Thames Water has issued a final call to comment on proposed new 150 billion litre reservoir in Oxfordshire - deadline to submit comments to the consultation closes at 11:59pm on 13 January 2026.
Image:artist's impression of proposed reservoir
The nationally significant reservoir would be situated southwest of Abingdon and would secure water supply for 15 million people, including Thames Water, Affinity Water and Southern Water customers.
Since October, 1,261 people have taken part seven in-person and two online events and the company has received almost 900 consultation responses.
Feedback gathered will inform the company’s Development Consent Order application which it will submit to the government later this year.
The project is an essential part of Thames Water’s strategy to meet future water demand, in response to the effects of climate change, a growing population, and the need to reduce the amount of water taken from precious rivers and chalk streams.
The reservoir would provide up to 271 megalitres of water per day during drought, the equivalent to around 3 million baths.
Leonie Dubois, Head of Engagement, Land and Consents at Thames Water, said:
“Last year was the hottest and sunniest on record. It’s therefore essential that we invest in new infrastructure, and our reservoir represents one of the UK’s most critical projects.
“Not only would the reservoir protect the South East’s water supply, but it would also create a space for nature and place for people. It would be somewhere communities can walk, sail and cycle and can enjoy for years to come.
“With one week to go, we want to hear from as many people as possible. Previous consultation feedback has already helped to shape our designs, so I’d encourage everyone to have their say and feedback on our plans.”
The consultation represents a critical step for the project, with responses helping to shape the Development Consent Order application Thames Water will submit to the Secretary of State later this year.
Should consent be granted, water would be available for use from 2040.
The company launched its statutory consultation on Tuesday 28 October 2025 to gather feedback on its reservoir plans, including the project design and opportunities to enhance local spaces.
Comments on the project can be submitted to the consultation in the form of written feedback in one of the following ways:
Fill in the online feedback form at www.thames-sro.co.uk/sesro/statcon2025
Emailing the dedicated consultation response email address at This e-mail address is being protected from spambots. You need JavaScript enabled to view it
Filling in one of the printed feedback forms and posting it free of charge to FREEPOST SESRO CONSULTATION.
All responses must be received in writing by 11.59pm on Tuesday 13 January 2026.
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