£3.6bn Tunnel Proposed to Stop Windermere Sewage — SkimNews
Get the Energy newsletter
Daily energy & climate — solar, EVs, oil, the policy fights and tech bets shaping the transition. Free.
- United Utilities has unveiled a £3.6bn "Only Rainwater into Windermere" (ORiW) proposal to build a tunnel up to 12 miles (19km) long that would stop sewage being discharged into the lake.
- The project would connect 12,800 people to the Windermere sewage network for the first time and include up to 86 miles (138km) of new infrastructure feeding into a single 4m-wide wastewater treatment works.
- Two slightly different plans are on the table — both centred on the tunnel — but one would discharge treated effluent into the River Leven while the other would release it into the Irish Sea at Ulverston.
- The Lake District, a Unesco World Heritage site drawing close to 18m visitors a year, has seen parts of Windermere turn lurid green from algal blooms caused when warm temperatures meet the high nutrient levels in treated effluent.
- Funding options include passing costs to United Utilities customers at up to £3.17 a month or spreading them nationally, adding up to 35p to every English water bill; activist Matt Staniek called the plan a "milestone" but stressed it remained "a plan on a piece of paper."
- The decision now sits with DEFRA, following March 2025 promises by then-Environment Secretary Steve Reed to stop all sewage flowing into the lake; the department said further work is needed to test alternative options.
Why it matters: Windermere's 300bn litres and the Lake District's 18m annual visitors make it a national — even international — symbol of England's water crisis. Whichever route the government takes, bill-payers will shoulder the cost: up to £3.17/month for United Utilities customers, or 35p/month spread across every English bill, to fund a single coordinated sewage system replacing today's fragmented private treatment works and septic tanks.
Ask SkimNews
