The Express: Campaigners question progress to clean England's Largest lake from pollution
A campaigner has accused a water firm and green regulator of “painting a fictitious picture” of Lake Windermere’s pollution. United Utilities (UU) previously claimed a 50% reduction in phosphorus discharges into England’s largest lake, in Cumbria, following investment between 2015 and 2020.
But Save Windermere founder Matt Staniek alleged this figure is based on “unverified assumptions rather than concrete data”. The Environment Agency (EA), in a blog post last year, said that phosphorus levels have declined by approximately 30% since 2020 – contradicting the claims made by the water company.
UU said the EA's 50% figure was the reduction in inputs by the firm following investment over five years. It added that the EA’s 30% figure was based on a model that looks at all inputs into the lake.
High concentrations of phosphorus in rivers can lead to algal blooms, which deplete oxygen levels and harm aquatic life. Mr Staniek said: “When claims are made about environmental progress, the public deserves proof as it's their money being spent on this.
“What’s clear is that both the EA and UU are trying to paint a better picture of what is happening in Windermere than what we see on the ground.
“Until sewage discharges are stopped entirely, Windermere remains explored for greed and profit.”
Save Windermere submitted an Environmental Information Regulation (EIR) request to UU asking for the raw data and modelling documentation underpinning the company’s statement on phosphorus levels.
But the campaign group said the data received, following “an extended delay exceeding the legal timeframe”, was “incomplete, outdated and heavily reliant on questionable modelling rather than real-world measurement”.
Campaigners added: “United Utilities’ justification for the 50% reduction rests on figures comparing pre and post investment phosphorus levels but with a glaring omission: no post-investment monitoring data exists to validate the results.”
Mr Staniek said that as an example, at the Glebe Road pumping station, phosphorus levels were not directly measured.
Instead, data gaps were filled with modelled estimates based on the assumption that higher flow rates would result in lower concentrations.
He said this practice may be suitable for internal estimates but “fails to meet scientific standards for environmental accountability”.
The same datasets are said to form part of the EA’s tools used to guide investment and regulatory decisions in the catchment area.
UU and the EA stood by their respective figures. Thw water firm insisted the two figures were not comparing like for like. Meanwhile the latter said the reductions have been calculated using a model but it is calibrated using real flow and water quality data.
A UU spokesman said: “We’re committed to playing our part in continuing to improve the water quality in Windermere. It’s why we’re on with delivering £200m of investment to ensure we treat wastewater to even higher standards alongside significantly reducing discharges from the six storm overflows that discharge into the Lake.
“This builds on our previous investment of £75m that means our Windermere wastewater treatment works is already treating phosphorous to the lowest achievable limits and has helped to cut the amount of phosphorus entering the lake from our operations by more than half.”
