United Utilities proposes £3.6bn tunnel to protect Lake Windermere

A coalition known as ‘Only Rainwater into Windermere’ (ORiW) has unveiled a £3.6 billion proposal to prevent sewage discharges into Windermere, England’s largest lake. The plan, supported by United Utilities, local authorities, and environmental campaigners, involves constructing a tunnel up to 12 miles long and four metres wide to transport sewage away from the lake to advanced treatment facilities.

Currently, both raw sewage and treated effluent are discharged into the lake, contributing to seasonal algal blooms. Proponents argue the project is a ‘100 year solution’ that will foster ecological recovery, increase resilience to climate change, and protect a local visitor economy valued at £2.4 billion annually. The Lake District, where Windermere is located, is a Unesco World Heritage site that attracts approximately 18 million visitors each year.

The proposal now awaits government approval to determine if the project can proceed and if the significant cost is acceptable.