Bristol scientists begin £1.6 million river quality research project

By Alice Bullard, 3rd year, Biology

£1.6 million has been awarded to a Bristol-led research project investigating the impact of livestock farming on UK river quality.

The 2021 Troubled Waters report revealed that waterways in the UK are damaged by pollution from sewage, abandoned mines and agricultural waste. Pollution in freshwater depletes quality resulting in a loss of aquatic invertebrates and fish, changes in food chain dynamics and water becoming unsuitable for bathing and drinking. The Natural Environment Research Council and the Department for Environment, Food and Rural Affairs recently awarded £8.4 million to the Understanding changes in quality of UK freshwaters programme to address these issues.

One of the five projects involved in the programme is a £1.6 million Bristol-based research project looking into the effects of agricultural pollution on UK river quality.

The overarching programme aims to investigate how an array of pollutants enter, transform and interact with our freshwater habitats and ecosystems. The Bristol project looks into the effects of agricultural pollution specifically and aims to develop cutting edge approaches to make the UK's waterways more resilient to future climate and land-use change.

Livestock farming is the most popular farming type in the UK, 57 per cent of all agricultural land is home to 9.65 million cattle and 32.7 million sheep. This presents a major source of organic matter pollution to freshwaters.

Professor Penny Johnes of the University of Bristol is leading the project. She said, ‘When livestock excreta are flushed to waters it drives changes in their physical, chemical and ecological quality and function. This material contains inorganic nutrient contaminants typically included in routine water quality monitoring programmes across the UK, but also contains many other compounds which are not monitoring.

These include nutrient-rich organic matter, pathogens, pharmaceuticals and hormones likely to drive significant damage to freshwater ecosystems, and presenting a persistent problem for recreational water use, fisheries and shellfisheries and drinking water abstracted from livestock farming catchments.’

Climate change exacerbates these agricultural pollution pressures on UK freshwater quality due to temperature increase and alterations in flow regime. Additionally, on-farm waste storage capacities can be overwhelmed by increased rainfall resulting from climate change, causing livestock waste to enter nearby water bodies.

Field sites of the programme include Bristol Avon, Conwy and 50 other livestock farming areas around the UK.

The maintenance of UK waterways and the ecosystems they support has social as well as biological benefits. Research shows that exposure to 'blue spaces' such as lakes and rivers can boost our mental and physical health in similar ways to 'green spaces'.

The Understanding changes in quality of UK freshwaters programme runs from 2022 to 2026 and indicates a step in the right direction for our waterways.

Featured image: Unsplash / Isaac Burke