Balfour Beatty, Bouygues and Webuild shortlisted for £5.7bn reservoir

Three heavyweight contracting teams have made the final cut in the race to build Thames Water's £5.7bn White Horse Reservoir in Oxfordshire.

The shortlisted consortia bring together some of the world's biggest infrastructure contractors, with Balfour Beatty, Bouygues and Italian group Webuild leading rival joint ventures.

Shortlisted consortia

• WFH JV – Webuild, Hyundai Engineering & Construction and FCC Construcción
• BMV+ – Bouygues Travaux Publics, J Murphy & Sons and VolkerFitzpatrick
• BBV – Balfour Beatty Civil Engineering and Vinci Construction Grands Projets

Thames Water has invited all three teams to submit detailed tenders next spring, with the main works contract due to be awarded in autumn 2027. The deal is one of the biggest single construction contracts currently coming to the UK infrastructure market. It covers design, construction, testing and commissioning of the new reservoir south west of Abingdon.

Major works will include huge earthmoving operations to form the reservoir and embankments alongside tunnelling, pipelines, river structures, roads and associated infrastructure.

The proposed 150bn-litre reservoir would be the second largest in the UK. Thames Water expects construction to take around a decade, followed by two winters to fill. Water is planned to be available from 2040. Construction is expected to support more than 1,000 jobs.

White Horse Reservoir, formerly known as the South East Strategic Reservoir Option, is being developed to strengthen supplies for around 15 million customers across the Thames Water, Affinity Water and Southern Water regions. Early testing and ground preparation works are already under way on the site.

White Horse Reservoir programme director Simon Adams said: "Few projects offer the chance to help secure the country's water future for decades to come, which is why we've selected world-class companies who will bid to build White Horse Reservoir."

He added: "As we move into the next stage of the procurement process, we look forward to seeing bids that match our ambitions for this once in a generation project."

Thames Water plans to use the same regulated infrastructure provider funding model adopted for the Thames Tideway Tunnel. A separate infrastructure provider is due to be competitively selected in 2029 to finance the project and deliver it alongside the winning main works contractor.

With tender submissions due next spring and both a main works contractor and an infrastructure provider still to be appointed, the procurement pipeline for one of the UK's largest water infrastructure projects will remain in motion until the end of the decade.