Ofwat has launched a consultation seeking views on its proposed decision to specify the White Horse Reservoir as a Specified Infrastructure Project and on its proposal to issue a Preparatory Works Notice to Thames Water in respect of the reservoir.

The consultation has been launched under the Water Industry (Specified Infrastructure Projects) (English Undertakers) Regulations 2013 (SIP Regulations).

The water sector regulator has set out its reasoning on why it considers the White Horse Reservoir project meets the size or complexity and value for money conditions set out in the SIP Regulations and its reasoning for issuing a Preparatory Works Notice in two separate documents.

If Ofwat decides to issue a “Specification Notice” for the White Horse Reservoir project after the consultation, Thames Water would then be required to obtain competitive bids for an independent third party that will finance and deliver the project. Thames Water would be prohibited from carrying out the project itself, with the exception of certain preparatory works.

Ofwat will then consider designating and licensing the successful bidder as a regulated “infrastructure provider”.

“This competitive tendering process should ultimately help ensure better value for money for customers,” Ofwat says.

Interested parties are invited to comment on the regulator’s proposed decision by 5pm on 14 May 2026. Ofwat said it will consider carefully responses to the consultation before making its final decision. A final decision on issuing the notices and specifying the reservoir is expected by August 2026.

Responses can be emailed to This e-mail address is being protected from spambots. You need JavaScript enabled to view it or by post to: Major Projects Team, Ofwat, Centre City Tower, 7 Hill Street, Birmingham, B5 4UA.

Click here to access the consultation documents