More than 140 people have signed up to become citizen scientists this weekend (18 – 21 September), with hundreds of water-testing kits distributed in Yorkshire as concern grows over the health of the county’s rivers.
A growing community of 144 volunteers has signed up to monitor the health of Yorkshire’s rivers, with over 1,000 water-testing kits distributed across the Aire and Yorkshire Derwent river catchments during the first year of Yorkshire Wildlife Trust’s Rivers to Reef project. The strong level of participation highlights the growing interest of communities in understanding and protecting the waterways that run through their towns, villages and countryside, and now Yorkshire Wildlife Trust is calling on even more people to get involved.
The volunteers are part of Rivers to Reef, a pioneering partnership project working to protect Yorkshire’s rivers, estuaries and coastal waters from pollution, from the source of rivers in the hills and moorlands to the North Sea.
Working with partners at Aire Rivers Trust and the Yorkshire Derwent Catchment Partnership, and supported by Yorkshire Water, Rivers to Reef is expanding citizen science across Yorkshire through standardised water quality monitoring, community litter surveys and support for the Great UK WaterBlitz, a national campaign led by Earthwatch.
The Great UK WaterBlitz brings communities together twice a year to collect water samples, creating a snapshot of river health across the country. In Yorkshire, Rivers to Reef is supporting volunteers to take part across the Aire and Yorkshire Derwent catchments, helping to build a deeper understanding of the health of these important river systems.
During the April 2026 WaterBlitz, 197 water samples were collected by Yorkshire volunteers. The samples were tested for nitrate and phosphate, nutrients that can provide valuable insight into the health of a river and potential sources of pollution.
The results revealed a mixed picture. 60% of samples achieved a good overall nutrient rating, while almost one in four were classified as poor. Volunteers collected 163 samples across the Aire catchment and 34 across the Yorkshire Derwent catchment.
While nitrates and phosphates occur naturally and are essential for healthy ecosystems, excessive levels can indicate pollution from sources including agricultural runoff, wastewater and sewage discharges, misconnections and urban development. High nutrient levels can contribute to excessive algal growth, reducing oxygen levels in the water and harming aquatic wildlife.
Ana Cowie, Marine Projects Manager at Yorkshire Wildlife Trust, said: “The response we’ve seen from communities across Yorkshire has been fantastic. Having 144 people sign up to monitor their local waterways, with hundreds of testing kits distributed, shows just how much interest there is in understanding the health of our rivers, and how willing people are to play a part in protecting them.
“But we need more boots on the ground. The more samples we collect, the better we can understand what is happening across our catchments, identify potential pollution hotspots and build a clearer picture of river health.”
Clare Beasant, River Health Improvement Manager at Yorkshire Water, said: “Healthy rivers and the seas that they feed depend on strong connections between people, organisations and the watercourses that flow through communities.
“Combining local knowledge with scientific monitoring means that we can build a stronger understanding of our catchments, and better target actions that will deliver long-term improvements for river health.”
Yorkshire’s rivers drain almost 20% of England’s landmass into the Humber Estuary, the largest freshwater input into the North Sea and an internationally important site for wildlife. The Humber’s ecological condition has remained classified as “unfavourable” for more than a decade, with habitats including saltmarsh, seagrass meadows and shellfish beds in decline.
Rivers to Reef is working to address these challenges by bringing together science, policy and people power to tackle pollution from source to sea.
The Great UK WaterBlitz will take place again in April 2027, when volunteers across the Aire and Yorkshire Derwent catchments will collect water samples over the same weekend, helping to build a detailed snapshot of river health across Yorkshire.
No previous experience is needed, and volunteers will receive guidance and water-testing kits.
You can register your interest in taking part in April 2027’s Great UK WaterBlitz and read the full report from April 2026’s survey here.