If the reservoir is approved it will be an above-ground reservoir which will be contained by walls
(or Bunds) between about 30 metres high with building starting in 2025. It will cover 4 square miles
between the A338 and the A34 north of the railway line - that's the area of 1,600 football pitches.
The surface of the water is likely to be covered with solar panels.
There is unlikely to be any space around the reservoir for leisure facilities.
It would hold between 100 and 150 million cubic metres of water and be capable of providing 600 million litres per day.
To see the draft map of the new reservoir see this page from the Thames Water Reservoir - Technical Report.
For more background
Since 1975, Thames Water has considered options to increase the water available to London residents and the Abingdon Reservoir between Steventon, East Hanney and Drayton has been one of those options.
In 2010 a Public Enquiry ruled that Thames Water had not proven the case for a reservoir of 100 million cubic metres of water to supply the South East.
Thames Water are looking to find an additional 660 million litres of water per day - not for themselves but to provide water to Portsmouth and East Anglia.
They have the worst leakage record of all water companies – they were even fined by OFWAT for missing targets. The plan proposes to reduce leakage by 50% by 2050. However, if their leakage per property was as good as that of Southern Water or Anglian Water they could save about 260 million litres per day rather than the 110 million in the plan.
The plan states that by 2025 Thames Water will install a further 700,000 smart meters in customers’ homes, expecting to save 49 million litres of water per day. How much more could be saved after that from the remainder of the 15 million customers? A very conservative estimate would be at least 200 million litres more per day from a further 10% of customers.
By 2025 Thames Water plan to visit nearly 300,000 customers’ homes and businesses to promote water efficiency. This programme is estimated to save 24 million litres of water every day. Once again how much more could be saved in future years from the remainder of the 15 million customers? We think it would be a minimum of 100 million litres per day from an additional 10% of customers.
Action organisation GARD (Group
Against Reservoir Development) has battled for years against Thames Water's proposals for an
They believe that other options are less costly, less damaging to the environment, less disruptive to local communities and more robust against climate change than the reservoir.
This is a map of where we think the reservoir will be
this can be accessed on a separate tab here).
The Department for Environment, Food and Rural Affairs (DEFRA) reported that on 3 April 2023 the Government released a new "Plan for Water" which covers both the water environment – how clean it is – and water resources – how much of it we have.
For details of the Statutory bodies and organisations responsible for the water system see
DEFRA is responsible for setting the overall water regulatory and policy framework in England.
This includes developing new policies, drafting legislation, and creating special permits, for example, drought orders.
The Environment Agency is the environmental regulator in England. They regulate industries including the water and sewerage and agriculture sectors. They protect and improve the environment by monitoring pressures, investigating sources of water pollution and managing our water resources. They also protect homes and businesses by managing flood risk.
Ofwat is the economic regulator of the water and sewerage sector. Ofwat is responsible for protecting the interests of consumers, promoting water company competition, and ensuring that water companies can properly carry out their functions and finance them as well as meet their legal environmental obligations.
Natural England is the government’s advisor on the natural environment. Their purpose is to protect and improve England’s natural environment and advise on the impacts of actions, for example, the impact of permits on protected sites.
The Forestry Commission increases the value of woodlands to society, which benefits water management and water quality through, for example, tree planting and woodland creation.
The Drinking Water Inspectorate is the drinking water quality regulator. They make sure the drinking water supplied by water companies is safe to drink and meets the legal requirements. They do this by checking the tests that water companies carry out on drinking water and inspecting individual companies.
The Consumer Council for Water represents consumers within the water and sewerage sectors. They investigate consumer complaints that have not been satisfactorily resolved by the water companies.