In the first phase, a stormwater storage solution will be built by tunnelling 1.8km of pipeline from a pumping station at Moor Pool to wastewater treatment works in Knutsford.
The 2m-diameter tunnel will lie at depths up to 20m. It will store up to 5.5 million litres of stormwater in periods of heavy rainfall, before being treated at Knutsford wastewater treatment works.
The project, which is scheduled for completion in May next year, is part of United Utilities’ £13bn investment over the next five years to protect and improve 500km of waterways.
