‘Wilfully misleading’: EA considering enforcement action after new sewage spill data shows poor performance

The Environment Agency (EA) is considering enforcement action after the latest annual storm overflow data showed the number of sewage spills in 2022 was ‘high and totally unacceptable’, with claims that water companies have reduced the number of spills deemed to be ‘misleading’.

The annual Event Duration Monitoring (EDM) data published today reveals that in 2022, sewage spilled into waterways for 1,754,921 hours.

This is the third year in a row that the ten water and sewerage companies (WaSCs) operating in England have published information on how each storm overflows have operated and for how long they discharged into the environment.


The EDM data shows that there has been a 19% reduction in the number of sewage spills, however, the agency attributes this to a year with lower than average rainfall rather than any actions by water companies.

In a blog post, the agency wrote: “Last year water companies only made improvements to 65 storm overflows – less than 0.5% of the overall total of overflows in the entire system – so we are very confident that water company action has not significantly contributed to the reduction in flows overall.

“For them to claim otherwise is wilfully misleading.”

The EA has raised concerns that incorrect information had been leaked to news outlets such as The Times earlier this week. It noted: “This data did not come from the Environment Agency - it was water companies’ data and is inconsistent with the regulatory EDM data we published today.”

Of the total number of storm overflows listed in 2022, only 91% are equipped with EDM devices, as opposed to the 96% reported by the Times, according to the agency.

There has also been an additional 110 storm overflows listed, which were not reported in 2021 when it became a requirement for all storm overflows operated by WaSC to be reported, regardless of whether an EDM was  installed.

The data shows that the average number of spills per storm overflow in 2022 was 23, compared to 29 in 2021. It also reveals that 3% of storm overflows spilled more than 100 times, compared to 5% in 2021; and 18% of storm overflows did not spill at all, compared to 13% in 2021.

In 2022 sewage spilled into waterways for 1,754,921 hours in total according to the data, which is a 34% reduction on 2021.

The average duration in hours of each spill event per storm overflow was noted to be 5.8 which is the lowest since 2018. In 2017, the average duration in hours was 5.1 which is the lowest since data begins in 2016.

Environment Agency executive director John Leyland said: “We want to see quicker progress from water companies on reducing spills and acting on monitoring data.

“We expect them to be fully across the detail of their networks and to maintain and invest in them to the high standard that the public expects and the regulator demands.”