Derwentwater users are being urged to take part in a survey as part of a project to establish water quality.
West Cumbria Rivers Trust and the National Trust need feedback from paddlers, paddleboarders, boaters, rowers and swimmers that regularly use the water at Keswick.
The trusts are working in partnership to carry out water quality testing with the help of volunteers and need the survey feedback for data gathering.
Derwentwater is popular due to its publicly accessible shoreline and the trusts are trying to find out how many people use the water as well as what activities people are taking part in whilst there.
The water quality sampling data will help them find out if the water is fit to swim in and may lead to a bathing water status application.
Users can fill in the short anonymous survey here: https://www.westcumbriariverstrust.org/news/survey