The Times: Insects declined by almost two thirds downstream of a sewage works
“Falling numbers of invertebrates in a key river feeding into Windermere are a fresh reminder of the damage being done to England’s largest lake.
Insects and other invertebrates declined by almost two thirds downstream of a sewage treatment works on a key river feeding into Windermere, water tests have found.
The fresh evidence of harm to rivers replenishing England’s largest lake comes in the same month a 95-year-old science group resigned from a partnership with the local water company, in protest over the pace at which it is being cleaned up.
In recent years the Unesco world heritage site has suffered a series of toxic algae blooms linked to nutrient pollution from sewage treatment works, farming and other pressures.
New water sampling last spring and autumn found that the number of invertebrates in the Rothay, one of the biggest rivers in the lake’s catchment, declined by an average of 64 per cent in waters below a storm overflow pipe at Ambleside sewage treatment works.
The charity WildFish, which took the water samples, identified species such as beetles, leeches and mayflies under a microscope. Invertebrates matter because their numbers and diversity are considered a key indicator of river health.
Tests were also carried out at two smaller rivers. In the Cunsey Beck, there was a 76 per cent reduction downstream of Near Sawrey sewage works, while in the Wilfin Beck the decline was 75 per cent below Far Sawrey sewage works.”
