Southern Water is inviting interested suppliers to register their interest in participating in a market engagement exercise for biogas assets, digester maintenance and tanks.

The engagement covers establishing a framework for the following general requirements:
- design and specification
- manufacture and/or supply
- installation and commissioning
- planned preventative maintenance (PPM)
- reactive maintenance and repair
- refurbishment and replacement
- process optimisation and performance improvement
Scope covers the following areas -
A. Digester Systems - Southern Water operates 43 digesters across 16 Sludge Treatment Centres (STCs), with a full cleaning and maintenance cycle typically undertaken on a circa 9-year basis. Between major interventions, assets undergo routine inspection and maintenance to ensure continued safe and efficient operation.
B. Biogas Assets - Southern Water operates a range of biogas assets supporting anaerobic digestion and energy recovery processes. These assets are critical to operational performance and safety compliance
C. Tank Systems (Non-Concrete) - Southern Water operates a range of non-concrete tank systems across its water and wastewater operations - circa 200+. These assets are used for a variety of applications including the storage of drinking water, wastewater and sewage treatment, process water, industrial effluent, anaerobic digestion/biogas processes, and bulk solids.
Current estimated start and end contract dates 30 April 2027 to 29 April 2031 with further possible extension options up to to 28 April 2035.
Engagement deadline is 14 August 2026 and estimated publication date of a formal tender notice is currently 17 August 2026.
The engagement process is being conducted via Southern Water's sourcing portal. Suppliers who are not already eregistered on the system will first need to register on the Jaggaer sourcing portal (this is required only once).
Click here to register or log in