A huge citizen testing blitz of rivers across Britain this summer has found 75% are in poor ecological health as a result of pollution from water companies and agricultural runoff.

Over the weekend of 7-10 June, more than 2,600 volunteers for Earthwatch Europe measured the water quality of their local rivers, providing a snapshot of the health of the country’s rivers. 

During the Great UK WaterBlitz, the citizen scientists measured the levels of two polluting nutrients: nitrates and phosphates, which are commonly present in treated and untreated sewage, as well as in fertilizers that wash off farmland. 

They collected more than 1,300 datasets. 75% of data points across the UK showed poor ecological health with significant regional variation. 

Rivers in the south-east and East Anglia regions of England, including the Thames basin, were among those in the worst state, with 89% of rivers failing to meet tests for good ecological health. “The picture around London and the Thames river basin is particularly dire,” said Dr Sasha Woods, director of science and policy at Earthwatch Europe.

Hertfordshire and Cambridgeshire had the worst water quality, with 91% and 89% of rivers respectively showing unacceptable levels of nutrient pollution. Northumberland and Gwent in the North West had the least nutrient pollution, with the findings suggesting both counties had 100% acceptable water quality.

Woods said the report would not have been possible without the support of people across the UK. “As a nation, we clearly care deeply about the health of our rivers,” she said. “This event has enabled people to better understand the health of their local rivers and catalyzed grassroots action.”

Since 2012, the organization has been connecting communities with their local freshwater bodies by training them in water quality monitoring. Using a simple water testing kit and accessing an online database, the citizen scientists can assess and document levels of nutrient pollution (phosphates and nitrates) over time.

“We want to see more citizen science testing and better use of this data by bodies such as the Environment Agency to help build a more positive future for our rivers,” Woods said.

Under the water framework directive, which is part of British law, all rivers are supposed to attain “good” ecological status by 2027. In 2019, the last time full water assessments took place, just 14% of rivers were in good ecological health.

Woods said the results made it imperative for the incoming government to commit to a national strategy for freshwater that includes all forms of pollution and is backed by a properly resourced organization that makes use of rich citizen science data.

Cover image: Ian Turnell/Pexels