Discover more about our Bioresources business

After your waste goes down the loo, it’ll end up at one of our 569 wastewater treatment works (WwTWs). A key part of our wastewater service is to treat sludge!

Our wastewater treatment captures sludge which is then transported to our Bioresources treatment facilities. Each year these Bioresources facilities treat around 200,000 dry tonnes of sewage sludge. Our main treatment process uses digestion technologies to safely and compliantly treat the sewage sludge. The digestion treatment produces biogas which we use to generate renewable energy and biosolids for onward use.

Waste not want not!

The treated material, called Biosolids is provided to local farmers which can be used as a high quality fertilizer.

We’re accredited

We’ve been awarded accreditation from the Biosolids Assurance Scheme. This certifies that our treatment and recycling activities meet regulatory requirements and best practice. We are audited every year by an independent Certification Body to ensure that we conform to the scheme standards.

Biosolids Assurance Scheme website (BAS)

Looking to the future

Ofwat is changing its regulatory approach for bioresources to promote market development and innovation. We’re working with a range of organisations involved in bioresources services to optimise transport, treatment, recycling and disposal to deliver benefits for our customers and environment.

Bioresources RCV allocation

As part of the revised regulatory approach, bioresources will be treated as a separate price control in the PR19 process. To support this process and to help to ensure that this is achieved in a way which will provide a level playing field for bioresources trading and processing, Ofwat asked water and sewerage companies (WASCs) to submit their proposed allocation of the wastewater RCV to bioresources. The overview of UUW’s submission is available on the “looking to the future” section of our website.

To find information about our bioresources bid assessment framework, click here.


At United Utilities we recycle over 360,000 tonnes of Biosolids each year, applying it as an effective fertiliser and soil conditioner to over 18,000 hectares of land, and across over 1000 farms each year. Click here to find out more about biosolids.

Bioresources market information

To enable potential market participants to identify opportunities to supply services in the treatment, transport, recycling and disposal of bioresources, we are providing information of our bioresources activities in our sewage sludge production sites known as wastewater treatment works (WwTWs) and bioresources treatment facilities (BTCs). The information for 2022/23 can be downloaded here. 

Download report