Last weekend (3-6 May), the Rivers Trust ran its Big River Watch weekend – a simple citizen science activity that helps build a picture of river health across the UK and Ireland.

The app and survey will remain open to collect data year-round. So, if you run a volunteer group or you’re interested in continuing to add information about your local river to the dataset, you can use the app at any time.

Read more and download the app here.

Covered in The Guardian Big River Watch: public to monitor UK and Irish rivers for pollution