United Utilities has defended its environmental record, stating it takes its role in protecting the environment "very seriously", as it announces its revenue has increased by a fifth, while profits rose to £517.8 million for the year ending March 31. But the company has come under fire this week after it emerged it was pumping sewage into a famous body of water that once inspired William Wordsworth.

In a statement, the firm, which has recently boosted its payouts to shareholders, said: "We take our environmental commitments very seriously and are proud to have a sector-leading track record on minimising pollution for over a decade." However, this comes just days after the company was embroiled in controversy over a massive sewage spill.

A new dispute erupted over the condition of England's waters following reports that millions of litres of untreated sewage were discharged into Windermere in the Lake District. Documents from United Utilities, viewed by the BBC, revealed that a malfunction at a pumping station in Bowness-on-Windermere, Cumbria, resulted in illegal sewage discharge into the renowned lake for 10 hours in February.

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Opposition politicians labelled the situation a "scandal", while Downing Street described it as "completely unacceptable". The Environment Agency has the authority to initiate a criminal prosecution if necessary.

The views that captured the hearts of the Romantic poets, overlooking Windermere
The views that captured the hearts of the Romantic poets, overlooking Windermere

On Wednesday, United Utilities explained that the spillage was due to an unforeseen fault on the third-party telecoms cable network in the area, "which United Utilities was not notified about and which affected both the primary system and United Utilities' backup".

The company stated, "engineers took urgent steps to resolve the situation and we informed the Environment Agency within an hour of the pollution being confirmed".

In a statement released with its full-year results on Thursday, United Utilities announced plans to bring forward around £400 million of investment to improve its systems and reduce spills at over 150 storm overflows.

Additionally, the firm is looking to "accelerate environmental schemes in communities such as Windermere, where we are fast-tracking investment to drive improvements earlier".

United Utilities' Chief Executive Louise Beardmore commented: "We take our role in protecting the environment very seriously; our ambitious business plan would see us investing more than ever before to improve services across the five counties of the North West."

She further added, "This would deliver a genuine step-change in infrastructure for the benefit of customers and the environment, and support 30,000 jobs."