Testing by citizen scientists of a beck that feeds into Lake Windermere has revealed a huge loss in invertebrate life that campaigners say is being caused by sewage discharges.
Save Windermere and WildFish carried out testing for invertebrates in Cunsey Beck, a site of special scientific interest (SSSI), in order to assess the impact on its freshwater ecology of the Near Sawrey wastewater treatment works, owned and operated by United Utilities.
Their first year results showed a decline of 76% in riverfly species and a 33% reduction in riverfly diversity in samples taken below the sewage outlet compared with samples taken above it.
They said the permit issued by the Environment Agency – outlining when raw sewage can be discharged legally from the treatment works and providing limits for toxic pollutants – is not fit for purpose.