To: The Secretary of State for the Environment

Stop Thames Water’s costly mega-reservoir – fix the leaks!

Stop this from becoming the next water company scandal.
Thames Water leaks over 600 million litres of water per day. Instead of focusing on fixing this they want to build a destructive £2 billion pound mega reservoir, (now estimated to be between £5.5 and £7.5 billion) paid for by us.

Why is this important?

The reservoir could only replace a fraction of the water they lose through leaks and, studies show, it would be unlikely to provide water in droughts.

Why does Thames Water want to do this? A mega reservoir would be an asset on their balance sheet, rather than the ongoing cost of fixing leaks.

By ignoring and not costing major issues such as flooding and safety, Thames Water has grossly under-estimated the cost of the reservoir in their aim to promote it over more sustainable options such as fixing leaks, water transfer and desalination. These solutions would also be more reliable in droughts and much quicker to implement. This would prevent unnecessary continued damage to our chalk streams and hose pipe bans for at least 7 years before the reservoir can possibly be delivered.

Those that have looked in detail at the proposals - including local MPs and Councils of all political persuasions - all conclude that it is a deeply flawed project that is being driven by commercial ambition rather than what is best for a safe and secure future water supply.

Aug 2025 Update: As predicted, the estimated cost has escalated from £2.2billion to between £5.5 to £7.5 billion. This far exceeds the tipping point at which they previously acknowledged the Severn-Thames Transfer (STT) would offer better value yet there has been no revaluation of what is best value for customers.

How it will be delivered

We aim to deliver the petition in person to the Secretary of State, or their representative, at the Defra offices in London.
GARD and CPRE Oxfordshire were successful in challenging Thames Water in a 2010 Public Inquiry. Now we need to take action again. With your help we can win once more, this time for good!

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Updates

2025-12-17 17:27:16 +0000

Final consultation closes 13 January: £7bn mega-reservoir still unproven – your voice matters

Last chance to respond: Thames Water’s largest-ever reservoir faces unresolved risks. Regulators admit Thames Water have failed to prove it is the best value option.

For more information and how to respond to the consutlation please see https://groupagainstreservoirdevelopment.org/2025/11/12/final-consultation-now-open-please-respond/

2025-12-17 17:21:08 +0000

Oxford County Council passes unanimously motion on emergency drawdown
Reservoirs like the proposed reservoir near Abingdon are not just benign boating lakes. A massive above-ground embanked reservoir of this size (six times the volume of any other embanked reservoir) carries unique risks. The lack of serious design effort on proper reservoir engineering and safety by Thames Water, while devoting its efforts to virtual-reality tours of proposed leisure facilities, is simply unacceptable.
For more details please see https://groupagainstreservoirdevelopment.org/2025/12/09/oxford-county-council-debate-reservoir-emergency-drawdown/

2025-07-16 19:02:13 +0100

Andy Cooke, Water Champion for the Vale of the White Horse has published a series of articles which take a deep dive into the controversy surrounding the Abingdon Reservoir proposals. He writes 'Thames Water keep telling people that SESRO is essential, and we have no other options. And people keep printing that with minimal questions and challenge. But, we certainly do have options...'
SESRO is the 'slowest, hardest, least effective, and most expensive option.'
To read more see:
https://oxfordclarion.uk/abingdon-reservoir-is-there-an-alternative/
https://oxfordclarion.uk/abingdon-reservoir-what-are-the-risks/
https://oxfordclarion.uk/abingdon-reservoir-how-much-will-it-cost/

2025-06-25 23:22:39 +0100

We've launched a new website!
https://groupagainstreservoirdevelopment.org
Your toolkit for fast, clear, and expert-backed facts that challenge the spin.

💥 Know someone who thinks all reservoirs must be good? Send them our way

2025-06-25 23:18:34 +0100

This week, the Secretary of State’s refusal to allow public scrutiny thus far into Thames Water's proposed mega-reservoir is being challenged in court by SAFERWaterS and CPRE.

This Judicial Review on the 25th and 26th June is about more than a mega- reservoir. It’s about democratic accountability. It’s about challenging a process that has ignored independent expert warnings and shut out scrutiny.

2025-05-20 19:19:17 +0100

Join GARD for an information session hosted by the Abingdon Carbon cutters Wednesday 28th May 7.30pm. Abingdon Baptist Church, 35 Ock Street.

2025-04-22 23:24:33 +0100

Join us for online information sessions on the 1st, 7th and 8th May 2025. Use the link below or Google Abingdon Reservoir zoom meetings.

https://www.abingdonreservoir.org.uk/2025%20Zoom%20Meetings.html

2025-04-22 23:19:55 +0100

The campaign continues. In spite of DEFRA Secretary Steve Reed’s decision in August 2024 to ‘nod through’ the Thames Water plan (including the huge SESRO Reservoir project at the (un-consulted) size of 150 Billion litres, the Abingdon (SESRO) reservoir still has to go through further approvals – culminating in a Development Consent Order (DCO) hearing in 2027.

In the meantime, GARD’s sister company ‘SAFERWaterS’ and CPRE have launched a claim in the High Court for a Judicial Review into the Government’s decision to proceed with Thames Water’s plans for the Abingdon Reservoir without a Public Inquiry. The High Court Judge has ruled that our claim is 'significant' and a Judical Review hearing has been scheduled for 25th and 26th June 2025.

2025-01-17 13:49:33 +0000

5,000 signatures reached

2024-09-04 10:59:11 +0100

The wildlife and 7sq km of Oxfordshire Countryside Thames Water plan to demolish.

Wildlife photographer Simon Booker explored the area at risk with ecologist Julian Parfitt recording images of what is threatened, naming it 'Diluvium', the Latin for flood.

✖️53 miles of hedgerows and trees,

✖️36 miles of watercourses,

✖️over 200 ancient and veteran trees.

✖️In total 7sq km of farmland and woodland

✖️with irreplaceable loss of habitat for a diverse range of wildlife including rare species of bats and birds.

Thames Water are planning to make the monstrous Abingdon mega reservoir even bigger with even less space for environmental mitigation.

Is this necessaryThere are better, less destructive and more sustainable ways to ensure water security.

Https://youtu.be/6fcnuNwtTaA

2024-03-28 18:20:09 +0000

1,000 signatures reached

2024-03-22 15:15:13 +0000

500 signatures reached

2024-03-19 10:59:39 +0000

100 signatures reached

2024-03-18 22:10:07 +0000

50 signatures reached

2024-03-18 17:48:49 +0000

25 signatures reached