Thames Water launches consultation for reservoir plans

Computer generated image of proposed Abingdon Reservoir from the North of Oxfordshire

A 12-week public consultation has begun on proposals for a new reservoir.

Thames Water wants to build a reservoir near Abingdon, Oxfordshire, which it said would secure the future water supply of 15 million people across the South East.

The reservoir would supply Thames Water, Southern Water and Affinity Water customers.

Campaigners have established, via a Freedom of Information request, that the Environment Agency (EA) provided detailed advice and analysis of the plan, and highlighted that it needed further changes.

The construction of a new large-scale reservoir would ensure enough water for the South East says Thames Water

Proposals for the reservoir, known as SESRO (South East Strategic Reservoir Option), have been developed in conjunction with all three companies.

Thames Water’s head of engagement, land and consents, Leonie Dubois said: “We have a unique opportunity ahead of us to address the water shortage risk.”

“Investing in SESRO would provide a drought insurance policy for households and businesses right across the South East,” she added.

Thames Water predicted it would need an extra 1 billion litres of water every day by 2050 to meet customer demand, expected population growth and effects of climate change.

It said the construction of a new large-scale 40,000,000,000 gallon (150Mm3) reservoir would ensure it would be able to face those challenges.

Thames Water says the reservoir would also provide green spaces for leisure and recreation

A new interim masterplan and design concepts show how the reservoir could look, how it might be built, and how it may benefit visitors.

There will also be community events in Oxfordshire which will include 3D models and virtual reality headsets.

Ms Dubois said that with water resources "under threat", the consequences of not investing in a new reservoir "could be to the detriment of millions of people, the environment, and the economy".

Organisational director at water resources South East, Lee Dance, said it was "critical" to have the right infrastructure.

The reservoir will provide a drought insurance policy for households and businesses

'Misleading impressions'

Campaign to Protect Rural England (CPRE) said it believed the consultation to be "a staggering waste of customers’ money".

“Thames Water’s evidence in favour of the reservoir is as full of holes as some of their pipes," said Prof Richard Harding, chair of CPRE Oxfordshire.

"We believe the EA is quite right to be raising these concerns and hope the Minister will now either rule out the reservoir altogether or move quickly towards a Public Inquiry.”

The advice, issued in December 2023 to Defra Secretary of State Steve Barclay, states that the company "should make further changes as set out in" which would require regulators to review them.

A spokesperson for Group Against Reservoir Development (GARD) called Thames Water's new design "merely a set of misleading artists' impressions".

"GARD has recently commissioned a report on this 'design' by a leading expert on Earth Dams, Professor Chris Binnie, which was very critical of the lack of progress and the sketchiness of the design," the spokesperson added.

"GARD submitted the report to DEFRA. Thames have seen it, but they refuse to meet to discuss GARD's concerns until September."

People are invited to respond to the consultation by 28 August.

A second consultation for communities and stakeholders to have their say on the revised proposals will be carried out in 2025.