44% Reduction in Storm Overflow Spills by 2030
Commitment: Water companies must deliver a 44% reduction in storm overflow spill events by 2030 (vs. 2021 baseline).
Owner: Water companies / Ofwat enforcement / Defra policy
Target date: 2030
Metric: Number of storm overflow spill events (reported annually by water companies to Environment Agency).
Status: at-risk
Context
Storm overflow spills are a major source of river and coastal pollution. The 44% reduction is set in the PR24 final determinations, which also require £88bn in upgrades. The £1.6bn accelerated investment (2023) addressed the most urgent sites, including Lake Windermere (United Utilities, £800m, ~8,400 spills/year).
Delivery history
- [April 2023] £1.6bn accelerated investment: £1.1bn specifically for storm overflow reduction
- [December 2024] PR24 Final Determinations: 44% reduction target set; £88bn upgrade programme begins
- [January 2026] Water White Paper: proposes merging Ofwat out of existence. Transition Plan due 2026.
- [2026-04-15] Status: at-risk. Water companies are investing but the regulatory body overseeing enforcement (Ofwat) is proposed for abolition. Transition uncertainty during active investment cycle.
Key dependencies
- Water company capital programmes (£88bn over 2025-2030)
- Ofwat enforcement during transition period
- Transition Plan (due 2026) clarifying regulatory continuity
- Digital monitoring infrastructure (real-time data, part of PR24 requirements)
Tensions
- water-regulator-reform-pr24-uncertainty — Ofwat proposed for abolition during active PR24 enforcement cycle