Over 40,000 data sets, one simple approach to water testing... - Earthwatch Europe
Photo collage against blue background showing different individuals and community groups engaging in FreshWater Watch water testing

Over 40,000 data sets, one simple approach to water testing…

This Citizen Science Month, we are thrilled to announce that our FreshWater Watch community groups have collected over 40,000 data sets across the globe. For more than a decade, our citizen scientists have used one tried-and-tested method to detect nutrient pollution and fight for positive change.

Why fresh water matters

Every drop of fresh water is precious. But pollution, climate change and over-exploitation have brought our fresh water systems to crisis point. We want to transform our rivers, lakes, streams, ponds, wetlands and reservoirs into clean, thriving habitats for people and wildlife. Just over a decade ago, we launched our FreshWater Watch programmes, using the power of citizen science to give communities across the globe the tools to monitor water quality, identify problems and fight for improvements.

By 2030, we want to see 100,000 people safeguard 10,000 water bodies across Europe and Africa.

Our FreshWater Watch water testing kit (nitrate chart)

Freshwater citizen science – how we do it

Since 2012, we have been connecting communities with their local freshwater bodies through training them in water quality monitoring. Members of the public interested in taking action with FreshWater Watch can find existing community groups or set up new ones using our online portal. Another opportunity is to take part in one of our annual WaterBlitz events. Usually hosted over one weekend, individuals can sign up to receive a water testing kit and become citizen scientists by testing a waterbody local to them.

As part of a longer-term involvement with FreshWater Watch, we train our citizen scientists to carry out the following activities:

  • Record basic visual observations of their chosen local waterbody, such as the surrounding land use, pollution sources, and algae.
  • Assess the turbidity (i.e., how clear or cloudy the water is), using a special optical test called a Secchi Tube.
  • Measure concentrations of two important macronutrient, nitrates and phosphates, using our simple water chemistry testing kits (Kyoritsu tubes). Phosphate and nitrate levels are measured as a colour change, which correlates to a concentration interval, expressed in parts per million (ppm).

Once the survey results have been uploaded to our global platform, our citizen scientists can see their data mapped in real-time, with automatically generated feedback explaining what their results show. Our data map, which has been built up over many years, creates a lasting legacy and is open access, meaning anyone can use it to track and mobilise change.

Watch the video below to see one of our community groups based in Bristol, The Avon Otters, use our water testing kit:

What makes our approach “waterproof”?

As a science-based organisation, we took great care in selecting our FreshWater Watch methodology. We considered several factors including precision and accuracy, quality assurance, and safety.

  • Precise and accurate: repeat measurements by our citizen scientists and students of the same sample show a near 100% precision. Side-by-side testing of FreshWater Watch and laboratory methods have been performed across the globe, including in the UK Centre for Ecology & Hydrology, University College Dublin, the University of Siena, the University of York (CA) and Tanzania Fisheries Research Institute (TAFIRI). The results show that the accuracy of the FreshWater Watch method is above 80%. By using concentration ranges, they allow for the natural variability of the freshwater sample being tested.
  • Quality assurance: some water testing tools need to be regularly calibrated to ensure the measurements are accurate. The advantage of our FreshWater Watch test tubes is that they do not require calibration (they do expire after one year).
  • Safe to use: our FreshWater Watch testing chemicals remain inside a tube and cannot be touched or accessed. Other tools require citizen scientists to open reagent packets, pour them into a vial and then mix them, which increases the risk to accidentally get in contact with the substances.

Our approach to water testing is simple and safe enough to be taught to the next generation of FreshWater Watch citizen scientists. As part of the Evenlode Catchment Partnership, our team is excited about training the first “freshwater citizen science schools” in the area.

What our citizen scientists say…

Turbidity test - Upper Kafue by Clement Chiimbwe & Enock Mwangilwa

“We monitor the Kafue River in Zambia with pupils and teachers from local schools. We found FreshWater Watch when looking for a simplified water quality monitoring kit. Using the app and kit makes this a fun activity! Our data has been used for a report presented to the Zambian water authority.”

Enock Mwangilwa, National Office Projects’ Officer with the Wildlife and Environmental Conservation Society of Zambia (WECSZ)

“We’ve already been doing some freshwater invertebrate monitoring. The chemical sampling with FreshWater Watch has added another layer. The data will help us build a better picture of the liveliness of the river.”

Rebecca Lewis, Coordinator of Riverfly on the Esk (FreshWater Watch group monitoring the Lothian Esk in Scotland)

“Joining Earthwatch’s FreshWater Watch community has had a massive impact on us. Our river-living community is now an empowered group of citizen scientists.”

James Levelle, founder of The Avon Otters (FreshWater Watch group monitoring the River Avon in Bristol)

Join our FreshWater Watch network

Would you like to become a freshwater citizen scientist and make a difference in your community? You can join an existing FreshWater Watch community group or set up your own.

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