A total of 631 measurements were taken across the Thames catchment area in England and Eindhoven in the Netherlands during the WaterBlitz, which ran from 24 to 27 September. This event brought the total number of global FreshWater Watch samples to over 30,000. Led by Earthwatch Europe, the WaterBlitz has taken place twice a year in the Thames catchment area since 2015, with this year’s expansion into the Netherlands made possible by Earthwatch’s new partnership with Waterchap De Dommel.
The results show a dramatic contrast between the concentrations of nutrients (nitrates and phosphates) in the Thames compared to the River Dommel in Eindhoven. Over half of the water bodies that were tested across the Thames region this autumn showed higher-than-expected nutrient levels. By contrast, only one percent of Eindhoven water bodies were shown to have high concentrations of both nitrates and phosphates. An excess of these nutrients in water bodies is damaging for the environment, and can lead to algal blooms, deoxygenation of the water, and biodiversity loss. Certain types of algal bloom can produce toxins that are harmful to the health of humans, pets and livestock.
Nutrients commonly enter the water as a result of sewage pollution and runoff from agricultural land. Last week, MPs rejected an amendment to the Environment Bill that called for a legal duty to be placed on water companies to reduce raw sewage discharges into rivers.
Dr. Izzy Bishop, Freshwater Research Lead at Earthwatch, said, “We have been running the Thames WaterBlitz for five years now and we see elevated nutrient concentrations across the entire region year-on-year. This is the first time we have also collected data from Eindhoven, and the differences are stark. The water industry in Eindhoven have been working hard to improve water quality across the city and it shows. This makes it even more disappointing for us to hear that MPs have rejected amendments to the Environment Bill that could have helped to clean up our waterways here in the UK.”
The data collected in Eindhoven will be used to ‘fill in the gaps’ in the monitoring system of the local waterboard “Waterschap De Dommel”, to maintain water quality and further improve water quality where needed. Students from the University of Utrecht will do a more extensive data analysis in coming months.
Ineke Barten, Senior Ecologist at Waterschap De Dommel said, “We were curious to see how our effort to improve water quality (remediate soil, improve riverbank conditions, create fish passages) paid off. The big advantage of a WaterBlitz is that volunteers go to many more waterways, including the ones we don’t regularly monitor like the city canals. It provides us with new information.”
Izzy adds, “Thanks to the efforts of hundreds of volunteer citizen scientists, we are collecting more data than ever before about the state of our water. Citizen science has a crucial role to play in environmental research, and is an accessible way for people to connect with nature and show how much they care about their local water environment. It’s vital that the government pay attention to the data they are collecting and act quickly to return our waterways to good health.”
Find out about how FreshWater Watch is being used to gather evidence to make change as part of the Evenlode ‘Smarter Water Catchment’ project.