Thames Water has shortlisted three joint ventures for the £5.7bn main construction contract for the proposed White Horse Reservoir near Abingdon, Oxfordshire.
The successful main works contractor will be responsible for designing, building, testing and commissioning the reservoir. Thames Water began the procurement process in January, assessing bidders on experience in areas including tunnelling and large-scale earthworks, as well as financial capacity.
Three consortia invited to tender
- WFH JV: Webuild, Hyundai Engineering & Construction and FCC Construccion
- BMV+: Bouygues Travaux Publics, J. Murphy & Sons and VolkerFitzpatrick
- BBV: Balfour Beatty Civil Engineering and Vinci Construction Grands Projets
Bids are expected in spring 2027, with the contract award anticipated in autumn 2027. The award will be subject to Ofwat oversight, including checks on compliance with the Procurement Act 2023 and value for customers.
Reservoir planned to supply 15 million people
If delivered as planned, White Horse Reservoir would be the UK’s second-largest reservoir and supply about 15 million people across the South East. Its customers would include those served by Thames Water, Affinity Water and Southern Water.
Thames Water estimates that construction will take roughly 10 years once work begins. The reservoir is expected to take two winters to fill, with water available for use from around 2040.
The scheme is one of nine new reservoirs planned in England to improve long-term water security. The South East faces significant seasonal water stress, increasing pressure on infrastructure to store water for periods of high demand and lower rainfall.
Delivery model to follow Tideway approach
Thames Water said the project’s delivery model would mirror that used for the Thames Tideway Tunnel. An independent infrastructure provider is due to be competitively appointed in 2029 to finance and deliver the reservoir alongside the main works contractor.
The construction phase is projected to create more than 1,000 jobs, including positions for geotechnical and civil engineers, ecologists and archaeologists, as well as apprenticeship opportunities.
Simon Adams, programme director for the White Horse Reservoir at Thames Water, said: “The record breaking hot and dry summer has demonstrated just how critical water storage is to the country, so it’s vital we continue to deliver this project at pace.
“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.
“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.”