Twice a year, we run a Big River Watch, and the next one will take place between 24th and 30th April 2026. Anyone can take part in these week-long citizen science surveys that help to build an important picture of river health across the UK and Ireland.

Our rivers are far from healthy. They’re polluted with sewage, plastic, chemicals and nutrients, and just 15% of river stretches in England are in good overall health.

To restore them, we need more information about how they’re doing. You can help us identify and locate the problems. With the Big River Watch app, you can help us identify the issues, which help us influence policymakers and hold polluters to account.

Image by Neil Howard