Sewage alerts across UK mapped after ‘millions’ of litres dumped into Lake Windermere beauty spot

After a report found that “millions” of litres of untreated sewage was illegally discharged into Lake Windermere, campaigners have raised concerns about the levels of pollution in British waters.

Raw sewage was pumped into the Unesco world heritage site for nearly 10 hours in February after a telecommunication failure at a pumping station operated by United Utilities, a major water and wastewater services provider in the North West.

The discharge happened at the company’s pumping station at Bowness-on-Windermere in Cumbria on the night of 28 February and intermittently the following day.

The emergency pumps discharged more than 10 million litres of raw sewage into the lake after the main pumps abruptly stopped due to a telecoms fault, insiders at the firm told BBC News, whose report also cited internal documents from the company.

The latest incident comes amid warnings from environmental agencies that swimming and other activities in and around some of the country’s rivers and lakes could be hazardous due to high levels of sewage pollution.

There were 68,481 incidents of sewage released into England’s seas last year, totalling 440,446 hours, campaign group Friends of the Earth said on Wednesday after analysing Environment Agency data.

Surfers Against Sewage monitors water quality at more than 450 river and coastal locations. The map below shows the most recent update for alerts on Saturday 18 May, and you can see an interactive version on its website.

On Saturday, the map showed approximately 60 red crosses, which represent sewage pollution alerts.

The latest spills come as campaigners gathered across the UK on Saturday to protest against the state of the nation’s waterways.

Activists gathered at over 30 spots across the UK including London and Brighton, where people were seen paddleboarding out into the sea.

Some were seen holding signs and placards calling for clean oceans while others wore costumes to draw attention to the event.

According to the regulator Ofwat, sewage spills come from storm overflows (relief valves designed to release water when the system is at risk of being overwhelmed); for example, if there are sewer blockages or equipment failures at wastewater treatment works. The network then discharges a mixture of rainwater, groundwater and sewage.

The incident at Windermere was not reported to the Environment Agency until around 13 hours later. Failure to promptly notify the agency about such an incident constitutes a criminal offence.

In a statement to The Independent, the Environment Agency said an officer “attended the scene to confirm with UU [United Utilities] that the discharge had ceased and to carry out water sampling in areas affected”.

It added: “We are undertaking a thorough investigation into the incident which involves examining further evidence from United Utilities.

“If we determine a permit breach has taken place, we will not hesitate to take enforcement action. If any water company is found to be in breach of an environmental permit, the Environment Agency will take the appropriate enforcement action up to and including a criminal prosecution.”