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Critics Slam Mega-Reservoir Project as a Threat to Ecosystems and Communities

A mega-reservoir being proposed by Thames Water is coming up against criticism and backlash from local residents and environmental groups.

The 150 billion litre reservoir, now named the South East Strategic Reservoir Option (SESRO), will be 25 meters high, and 2 miles across is 50% larger than the proposal Thames Water consulted on earlier this year. It is also 50% larger than the reservoir plans rejected at public enquiry in 2010. This is to be constructed just outside Abingdon, Oxfordshire, on an area of low-lying ground between the villages of East Hanney, Steventon, Didcot and East Marcham. Proposed to start in 2028, and finished by 2037.

With Thames Waters appalling history of managing sewage pollution, with at least 72 billion litres of sewage dumped in the Thames since 2020, (roughly equal to 29,000 Olympic swimming pools.) Their lack of financial stability and mounting debt, there are questions over the suitability of this proposal. This reservoir will boost their balance sheet, and seems it is proposed for the capital and financial benefit to Thames Water.

With this week’s news that Thames Water could run out of money by April, will the Secretary of State see the application as a way of bailing out the company, or a plan that is simply not viable?

We, in this country do not have water security, there is a finite amount of water left on this earth and it is running out fast. Public water resources consist of reservoirs, aquifers and the River Thames. Over the last couple of weeks, we’ve been able to look into our future, with Guildford’s residents being left with no water for well over a week, due to problems with a water treatment works (run by Thames Water).

Many areas will soon be rationed all year round, this shared resource is, in fact not shared equally, with the wealthy using over 50% of the available water, leaving much of the country to use the rest. The effects of climate change, and the social and economic impact of water shortages are very worrying indeed, and something that many aren’t yet aware of. Water is vital for all life and is being controlled in this area by one private company alone.

Un-sustainable abstraction leads to reduced flow in our rivers, and in the case of the Thames’ tributaries, the precious chalk streams that are the arteries of our river’s existence, it is a death sentence. There are just over 200 chalk streams in the world, 90% of which are in our area, and out of those all are in poor health, and many have been declared dead, all due to pollution. This has a hugely damaging effect on our wildlife, river users and biodiversity as a whole.

So, you may think that a mega-reservoir is a great idea, a problem solved – however, you’d be mistaken. The water extracted from the river Thames to fill this gigantic lake will not be used for the residents of Oxfordshire, but for London and the water stressed south-east of England. It will result in destruction of habitats and will not serve local people who gain to lose the most.

Thames Water, Oxfordshire’s only water provider, serving 15 million customers - one in four people in Britain! Leaks over 600 million litres of drinking water per day, the aquifers that feed the Thames are being bled dry after 3 decades of privatisation.

Thames Waters’ largest shareholder is a vast Canadian pension fund, others include China’s sovereign wealth fund and Abu Dhabi’s Infinity Investments. This reservoir will take over a decade to complete, and cost in excess of £1bn, money, which should be spent on fixing existing pipe work, and installing carbon filter cleaning systems on all sewage treatment works.

The company’s to address leakage and deliver sustainable prevention solutions is well publicised, as are the illegal “dry” spills of sewage into the river, including one on the hottest day of 2022! With crumbling, leaking pipes fixed, simple rainwater harvesting, and water management systems installed properly in homes and businesses, and not just deploying the sticking plaster approach taken for the last 30 years, there would totally negate the need for a reservoir.

You may think that there would be benefits for the local area, such as employment, however this is limited as the construction of such a project will require specialist contractors, the majority of whom would have to come from further afield, and even internationally.

The question is, do we want to line the pockets of Thames Water further, when they have a debt pile of over £14bn?

“Oxfordshire County Council has always opposed this destructive development. In an era of rapid climate change, we need to quickly increase resilience to extreme drought, so a reservoir that won't deliver a drop of water until 2040 simply doesn't cut it. The climate-resilient solution to London's water shortage is large-scale water recycling in London as soon aa possible. The rest of the catchment is ill served by delaying the ability to transfer water from the Severn catchment, including recycling from Minworth treatment works and from North Wales, where Vrynwy reservoir already exists. "Are you feeling lucky?" is a very poor foundation for public policy, especially in an era of increasingly violent and unpredictable climatic extremes.” Says Dr Pete Sudbury OCC Deputy Leader with Responsibility for Climate Change / Environment.

Campaign for the Protection of Rural England (CPRE Oxfordshire) for the last 20 years have been challenging Thames Water’s case for this mega-reservoir. “Whilst securing sustainable future for water in our region is critical, and this proposal would seem like a simple solution but will have massive environmental and carbon costs. We need more flexible solutions, offering longer-term resilience, while protecting our countryside and all who live & use it.” Says Richard Harding – Chair, CPRE Oxfordshire.

Derek Stork from GARD – Group Against Reservoir Development says “Thames Water’s decision to ignore all the views of Oxfordshire Stakeholders and ‘double down’ on their Abingdon (SESRO) Reservoir proposal is bad news for all surrounding villages and South Abingdon, but also for Thames Water billpayers. Thames Water’s customers will face a 50-year bill of over £8 billion if the Reservoir goes ahead.

The new proposal brings the reservoir boundary right up to the back gardens of village residents. It puts the Reservoir firmly back on top of present Flood Relief zones and would increase the noise pollution and disruption experienced in the 12-year construction phase. In the event of a Dam Breach accident, the amount of flooding, and the potential loss of life in local villages is also greatly increased.

The essential fact is that this Reservoir, situated in a water-stressed area, brings no new water into the Thames Valley, and is not required if Thames Water just fixed their appalling water leakage record. Every day, they leak more than twice the water which would be supplied by the Reservoir.”

Parties in favour of building of the reservoir say that the reservoir could be used for recreational purposes, like swimming, paddle boarding etc. there is also opinion that it will increase wildlife to the area, which it will, however to the detriment of the Thames, which although in a poorly state currently, will have less water, less flow, meaning when spills take place it will also have a higher concentration of sewage, killing-off any remaining species that call the Thames their home.

Do we want to line the pockets of Thames Water further, when the company has a debt of more than £14 billion?

Laura Reineke

CPRE Oxfordshire & Henley Mermaid


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