England's Sewage Spills Nearly Cut in Half in 2025 — But Is It Really Progress?

England's Sewage Spills Drop Sharply in 2025 — Weather or Real Reform?

Raw sewage discharges into England's rivers and coastal waters fell by nearly half in 2025, according to the latest figures from the Environment Agency. While the headline number sounds promising, regulators and environmental groups are urging caution — pointing to unusually dry weather as the primary driver behind the dramatic decline.

A Significant Drop in the Numbers

Water companies released untreated sewage for approximately 1.9 million hours throughout 2025, a steep fall from the 3.6 million hours recorded the previous year — representing a 48% reduction. Despite the striking improvement on paper, the Environment Agency was clear that infrastructure upgrades are not the main reason behind it.

The link between rainfall and sewage overflows is well established. When heavy rain falls, combined sewer systems — which carry both stormwater and wastewater in the same pipes — can become overwhelmed. Controlled releases of sewage are then triggered to stop the system backing up into homes. With England experiencing rainfall levels 24% below average in 2025, including one of the driest starts to a year in decades, fewer of these overflow events were triggered.

Industry Claims Credit, Environmentalists Push Back

Despite the Environment Agency's measured stance, the water industry's representative body, Water UK, argued that the figures reflect something more meaningful. The organisation pointed to a tripling of investment by water companies in recent years, highlighting United Utilities' upgrades to more than 400 storm overflows and Yorkshire Water's improvements to around 100 overflows within its network. Across the country, there are close to 15,000 such overflow points in total.

In 2024, industry regulator Ofwat approved a significant increase in water bills across England and Wales to help fund an estimated £104 billion worth of infrastructure improvements over the next five years.

However, environmental campaigners were far less convinced. James Wallace, Chief Executive of the charity River Action, described the lower spill figures as "inevitable" given the dry summer conditions, adding that water companies "are still profiting from pollution" while regulators have failed to intervene effectively. His views were echoed broadly across the environmental sector, with charities arguing the data offers no genuine evidence of systemic improvement.

The Hidden Danger of Dry Spilling

Beyond the overall headline figures, a more troubling issue has come into sharper focus. For the first time, the Environment Agency published data on so-called "dry spills" — instances where sewage is discharged into waterways even when it has not been raining. Unlike overflow events during storms, dry spilling is illegal, and the absence of rainwater to dilute the waste makes it particularly hazardous to both wildlife and human health.

The regulator recorded 14,700 dry spill incidents in 2024, following a series of BBC investigations in 2023 that uncovered the practice was occurring on a significant scale. The Environment Agency confirmed it is now actively investigating these incidents and could pursue enforcement action ranging from formal warnings to unlimited financial penalties. In 2024, water companies collectively paid £6.9 million in fines for environmental law violations.

Why Sewage in Waterways Is a Serious Public Health Concern

The consequences of sewage pollution stretch well beyond unpleasant smells or visual contamination. Excess nutrients from sewage discharge encourage algal blooms, which deplete oxygen levels in the water and can prove fatal to fish and other aquatic life. Sewage also introduces harmful materials — including microplastics and pharmaceutical residues — directly into rivers and seas.

In 2024, a landmark report co-authored by leading scientists, including England's Chief Medical Officer Professor Chris Whitty, warned that sewage-contaminated waterways represent a genuine and growing risk to public health.

A Long Road Ahead

Water minister Emma Hardy acknowledged the improvement in spill figures while stressing that the current situation remains unacceptable. "There is still an unacceptable amount of sewage entering our waterways and a long way to go in cleaning up our rivers, lakes and seas," she said.

The Environment Agency echoed this sentiment, emphasising that "sustained investment" will be essential to achieve meaningful, long-term change. England's ageing combined sewer network — already under strain from population growth and increasingly intense rainfall events driven by climate change — will require far more than a dry year to be brought up to modern standards.