Fears Britain's most famous lake is turning GREEN with 'illness causing bacteria' hotspots

Volunteers testing the water quality of Windermere have found "really concerning" pollution in England's largest and most famous lake.

The analysis, in which 350 "citizen scientists" took samples of water at more than 100 locations around the lake, found "hotspots" of phosphorus, which causes algal blooms, and two types of bacteria that cause illness, reported The Times.

Co-ordinated by the Freshwater Biological Association and the University of Lancaster, the Big Windermere Survey was intended to fill gaps in monitoring by the Environment Agency (EA) to give a clearer picture of the health of the lake at a time when the government has committed to clean it up. The news comes after the Express reported that serious water pollution rocketed 60% last year.

The EA examines water quality at four locations around the lake during the summer months as part of its bathing water assessments. In its last classification all four received "excellent" ratings.

However, the more extensive testing by volunteers revealed a different picture.

Untreated sewage discharged

While Windermere's overall levels of bacteria are low enough to give it a "good" water quality rating, they worsen in the summer. The northeast, northwest and southwest areas recorded levels that would earn them a "poor" or failing rating from the EA.

Bacteria can enter the lake from many sources, including from livestock, leaky septic tanks and untreated sewage. The Save Windermere and Windrush Against Sewage Pollution groups counted a record-breaking 140 days last year when United Utilities discharged untreated sewage into the lake.

Testing the lake between June 2022 and November last year, the volunteers also found that all sampled areas had too much phosphorus to earn a "good" water quality rating. Phosphorus is one of the key nutrients that have caused the lake to turn green with algae in recent summers. In 2023 the EA estimated that sewage was the source of slightly more than half of the lake's phosphorus, while the rest was run-off from surrounding settlements.

Urgent action needed

The Freshwater Biological Association is calling on the EA to increase testing and to investigate the pollution hotspots urgently. It also wants to see further investment in wastewater treatment facilities.

Simon Johnson, its executive director, said: "The evidence is clear. I hope that these results will spur people on into better and faster action to rejuvenate this incredible place. When you see a place you love so much, that is so important; when the water quality of that place is below what I think society expects and demands, then that's really concerning. If we can't get this right on Windermere, where are we going to do it?"

The Department for Environment, Food and Rural Affairs said: "This government shares the nation's fury at unacceptable levels of pollution pumped into this national treasure. We have committed to ending sewage pollution into Windermere entirely, boosted monitoring of sewage spills nationwide and are increasing enforcement to hold polluting companies to account.

"We know that there is a lot of damage to undo, but we are getting on with the work to ensure that the British people will be able to see genuine results."