What does the pledge mean?

On 21 July 2025, the environment secretary Steve Reed MP pledged that the government would “cut water companies’ sewage pollution in half by the end of the decade”.

The government confirmed this pledge applies to England. Environmental matters, including water management, are devolved in Scotland, Wales and Northern Ireland.

This promise was made in response to the final report of the Independent Water Commission, tasked by the Labour government to review how the water industry is regulated in England and Wales around its “environmental, public health, customer and economic outcomes”.

In a press release published on 19 July, the Department for Environment, Food and Rural Affairs (Defra) said Mr Reed’s pledge referred to a “50% reduction in spills from storm overflows” by the beginning of 2030, when compared to a 2024 baseline.

Storm overflows are outlets from public sewers that act as ‘relief valves’ when there is a risk of the system being overwhelmed during heavy downpours. These storm overflows discharge excess water from the sewerage system into other bodies of water, such as rivers and seas, to prevent rainwater and sewage flooding “back up into homes”.

The Environment Agency monitors storm overflows in England, and issues permits which set out the conditions under which overflows are allowed.

Both the Environment Agency and Ofwat, the existing water regulator, can take regulatory action when those permit conditions are not met—for instance, when overflows occur in dry weather—by issuing fines. In December 2024, Ofwat had already set out a target for water companies in England to have 45% fewer storm overflow spills by 2029 when compared to 2021, with “penalties” for companies failing to meet this target.

A Defra spokesperson confirmed to Full Fact that the government’s pledge referred to the total number of spills recorded, rather than other specific measures, such as the number of hours of spillage. According to Environment Agency data, there were 450,398 monitored spill events in England in 2024, an average of 31.8 spills per storm overflow.

A 50% reduction, then, would see the number of monitored storm overflow spill events in England decrease from 450,398 in 2024 to, at most, 225,199 by the end of 2029 at the latest.

What progress has been made?

We do not yet have data showing the annual number of storm overflow spills since 2024, so we are currently rating this as “wait and see”.

Based on previous releases, we expect data for 2025 to be published in spring 2026.

In July 2025, the government pointed to several policies that it said would help it achieve this pledge, such as increasing Environment Agency funding in 2025/26 and reinvesting water companies’ fines for environmental breaches into “projects to clean up our waters”.