The water company intends to establish a single-lot, multi-supplier framework agreement to deliver inspection, repair, refurbishment and upgrade works to anaerobic digester assets and associated infrastructure across its operational estate. No supplier is guaranteed any minimum volume or value of work under the framework.

The framework will support the ongoing maintenance, regulatory compliance and enhancement of Thames Water's digester portfolio, which forms a critical part of sludge treatment operations. Works will be required across multiple sites and will be delivered as discrete packages or programmes of work called off over the duration of the framework.

Scope of services to be delivered under the framework includes:

The water company says the nature, scope and value of individual call-off contracts will vary and in many cases, the full extent of refurbishment and upgrade works will only be confirmed following completion of initial decommissioning, cleaning, and detailed inspection activities.

Works packages may therefore comprise a combination of defined and developing scopes, with suppliers required to work collaboratively with Thames Water to refine and deliver solutions based on inspection findings.

The framework is expected to operate across multiple sites within the Thames Water region. Works will need to be carefully planned and executed to ensure continued operational performance of the wider network, including constraints on the number of digesters that can be taken offline at any one time.

Suppliers appointed to the framework will be expected to demonstrate capability in delivering complex, safety-critical works within live operational environments, and to work collaboratively with Thames Water to achieve programme objectives, regulatory compliance and value for money.

Further detail regarding the scope, technical requirements and contractual arrangements will be set out in the procurement documentation issued at the Invitation to Negotiate (ITN) stage.

Current estimated start and end contract dates are 1 February 2027 to 1 February 2031 with further possible extension options up to 1 February 2035.

Call-off contracts will be awarded either:

For each call-off, Thames Water will issue a call-off tender pack ( tenderers will be required to submit both a technical and commercial proposal) setting out:

At the framework award stage (ITN), tenderers will be required to submit a Framework Schedule of Rates, setting out their proposed:

Deadline for submission of enquiries about the tender is 5:00pm on 25 June 2026, and deadline for requests to participate is 12:00pm on 9 July 2026.

Thames Water is asking suppliers who are interested in participating to register by completing an online form - click here to access the form