What is a WaterBlitz?

A WaterBlitz is a FreshWater Watch activity for the whole community. Usually hosted over one weekend, members of the public can sign up to receive a free water testing kit and become citizen scientists by testing a water body local to them. The data collected by hundreds of people over this same time period gives us an accurate and comparable snapshot of water health within a region. Learn more with our WaterBlitz leaflet.

In the UK, events are held across the Thames and Bristol Avon catchment areas. The WaterBlitz also runs in Ireland, France, Luxembourg, Netherlands, Italy and Sweden.

For information about how to organise your own WaterBlitz, contact us.

Past events

Thames WaterBlitz

24-27 September 2021

A fantastic 355 volunteers took part in this event, helping to record 513 measurements. Combined with results from our first ever Eindhoven WaterBlitz, more than 30,000 datasets have now been uploaded worldwide! Your results signal trouble in the Thames, click below to find out more.


Eindhoven WaterBlitz

24-27 september 2021

Hartelijk dank aan iedereen die deel heeft genomen aan ons herst evenement. In totaal hebben 108 vrijwilligers 118 metingen gedaan. Dankzij jullie zijn er wereldwijd nu meer dan 30.000 FreshWater Watch datapunten geupload naar onze database! Wil je meer weten? Klik dan op ‘resultaten’ om het rapport te downloaden.


Making data count

We believe that we cannot truly understand what is going on in our rivers without collecting evidence to demonstrate how healthy, or unhealthy, they really are. We use data collected by you during a WaterBlitz to identify clean waters, to pinpoint pollution hotspots, and to help inform where, who, when and how remedial actions should be taken.

Bristol Avon WaterBlitz

9-12 July 2021

Our friends at the Bristol Avon Rivers Trust (BART) have organised WaterBlitz events since 2016. This year, the team were on hand to give sampling demonstrations on the River Biss and Bristol Frome!


Paris WaterBlitz

4-7 June 2021

The River Seine and many of Paris' other waterbodies have been impacted by urban activities and the loss of green buffer areas. Citizen science data can help to monitor sites across the city. This event was held in partnership with École des Ponts ParisTech.


Pan-European WaterBlitz

7-10 May 2021

Alongside our 11th Thames WaterBlitz, we were joined by citizens from Ireland and Luxembourg. In total, 1,214 volunteers took part, recording 1,568 measurements across all three locations!


Thames WaterBlitz

25-28 September 2020

An amazing 879 volunteers took part in our largest ever Thames Valley event! Click below to read the full WaterBlitz report and view an interactive data map.


Pan-European WaterBlitz

20-23 September 2019

Our first ever Pan-European WaterBlitz saw events held simultaneously in London, Dublin, Paris and Luxembourg. Over 1,100 volunteers took part, uploading nearly 1,000 water quality measurements!


Images: John Hunt, Samuel Oakes, Unsplash/Distillery Images, iStock/Nikada