Britons urged to help monitor state of rivers, streams and canals

Autumn Water Watch survey aims to build national picture of pollution, plastic litter and invasive species

The public are being asked to take part in the first national water watch to survey rivers, streams and canals as part of a monitoring project.

The Autumn Water Watch aims to follow the success of the Big Garden Birdwatch and the Big Butterfly Count, in which hundreds of thousands of people record observations to feed into a national picture.