Technical partners named for Thames Water reservoir

Thames Water has appointed Arup and Binnies joint venture as its technical partner in the development of the Oxfordshire reservoir.

The South East Strategic Reservoir Option (SERSO) in Abingdon, south of Oxford, is progressing in the planning stage and is on track to submit a development consent order in 2026.

The Arup Binnies joint venture will bring engineering design, environmental assessment, planning, and land access and acquisition expertise to the project.

Both Arup and Binnies have worked with Thames on large strategic schemes including the design and construction of Thames Tideway tunnel. They are also involved with developing plans for the Fens and Lincolnshire reservoirs being developed by Anglian and Cambridge water companies.

At Abingdon, Thames and its partners will work towards submitting a development consent order for SERSO in 2026, with a view to begin construction in 2029 ahead of bringing the reservoir online in 2040.

This application will be based on designs and the feedback from stakeholders and communities regarding the site.

Thames has launched a public consultation, which runs to August on the emerging design options and interim master plan.

It includes the company’s preferred options for connections to transfer water between the reservoir and the River Thames; highway access to and around the reservoir site; drawdown infrastructure for emptying the reservoir in emergencies; the location of rail sidings that could be used to transfer materials to and from the reservoir site during construction; and, the position of associated operational infrastructure, like pumping stations and water treatment works, within the reservoir site.

Mohit Farmah, head of procurement and supply chain at Thames said the partnership will ensure the reservoir proposals are compliant with the Planning Act 2008 and developed to a world-class standard.

“SESRO is a nationally significant infrastructure project that has a crucial role to play in the health and wellbeing of 15 million people, the economy and the environment. I have every confidence this partnership will help us to secure that future,” Farmah said.

The site will supply up to 271 megalitres a day to customers across the south east to ease the one billion litre water deficit predicted in the region as populations rise and the changing climate causes shortages.

There has not been a major reservoir built in the UK in three decades but there will, potentially, now be four beginning construction in the coming years.

Havant Thicket, which Portsmouth Water first obtained planning permission for in 1964 but did not proceed with until water demand grew, is due to come online by 2030.

The Hampshire site will supply neighbouring Southern Water to allow the company to further reduce abstraction from chalk streams in the area.

Anglian is embarking on two schemes to serve the east of England, at Lincolnshire and, with Cambridge Water, in the Fens.

The major resilience projects form part of the work nationally to address looming water shortages by the middle of this century.

Other schemes include transfers to move supplies from areas of surplus to drier parts, as well as exploring water reuse schemes and desalination plants.