United Utilities to invest more than £230m to improve water quality in the River Douglas at its Skelmersdale and Wigan wastewater treatment works

United Utilities has unveiled plans for major investment at two of its wastewater treatment works in Lancashire.

More than £230m will be spent upgrading its Wigan and Skelmersdale works, located between the villages of Hoscar and Parbold, to improve water quality in the River Douglas.

The North West’s water company is developing the scheme to ensure it can meet the demands of a growing population in the area, while also responding to tighter environmental standards.  Work is expected to begin later this year, with all the improvements due to be delivered by 2030.

At both sites, new technology will be installed to ensure wastewater is treated to higher standards before it is returned to the environment. This will help reduce levels of phosphorus, ammonia and iron that enter the River Douglas in treated wastewater. 

The new treatment processes will increase capacity at both works and, together with the refurbishment of existing storm tanks, will help reduce the number of times storm overflows operate during periods of heavy rainfall.

Wigan wastewater treatment works will see the installation of the UK’s largest Membrane Bioreactor (MBR). The high-performance filtration technology produces cleaner water more consistently and provides the additional capacity needed to support long term growth in the area.

United Utilities has already announced £50m of investment at six sites across Wigan to create additional storage that will help cut storm overflow operations in the area.

Simon Holding, Wastewater Business Lead for United Utilities in Lancashire, said: “This investment is vital for delivering improvements to water quality in the River Douglas.  It will help us to future proof our wastewater services in the area as we see new housing developments and the local population continuing to grow.

“By upgrading our treatment works at Wigan and Skelmersdale with innovative technology, we can treat wastewater to much higher standards and reduce the number of times storm overflows operate – which is something our customers have told us they want to see.”

The scheme forms part of United Utilities’ largest programme of water and wastewater investment for a century across the North West. The company is investing more than £13bn before 2030 to protect and enhance over 500km of rivers, lakes and bathing waters, while safeguarding drinking water supplies for millions of customers.

The works will be delivered through United Utilities’ Enterprise delivery model, bringing together United Utilities and seven design and construction partners as one integrated team.