£3.6bn Tunnel Proposed to Clean Up Windermere Sewage

Environmental campaigners and local water company United Utilities have unveiled a £3.6bn proposal to halt sewage discharges into Windermere, the largest lake in England. Parts of the lake have turned a lurid green during summer months due to algal blooming, driven by high nutrient levels from wastewater.

Known as 'Only Rainwater into Windermere' (ORiW), the plan centers on constructing a tunnel up to 12 miles or 19 kilometres long and 4 metres wide to transport sewage away. The infrastructure project will also connect 12,800 people to the wastewater network for the first time through up to 86 miles of new pipes and a single centralized treatment works.

Two distinct options are being considered for discharging treated effluent either into the River Leven or into the Irish Sea at Ulverston. Funding discussions include passing costs directly to United Utilities customers with up to £3.17 added monthly, or spreading the cost nationally across England to increase bills by up to 35p a month given the lake's international significance.

Stock photo for illustration only, not from the actual event

"In the UK we invest in five year periods and so we come along all the time and we do a bit, then we go away and we come back and do a bit more. This is saying we need to do something differently."

Louise Beardmore, Chief Executive of United Utilities

Windermere sits at the heart of the Lake District, a UNESCO World Heritage site attracting close to 18 million visitors annually. The lake holds roughly 300 billion litres of water, requiring nine months for water entering one end to reach the other. Currently, the local wastewater network is fragmented, relying on public works and private septic tanks that overflow during heavy rainfall.