A £3.7bn scheme involving tunnelling has been proposed to stop sewage being discharged into Lake Windermere.
A coalition of national and local organisations has today published a landmark feasibility report setting out how England’s largest natural lake could be protected for the next 100 years.
The Only Rainwater into Windermere feasibility study assessed more than 70 potential solutions before choosing two preferred options, both including a tunnel up to 19km long to transfer wastewater to a treatment facility.
The two options would intercept and transfer wastewater from the lake for treatment, with up to 138km of new sewerage network, 35km of highway run-off interception, and 37ha of sustainable drainage. In total, wastewater infrastructure could increase by up to 75% across the catchment, and around 12,800 people could be connected to public sewers for the first time.
The feasibility study estimates the preferred solutions would require investment of between £3.6-3.7bn and generate around £7.5bn in economic, environmental, and social benefits for the Lake District UNESCO World Heritage Site.
Construction is expected to take seven years.
The coalition, comprising the Environment Agency, Lake District National Park Authority, Love Windermere, Save Windermere, United Utilities and Westmorland and Furness Council, is now calling for continued collaboration between government, regulators, delivery partners, and local stakeholders to progress the proposals.
Edward Twiddy, independent convener of the Coalition, said the existing network had one of the highest levels of combined sewers in England, with wastewater sharing the same pipes as surface run-off in a catchment that received 2.5m of rainfall a year.
“Rather than spending £2.5bn on incremental interventions that may never fully achieve these outcomes, and that would bring decades of disruption to communities and businesses, this report presents a £3.7bn investment capable of delivering £7.5bn of benefits,” he said.
“This is ambitious. It is different. But Windermere is unique, and if we are serious about protecting it for generations to come, we need to be prepared to think bigger and act bolder.”
