£3.6bn Tunnel Plan Aims to Stop Sewage Discharge into Lake Windermere

United Utilities and a coalition of regulators, local authorities and clean-water campaigners have unveiled a £3.6bn project named Only Rainwater into Windermere (ORiW) to halt sewage inputs into Windermere, England’s largest lake and a UNESCO World Heritage site. The core of the plan is a 12-mile, 4-metre-wide tunnel that would convey waste to a new centralized treatment facility, eliminating both raw discharges during heavy rain and continuous nutrient-laden effluent that fuels green algal blooms each summer.

Louise Beardmore, United Utilities’ chief executive, called the scheme a “100-year solution,” while activist Matt Staniek praised the proposal but warned that implementation remains uncertain. Two routing options are on the table—discharging treated water into the River Leven or the Irish Sea at Ulverston—and financing could be passed to utility customers or spread across England via a modest national surcharge. The Department for Environment, Food and Rural Affairs will review the options before the government decides whether to proceed.