A charity has claimed untreated sewage could be responsible for the death of around 200 fish in a Lake District beck.
Cumbria Wildlife Trust said early findings indicated the cause of a pollution incident in Cunsey beck was likely to be the release of untreated sewage directly into the beck.
The following day, around 200 fish were found dead, including trout and pike. Other species of fish found included rare and threatened salmon and eels as well as white-clawed crayfish, an endangered and legally-protected freshwater crustacean.
The beck flows from the Esthwaite Water Site of Special Scientific Interest, near Far Sawrey, into Windermere and connects the two water bodies.
Stephen Trotter, CEO of Cumbria Wildlife Trust said: “We are alarmed and appalled to hear of a recent pollution incident in which a large number of dead fish and crustaceans have been found along a 3km stretch of Cunsey beck.
“Investigations are continuing into the cause of the incident and whilst we await confirmation of the results, the early findings seem to indicate the likely cause is the release of untreated sewage directly into the beck.
“This seems to be a serious environmental and ecological incident, and the beck may take a significant amount of time to recover. It also seems highly likely that a major pulse of pollution could have entered Windermere itself.
“Given the already poor and declining condition of water quality and wildlife in Windermere – due to high levels of nutrient pollution and increasing water temperatures over recent years – any additional nutrients from spills of untreated sewage or other sources are a matter of grave concern.”
South Cumbria Rivers Trust published a report detailing its findings from water samples taken by a member of the public the day after the fish were found dead.
The trust found raised levels of ammonia present in the water.
The Environment Agency is continuing to investigate the incident and Cumbria Wildlife Trust said that depending on the results of the findings, it expects the agency to consider enforcement action.
The agency said it could not release any more information, but the investigation was ongoing.
The charity added that the restoration of the beck and its wildlife to a healthy condition remain an immediate and urgent priority and that relevant players must invest and work together to protect and improve Windermere’s water quality.
United Utilities, which is responsible for Cumbria’s water and wastewater services said: “We have carefully checked all our wastewater systems in the area and we can confirm this incident has not been caused by any of our operations.”
