Phase 3 Water Quality Monitoring Outline (2025)
1. Introduction
Friends of the Dart is a Community-Interest Company (CIC) working to protect the River Dart through science, advocacy, and collaboration. One of our key activities is monitoring the quality of the River’s water to understand pollution levels and guide our campaigning efforts.
In 2025, we entered Phase 3 of our water quality monitoring programme. This phase builds on the work we began in 2024 and continues our commitment to sharing accessible, reliable information with the local community, businesses, and partners. The focus is on detecting faecal pollution, identifying potential sources, and providing data to support a healthier River.
Since launching, Friends of the Dart has helped drive significant change. Our campaigning led to the designation of four Bathing Water Sites along the River Dart, and our data and advocacy efforts placed pressure on South West Water to agree to 16 infrastructure upgrades in the Dart catchment. We are proud to have supported other community groups to begin bacterial monitoring on their own Rivers, and work closely with a range of partners, including the Environment Agency, South Hams District Council, DEFRA, University of Plymouth, University of Exeter, the Bidwell Brook Partnership, the River Dart Catchment Partnership, and local communities and businesses.
2. Aims of Phase 3
Phase 3 aims to:
● Continue monitoring and publishing water quality data to the local community.
● Investigate pollution sources, especially in the Dart’s tributaries, to better understand where bacteria levels are elevated and why.
● Improve public access to water quality data across more locations and times of year than current government monitoring allows.
Key questions we hope to answer through this phase are:
● Where in the Dart catchment are pollution levels highest?
● Do certain tributaries contribute more to bacterial loads in the main River?
● How do rainfall events affect pollution levels across the sites?
● Is there evidence of continuous pollution sources, such as sewage treatment works or agricultural runoff, contributing to water quality issues?
We hope that this data will allow us to build a clearer picture of pollution inputs into the River Dart. We will also be considering the role of land use in the surrounding area—including agricultural activity, land gradient, soil types, and land cover.
3. Monitoring Sites
We are currently monitoring 31 sites across the Dart catchment. These include:
● Community-designated main River sites: Holne Weir, Dartington Beach, and Dartington Pontoon – chosen for their popularity with swimmers and other River users.
● Designated bathing waters: Steamer Quay, Stoke Gabriel, Dittisham, and Warfleet Creek – outside of the Environment Agency monitoring period.
Tributaries and investigative sites: including tributaries affected by sewage treatment works and agriculture.
Figure 1. Locations of current Phase 3 water quality monitoring sites across the Dart catchment.
All sites have been selected to help us understand the concentration of Escherichia coli bacteria in the catchment’s watercourses and track possible sources of contamination. Sites are tested twice per month under both wet and dry conditions where possible, to investigate the impact of rainfall and runoff on E. coli levels.
Our monitoring approach is flexible: sites may change as we collect more data and hone in on specific areas of concern.
To learn more about our testing sites, including coordinates and reason for monitoring, please visit our Phase 3 Site Map.
4. Methods
To monitor bacterial contamination, we test for E. coli, a common faecal indicator that lives in the intestines of warm-blooded animals, including humans, and is shed in faeces. Its presence in water suggests recent contamination by faecal matter, which can carry harmful pathogens that pose risks to health.
● Monthly Petrifilm testing: This is our main method – it’s fast, cost-effective, and provides results within 24 hours. It enables us to quickly publish data and keep our community informed.
● Quarterly laboratory testing: We test samples in an accredited laboratory every three months to validate our use of Petrifilm and ensure our results are robust.
To ensure the validity of this method, we conducted a Petrifilm validation study comparing Petrifilm results with those from accredited laboratory testing. This confirmed that Petrifilm is a reliable indicator of E. coli concentrations.
All testing is conducted according to our Standard Operating Procedures, and our data is compared with hydrology and rainfall data to better understand how weather events affect water quality.
5. What’s Next
Phase 3 is already underway and will continue throughout 2025.
In the coming months, we will:
● Continue collecting and publishing data on E. coli levels across the Dart catchment.
● Focus on identifying pollution hotspots and working with partners to investigate possible causes.
● Launch our River Ambassador Project – an initiative to support individuals and businesses in learning about and caring for the Dart. Ambassadors will help raise awareness, share data, and support conservation through education and engagement.
● Work with local stakeholders and partners, including the Environment Agency and research institutions, to expand our understanding of water quality across the region.
To stay updated on our testing results, find out how you can get involved, or support our work, visit:
👉 www.friendsofthedart.org
👉 @friendsofthedart on social media
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