United Utilities Proposes £3.7 Billion Plan to Save Windermere
United Utilities and environmental groups proposed a £3.7 billion infrastructure project to eliminate all sewage and road runoff from Lake Windermere.
A coalition of regulators, local authorities, and environmental groups has unveiled the Only Rainwater into Windermere (ORiW) proposal, a £3.6 billion to £3.7 billion plan to eliminate sewage and highway runoff from England's largest lake. The project centers on a 14km tunnel from Ambleside to transport wastewater to treatment facilities in Ulverston or at the lake's southern end, alongside 86 miles of new infrastructure to connect 12,800 people to the public sewage network.
United Utilities and the coalition argue that existing infrastructure cannot withstand rising temperatures and heavier rainfall, which exacerbate algal blooming caused by raw sewage and nutrient-rich effluent. The plan would expand the local sewerage network by 75%, replacing approximately 1,800 septic tanks and 90 private package plants. If approved, construction could begin in 2030 and take seven years to complete.
Funding options include increasing local United Utilities customer bills by up to £3.17 monthly or spreading the cost nationally across all English bills by approximately 33p to 35p per month if the lake is designated a national asset. While United Utilities has issued an invitation to tender for detailed design work, final approval rests with regulators and the Department for Environment, Food and Rural Affairs, following a March 2025 promise by Environment Secretary Steve Reed to stop all sewage from entering the lake.
