New Data Exposes United Utilities’ Relentless Sewage Dumping in Windermere

Well, here we are again. New data obtained by Save Windermere under Environmental Information Regulations, and analysed by Professor Peter Hammond from Windrush Against Sewage Pollution, has confirmed what we already knew—United Utilities is still using England’s largest lake as a dumping ground. 

In 2024 alone, just six sewage overflow sites around Windermere spewed untreated sewage for a staggering 6,327 hours. That’s the equivalent of sewage pouring non-stop for 263 days. And as Windermere sits at the lowest point in the catchment, all that pollution eventually ends up in the lake, accumulating year after year.

This isn’t just a bad year—it’s a pattern. Since 2020, those same six sites have discharged untreated sewage for a jaw-dropping 33,410 hours—or the equivalent of 1,392 full days. For context, there are only 1,827 days between 2020 and 2024. 

This analysis comes weeks before water companies are due to submit their annual returns to the Environment Agency. Save Windermere preemptively requested this data before United Utilities submitted its official figures so that we could begin to understand what United Utilities has been up to in 2024. Unsurprisingly, they didn’t hand the data over willingly. After refusing our initial request, they were forced to release it following intervention from the Information Commissioner. That said, we’ll give them some credit—since dropping their legal appeals, their transparency has improved and they have been surprisingly helpful. 

But transparency doesn’t clean up sewage. Despite this new approach, sewage dumping in Windermere remains unchanged — reflecting a corporate prioritisation of shareholder profits over the long-term environmental protection of England's largest lake. 

Now, we can already hear the usual excuses, so we wanted to address those here and remind you to take United Utilities’ rebuttals with a pinch of salt.

Firstly, “It rained!” — No kidding, this is the Lake District. Rain isn’t an unexpected event; it’s the defining feature of the region. United Utilities should be able to operate without polluting during wet weather.

Secondly, “We’re investing £190 million into Windermere” — Sounds great, right? Except this investment (let’s not forget, secured through years of public pressure from Save Windermere) still isn’t enough to secure Windermere’s long-term future. It's clear we need a long-term infrastructure investment plan to completely eliminate sewage discharges into Windermere, given the lake’s cultural, environmental and economic significance nationally and internationally. Other countries with non-privatised water industries have solved this problem—the futures of Lake Annecy in France and Lake Washington in the US were secured via proper investment to remove inputs. Windermere deserves the same.

Finally, there are other semantics tied to UU’s statements in its upcoming investment plan. For example, they will measure the success of their storm overflow reduction efforts based on the number of spill events rather than the total volume of sewage discharged. A previous BBC investigation with Save Windermere revealed a single illegal spill at Glebe Road Pumping Station dumped between 140 million and 280 million litres of sewage into Windermere. These estimates were only possible due to the pump capacity at Glebe Road being known and corroborated by UU insiders, highlighting the need for greater transparency and accountability. UU has the tools to measure volume—the devices are already installed on the sewage works around Windermere—but when it comes to untreated sewage, they would rather not know.

The next round of investment will deliver some reductions in pollution, but not nearly enough to protect Windermere from the growing pressures of climate change. We’ve seen what happens when water companies opt for short-term mitigation over long-term solutions—sewage still dominates the lake’s nutrient load, driving potentially toxic algal blooms, damaging ecosystems and threatening public health – ultimately failing to secure the future of England’s largest lake.

Windermere isn’t just another lake. It’s a national treasure, and there are a whole host of reasons why this government should go above and beyond for Windermere. Here are just a few:

• It sits at the heart of the Lake District UNESCO World Heritage Site.

• Due to its slow-moving nature, water takes an average of nine months to travel from the north to the south of the lake, requiring an innovative management approach.

• Windermere inspired transformative British cultural figures such as Beatrix Potter and William Wordsworth.

• The lake contributes approximately £750 million annually to the local and national economy as a tourist destination.

• Windermere is home to rare and protected species such as Arctic Charr, Atlantic Salmon, European River Eels, White-Clawed Crayfish, and Brook, Sea and River Lamprey.

• Sewage is both currently and historically the largest contributor of nutrients to the algal blooms which turn Windermere green. These blooms pose a potential health risk to recreational visitors and threaten the ecological integrity of the lake by depleting oxygen concentrations. Climate change is expected to exacerbate these issues, with increased rainfall leading to more sewage discharges and droughts promoting prolific algal growth.

It’s clear what needs to be done, the solutions exist, and other countries have proven that protecting a lake like Windermere is possible. But now it’s down to political will and proper investment. We will not stop until all parties have agreed with this overarching objective and we’ll continue to ramp up the pressure until that happens.