£600m design race looms for £3.7bn Windermere clean-up

United Utilities is preparing to launch a £600m design and integration race for its proposed £3.7bn overhaul of wastewater infrastructure around Windermere.

The appointment will help shape one of the water sector’s biggest emerging construction programmes, including major tunnelling, new sewers, pumping infrastructure and advanced treatment works.

A formal tender notice is expected in early November following preliminary market engagement.

The initial design and pre-delivery phase is expected to be worth around £60m to £100m, with longer-term integration and delivery support potentially taking the total appointment to £600m.

United Utilities has narrowed more than 70 options down to two preferred solutions for its Only Rainwater into Windermere programme.

Both involve intercepting wastewater currently entering the lake catchment and transferring it through new underground pipelines for advanced treatment.

The wider proposals include extensive tunnelling, up to 138km of new sewer network, around 35km of highway runoff interception and 37 hectares of sustainable drainage.

Thousands of homes, holiday properties and other premises currently relying on private treatment systems could also be connected to the public sewer network.

Consultants Jacobs and Mott MacDonald have carried out the feasibility work for these preferred options.

United Utilities believes the full programme would cost up to £3.7bn and take around seven years to build once detailed design, planning, environmental and regulatory approvals are secured.

Tunnelling is expected to play a major role in limiting disruption across the sensitive Lake District landscape.

United Utilities chief executive Louise Beardmore said: “After assessing more than 70 options, two have been selected to progress into detailed design, with the potential to deliver lasting environmental, social and economic benefits across the catchment.”

The alternative would be to spend around £2.5bn over coming decades upgrading existing infrastructure while still allowing treated wastewater to discharge into the lake.

£600m design race looms for £3.7bn Windermere clean-up | Construction Enquirer News