefing, including: 

Dr Fay Couceiro, University of Portsmouth

Professor Penny Johnes, University of Bristol*

Dr Matt Ascot, British Geological Survey

Professor Helen Jarvie, Centre for Ecology and Hydrology*

Professor Steve Ormerod, University of Cardiff*

Professor Nick Voulvoulis, Imperial College London

Bob Harris, University of Sheffield

Professor Ian Holman, Cranfield*

Dr Linda May, Centre for Ecology and Hydrology

Professor Edward Maltby, University of Liverpool

Professor Adie Collins, Rothamsted Research

Professor Sean Comber, Plymouth University*

Dr Flemming Gertz, SEGES, Denmark

Arlin Rickard, The Rivers Trust

Charles Watson, River Action UK

Dave Ashford, Brecon Beacons Mega Catchment

Caroline Drummond, Linking Environment and Farming

David Johnson, Catchment-based Approach and The Rivers Trust*

David Smith, Upstream Thinking, South West Water*

Ian Ludgate, NFU*

Sarah Blanford, Sainsbury’s Supermarkets Ltd.

Rebecca Hesketh, Waitrose & Partners

Benjamin Thomas, Waitrose & Partners

Loraiza Davies, Waitrose & Partners

Phil Smith, Environment Agency*

James Price, Perdiswell Farm

Tom Curtis, 3Keel

Stuart Clarke, National Trust*

 * denotes people and organisations who acted as external reviewers of the briefing.

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