The Environment Agency has today published water company Event Duration Monitoring (EDM) Annual Return data for 2024 showing the frequency and duration of spills from storm overflows in England - total duration of monitored spill events in 2024 reached a record 3,614,428 hours.
While the data for 2024 shows a 2.9% decrease in the number of sewage spills compared to 2023, ppill durations increased by 0.2% - the EA said that the data shows that storm overflow spill counts and duration remain unacceptably high.
The data also shows that in 2024:
- average number of spills per overflow was 31.8 compared to 33.1 in 2023 and 32.6 in 2020;
- 39% of storm overflows spilled less than 10 times in 2024 compared to 40.5% in 2023 and 40% in 2020;
- 12.5% of storm overflows did not spill at all in 2024 compared to 13.9% in 2023 and 13% in 2020.
In January, the Environment Agency worked with partners to secure the largest commitment of actions and investment from water companies to clean up England's waterways since privatisation. The Water Industry National Environment Programme (WINEP) sets out over 24,000 actions water companies must take over the next five years to meet their legal requirements for the environment, representing a £22.1 billion investment – around £10.2 billion of which will be used to improve storm overflows in England, including nature-based solutions which reduce the amount of rainfall reaching overflows.
To meet the EA requirements, water companies have committed to upgrading over 2,500 storm overflows – which is expected to reduce annual sewage spills by 85,000. Water companies will also install 3,500 monitors at emergency overflows sites, further protecting and enhancing 13,500 km of river.
Chair of Environment Agency Alan Lovell said:
“This year’s data shows we are still a long way off where we need to be to stop unnecessary sewage pollution. But it also provides vital intelligence that drives targeted investment. Using our Event Duration monitoring analysis, we have worked with partners to secure £10.2 billion from water companies to improve storm overflows in England.
“While these improvements get underway, we expect water companies to do what customers pay it to do: ensure their existing assets are maintained and operating properly.
“We will continue to protect our precious water quality and resources by holding water companies to account.”
Environment Secretary Steve Reed: Sewage spill data a “disgrace”
Environment Secretary Steve Reed has described the number of spills from storm overflows as “disgraceful” as the new figures were released.
Steve Reed said:
“These figures are disgraceful and are a stark reminder of how years of underinvestment have led to water companies discharging unacceptable levels of sewage into our rivers, lakes, and seas.
“We’ve already placed water companies under tough special measures through the landmark Water Act, banning unfair bonuses for polluting water bosses and introducing criminal charges for lawbreakers.
“But we will go further and faster. That’s why this government has secured over £100 billion of private sector investment to upgrade our crumbling infrastructure and not only clean up our rivers, lakes and seas for good, but also help deliver economic growth across the country as part of our Plan for Change.”
The government is prioritising water infrastructure upgrades, with £104 billion of private-sector investment secured for the next five years. This will be invested into the water sector and will mean spills are cut by 45% by 2030 from 2021 levels, according to Ofwat.
Water UK says “results are disappointing”
Responding to the publication of storm overflow spill data in England, a Water UK spokesperson said:
“While these results are disappointing, we are starting to see the effect of investment with many companies reducing the number of spills in their area, despite 2024 being one of the wettest years on record.
“From April water companies will invest £12 billion to almost halve spills from storm overflows by 2030. This is part of the largest amount of money ever spent on the natural environment to help support economic growth, build more homes, secure our water supplies and end sewage entering our rivers and seas.”
Click here to access Event Duration Monitoring - Storm Overflows - Annual Returns from 1 January 2020 to 31 December 2024
With the UK government demanding a 50% reduction in storm overflow spills by 2029, the era of reactive management is over. Speaking in the House of Commons on 21 July 2025, then environment secretary Steve Reed said, “This Government will cut water companies’ sewage pollution in half by the end of the decade.”
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