Thames Water Shortlists Three Bidders for £5.7 Billion Main Construction Contract for White Horse Reservoir in the UK

en.Wedoany.com Reported - On October 1, Thames Water officially invited three consortia to bid for the main works contract for White Horse Reservoir in Oxfordshire. The winning bidder will be responsible for the design, construction, testing, and commissioning of the reservoir, with the main works contract valued at approximately £5.7 billion. The project was previously advanced under the name South East Strategic Reservoir Option (SESRO) and was renamed White Horse Reservoir in 2026.

The three shortlisted consortia are: WFH JV, led by Webuild and comprising Hyundai E&C and FCC Construcción; BMV+, led by Bouygues Travaux Publics and comprising J. Murphy & Sons and VolkerFitzpatrick; and BBV, led by Balfour Beatty Civil Engineering and comprising VINCI Construction Grands Projets.

When Thames Water issued the main works tender notice in January, it set the contract scope as the design, construction, testing, and commissioning of the reservoir and related facilities. The procurement uses a competitive flexible procedure, and the contract structure includes a multi-supplier framework agreement as well as a single Call-Off Contract, the latter based on the NEC4 Engineering and Construction Contract and adopting a two-stage early contractor involvement model. Stage one mainly covers design and construction planning, and upon meeting agreed conditions, the project proceeds to the detailed design and construction stage.

White Horse Reservoir is planned to be located southwest of Abingdon in Oxfordshire, with a designed storage capacity of approximately 150 billion liters. Once completed, the project will supply water to the service areas of Thames Water, Affinity Water, and Southern Water, covering approximately 15 million people in southeast England. The construction period is expected to be about 10 years, and after the reservoir is completed, it will take about two more winters to fill. The current target is to have usable water supply capacity by 2040.

The main works procurement timetable shows that the three shortlisted consortia are expected to submit detailed tender documents in spring 2027, and Thames Water plans to determine the main works contractor in autumn 2027. The procurement documents issued in January listed the expected contract commencement date as August 2027, with the overall contract term extending to March 2043.

Project development is led by Thames Water in cooperation with Affinity Water and Southern Water. White Horse Reservoir is planned to be implemented under the UK Specified Infrastructure Project Regulations framework, with the main works contractor procurement conducted separately from the subsequent Infrastructure Provider procurement. The infrastructure provider will subsequently be responsible for project financing and delivery and will be granted a project licence by Ofwat.