Diffuse pollution from agriculture seriously harms wild fish.

This is the process by which excess sediments, nutrients and chemicals from agricultural practice seep into the water.

Agricultural Pollution - Wildfish
Agricultural Pollution - Wildfish
Agricultural Pollution - Wildfish
Agricultural Pollution - Wildfish
Water Pattern - Wildfish

What are the impacts of agricultural pollution on freshwater?

1. Excess phosphorus

Phosphates from fertilisers leach into the water and change plant communities. This can lead to toxic algal blooms and disrupts the food chain for wild fish.

Agriculture contributes 25% of the total phosphorus found in freshwater. 

2. Chemical run-off

A cocktail of chemicals and pesticides (including antibiotics, wormers and other types of medication given to livestock) leach into the water and damage the ecology of river systems. 

36% of the pesticides currently in use have been found in catchment-sensitive farming rivers. These are rivers that flow through land areas where free training and advice have been offered to farmers and landowners to improve water quality.  

3. A build-up of fine sediments 

2.9 million tonnes of soil are lost from fields every year in England and Wales, in a process called ‘surface run-off’. Excess fine sediment from this soil loss clogs up spawning redds where wild fish lay their eggs.

Too much sediment can also destroy aquatic invertebrate populations. 

77% of these fine sediments are derived from agriculture. In 2010, soil degradation in England and Wales cost an estimated £1.2 billion in repair.

Key Stats



The percentage of diffuse pollution caused by poor agricultural practices.



of serious pollution incidents in England are attributed to the farming industry.



The contribution of agriculture towards total phosphorus in fresh water.

Regulation of farming practices

The Environment Agency is responsible for regulating the impact agriculture has on the environment. They are failing fresh water because of: 


Inadequate monitoring

Monitoring by the Environment Agency has reduced dramatically. This means there is no longer a true picture of the state of England’s freshwater environment.


Inadequate resources

Previously, farms could expect to be inspected once every 263 years. Following mounting pressure inspections rates have increased, but still fall short of what is required, with an inspection estimated to be due once every 103 years.

Water Pattern - Wildfish

Farming Rules for Water

In April 2018, the UK Government passed into law the Farming Rules for Water (FRfW).

These are a mandatory baseline of good practices that land managers across England must follow to reduce the risk of water pollution from farming.

The FRfW merely ‘codify into law’ what has been in DEFRA’s (formerly MAFF) good practice guidance since the 1980s. There can be little excuse for farm businesses not being aware of the basic requirements now set out in the FRfW.

Limited enforcement by the Environment Agency means the FRfW, so far, have made little difference to improve the quality of fresh water for wild fish.


To prevent pollution from poor agricultural practices, we need:

Monitoring and enforcement

Regulators need a comprehensive freshwater monitoring programme, supported by an effective enforcement regime.  

New environmental land management policies must be underpinned by strong regulatory baselines.

Funding and investment 

Urgent investment in funding and resources is needed for sufficient monitoring and enforcement to be a reality. 


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