Raw sewage ‘cover-up’ at Windermere World Heritage Site.

In a Panorama investigation, it was revealed that water companies are able to hide sewage pollution from official figures.

One company, United Utilities, incorrectly downgraded dozens of pollution events, including at a famous lake in north-west England.

All downgrades were signed off by the Environment Agency without any incidents being attended.

The regulator, Ofwat, sets environmental targets for water companies in England. An important benchmark is the number of pollution incidents per 10,000 km of sewer. Usually, these are sewage discharges into rivers or the sea due to equipment failures or blockages.

Fines are imposed if companies exceed a given number of pollution incidents, and rewards are given if they don’t.

In 2022, United Utilities was the best performing company in England, according to the Environment Agency. Only 126 pollution incidents were recorded out of 10,000 km of sewer.

For this good performance, the company will be able to raise £5.1m by increasing bills for its seven million customers.

The Environment Agency’s whistleblowers claim the agency is failing to conduct independent checks and downgrading pollution incidents incorrectly.

An insider told Panorama that United Utilities was “controlling the evidence.”

Whenever pollution incidents are reported to the Environment Agency, it assesses their potential impact and decides whether to respond.

There were 931 reported pollution incidents in north-west England between 2020 and 2022, but only six were attended by the Environment Agency.

‘If they [United Utilities] say we should attend, which is extremely rare, then we will attend,’ said the whistleblower. In other words, they are effectively regulating themselves by saying do not attend. We do not attend if they say do not attend.”