Is Your Water Actually Clean?

The 3.6 million hours of sewage discharge recorded in 2024 demand careful reading. Monitor coverage expanded from 862 overflows in 2016 to 14,182 (100%) in 2024, so much of the headline increase reflects better measurement, not more sewage. The more telling metric — average spills per overflow, which controls for that expansion — peaked at 35 in 2019 and sat at around 32 in 2024. Each overflow still discharges, on average, once every 11 days. These were designed as emergency valves; the data shows they operate routinely. Meanwhile, only 16% of English surface waters meet good ecological status, down from 26% in 2009, and no full reclassification has been done since 2019 despite a legal 2027 deadline.

Bathing water tells a similar story of recent reversal. Sites rated “excellent” peaked at 72% in 2022 but fell to 66% by 2025, while “poor” sites nearly doubled from 3.8% to 7.1% over the past decade. Heavier rainfall from climate change is part of the explanation, but the financial data points to something structural: water companies paid out billions in dividends while infrastructure deteriorated. Ofwat has now approved record investment plans for 2025–2030, but the gap between shareholder returns and capital spending over the past three decades is difficult to overlook.

Leakage reveals how deep the infrastructure deficit runs. The industry loses 2,963 megalitres per day — enough to fill over 1,000 Olympic swimming pools — and every one of the 13 water companies is above its individual Ofwat target. Thames Water is the worst, leaking 665 Ml/d against a target of 540. Total leakage has fallen from 3,238 Ml/d in 2017/18, but not fast enough: the industry target of 2,500 Ml/d by 2025 will be missed by a wide margin. Full monitoring coverage means the scale of the sewage problem is finally visible. Whether the same transparency can drive improvement on leakage and river health remains an open question.