Sandford Hydro is a community energy project developed by Low Carbon Hub. It is the largest community-owned hydro on the Thames and was commissioned in August 2017.

Check this page for blow-by-blow project updates, or sign up to the Low Carbon newsletter for e-updates. 

Sandford Hydro

The Sandford Hydro in late Autumn 2017. View the full Sandford Hydro Case Study here


Our Running In Phase

11 April 2018

As you might expect with a hydroelectric plant of this size, there is a lot to learn about the optimal running conditions of the Sandford Hydro. We’ve recently been experiencing high water flow (as you have probably noticed!) and even though you might think this is ideal weather for the screws to turn, the amount of electricity generated depends on how far the water drops (the difference in level between upstream and downstream). As the river swells the difference in level becomes smaller and smaller and the amount energy available to be captured decreases. This has all been anticipated. As the water level in the weir pool (downstream from the hydro) is currently very high, we have decided to stop the hydro to prevent any potential damage to the plant and will be putting them back on as soon as we judge to be prudent.

However, to give you an indication of the power of the largest community-owned hydro on the Thames, here are some stats since 20 February 2018:

•    Days operational: 29
•    Electricity produced: 210,317.70 kWh
•    CO2 savings: 94.50 tCO2

For more information on the Hydro, see our FAQ download available on the Case Study page.


We are fully operational!

21 February 2018

We are very happy to report that Sandford Hydro is fully operational!

After a series of thorough tests to ensure that the hydro is functioning as it should, including lots of trials to be prepared for any extreme conditions, we are running at maximum power.

All of our systems are now linked up with the Environment Agency’s remote monitoring system, which enables them to keep a close eye on the river levels at the Hydro. They can also monitor the hydro should anything shut down unexpectedly.

Why might the screws not turn all the time?

As we continue to operate a fully functional hydro for the next 40 years, there might be occasions when the screws don’t turn. These can include:

  • If we have to make minor adjustments to the operation, we will shut down the hydro for short periods of time to do this.
  • If there are extreme river conditions (which we expect to happen less than 5% of the time), the hydro will stop. For example, this could happen if the river level downstream rises too much, leaving the screws mostly underwater; in this case the screws will be stopped, as they wouldn’t generate much power in this situation anyway.
  • If the river flow drops, the hydro will automatically slow down and the number of screws turning may reduce.
  • If there is a power cut in the electricity grid, the hydro will stop automatically for safety reasons. 

For more information on how Sandford Hydro works, please have a look at our FAQ guide. As always, if there are any questions not covered there, please do get in touch at


FAQ Guide now available

15 February 2018

To answer some frequently asked questions about the Sandford Hydro project, we've produced this handy FAQ guide. Have a read and if there's anything else you'd like to know, please do get in touch at

Sandford Hydro FAQ Guide
Sandford Hydro FAQ Guide
Download now

Happy New Year! 

After an unusually dry autumn, the flow of the Thames has finally been sufficient since the 8th of December to turn the Archimedes screws and for us to carry out further tests in live conditions, which we had not been able to beforehand. 

The screws have now been operating intermittently and we got 8 days of continuous operation over the Christmas break. We had to stop operation on the 27th December due to a rapid increase in river level.

Operation has started again on the 4th of January and we need to get express permission from the EA, on a daily basis, in order to operate. This is mainly because a telemetry link requested by the EA has not been implemented yet on their side. 

We understand that the EA’s priority at the moment is to manage the river levels to avoid flooding and that they would have preferred that we carried out live tests before the river conditions got so extreme, however we cannot control the weather and the amount of water in the river went from extremely low to very high in a matter of a few days. 

The outcome we are seeking is to get the hydro operating as much as possible and do so by working closely with the Waterways Team, who have been very helpful. 

The hydro control systems are designed to cope with changing river conditions and once the telemetry link is in place this will give the EA greater visibility and comfort of what is happening in the river and this will help overall river management. 

Despite the frustration of not having the hydro fully operational, we believe that cooperation with the EA will benefit us all in the long term – we will be working with them for at least the next 40 years after all. 

We are currently able to operate when there is a lock keeper on site at Sandford Lock as this would allow immediate action if high water levels were reached. This is a temporary solution and we expect to be in full operation in the next fortnight. 

It’s worth noting that we do not expect this delay in full operation to have a negative impact on members’ financial returns – the financial model does not forecast interest payments to members in the first year of operation because of such risks at the start of operations. 

If you have any further questions regarding the Hydro or would like to know more please send them over to  Please also look out for further updates here and monthly updates in our newsletters, which you can subscribe to here

We hope to provide further information soon and a very Happy New Year again from everyone here at the Hub. 

It's great news that we're now operational and generating clean energy from the Thames. Having seen the plant through from planning to operations has been a big job, so I'm really pleased we've done it.

Adriano Figueiredo


Sandford Hydro is now commissioned

29 August 2017

Since our last update, we built all the electric connections and spent some time testing that:

  • the Hydro is properly connected to the National Grid -- which it is, so we've had sign-off on this from SSE, the distribution network operator
  • all three screws function at different speeds
  • we can operate the plant safely -- this was done by deliberately causing faults to see if our safety features would kick in as they should.

For example, we ran each screw at full speed, pulled out a critical wire and tested that they would come to a full stop in less than 2 seconds, or within a quarter turn. As you can see in this video, they do! And this second video shows them all turning.

We are now waiting for the river flow to increase, so there is enough water coming down to start turning the screws and generating energy. Our model for Sandford Hydro does take into account that we expect little or no generation over the summer months. Luckily, low river flows tend to be in the summer when our solar PV installations on local schools and businesses do best, so we are still generating clean energy throughout the year.


Still busy on site

19 July 2017

Work continues on site, where most of the tasks on the power plant have been completed. We are finishing excavations to allow water into the new inlet channel, the electrical works for the connection to the grid are built and we are working hard with SSE, who operate the local electricity distribution network, to get all the paperwork signed off which will allow us to energise the system.

We are also finishing constructing the fish pass which will allow all species of fish in the river to migrate upstream from the Lasher Weir for the first time in nearly 400 years! The pass has both concrete and naturalised sections and will be the first of its type in England.

The concrete sections upstream and downstream have already been completed -- have a look at the photo. We are now working on the banks of the naturalised sections, where we will have reeds, resting pools and spawning grounds. We hope the fish will like it.


The footbridge is back and the path open

10 May 2017

After just a week the pedestrian footbridge is back in place, as all three Archimedes screws have been moved from the Wharf in Sandford to the Lasher Weir on the Kennington side of the Thames.

This is really good news for all local walkers - we're very happy that we, with our contractors, managed to put it back so quickly. So get walking and enjoy the sunshine!


Two Archimedes Screws on the move

5 May 2017

We are really pleased with progress on site, as two of the three Archimedes screws have been floated from the Wharf in Sandford across the river to the Lasher Weir. There, a rather large crane lifts them into position within the main concrete structure.

The third screw is due to be moved next Monday morning.

We needed a small crane to put together one large enough to lift our Archimedes screws. That's because of the railway bridge which restricts access to the site.

Adraino Figueiredo Operations Director Low Carbon Hub Team 500 Adriano Figueiredo Operations Director, Low Carbon Hub


Change: Footbridge to be removed on 2 May

26 April 2017

We have had to change the timing of when the pedestrian footbridge will be removed back to early May. It will now be removed on Tuesday, 2 May, for a maximum of four weeks.

The first of the three Archimedes screws is planned to be floated on the river to the weir on 4 May, with the other two following on 8 and 9 May.

Keep an eye out on this page for further updates!

Here are the photos from the successful operation on 3 May! The bridge will be back within 4 weeks, or before then if possible.


Footbridge to be removed on 28 April

12 April 2017

The timing of when the pedestrian footbridge on the island between the Lasher Weir and Sandford Lock will be removed temporarily has changed! It has been moved forward to Friday, 28 April, instead of early May.

The bridge has to be removed to allow for the three Archimedes screws to be floated on the river to the weir where they will be installed to generate clean energy from this summer. We expect this to be happening from 3 May.

We can't say precisely when the bridge will be put back in place, but it will be for four weeks at most -- hopefully less. Maps showing diversions to local footpaths will be going up around the area and here soon.


Footbridge closure in May - early notice

31 March 2017

When we put together our project timeline (see update 9 below), we flagged up that the pedestrian footbridge at the north end of the island between Sandford Lock and the Lasher Weir will have to be removed temporarily. This will be necessary when the three Archimedes screws currently stored at Sandford Wharf are transported on the river to be installed at the Weir.

We currently expect this to happen at the beginning of May, when the footbridge will be removed and the footpath closed, for a maximum of four weeks. Hopefully it will be for a shorter period, but we can't say for sure at this point.

Signs explaining the situation will go up soon; you can download one here too. Additional notices highlighting diversions will be displayed at key points in the network of local footpaths once the bridge is actually closed.

General Poster
General Poster
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We are really sorry for this disruption to your enjoyment of the local area during the construction of Sandford Hydro and apologise in advance -- we know that many of you use that path!

Img 2244 Kat Luddecke Stakeholder Engagement Advisor


Three Archimedes screws

31 March 2017

The three Archimedes screws arrived at Sandford on 29 March, as planned. They are now on the Wharf just before the Kings Arms, waiting to be installed in the new structure on the Kennington side of the Lasher Weir. We currently expect that to be during the first week in May, but keep an eye out for updates here closer to the time.

Just to remind everyone that the fences around the screws are there for people's safety -- you are very welcome to come and have a look at them, but they are tall structures and we wouldn't want to see anyone injure themselves accidentally. So please respect the fencing and keep at a safe distance!

Thanks to Liz Shatford for this video of the delivery and to the Oxford Mail for this article.

I think people were surprised to see just how big they were. We had people on the other side of the green watching pretty much all day – they were just mesmerised.

Adraino Figueiredo Operations Director Low Carbon Hub Team 500 Adriano Figueiredo Operations Director


We're on our way

23 March 2017

The three Archimedes screws are now on their way -- looking very pretty in their water blue colour! We are expecting them to arrive at Sandford on Wednesday, 29 March. If the date changes, as it well may, we will update you here! We are also keeping local residents along the delivery route on Church Road informed, as parking and traffic are expected to be restricted during the day of the delivery and the evening before.

Sandford-on-Thames Parish Council have kindly given permission to keep the screws on the Wharf on Church Road just before the Kings Arms. The concrete structure on the Lasher Weir that will house them is coming together, but it will be still some weeks before the screws can be installed. We currently expect that to be around 24 April, when the screws will be lifted onto floating pontoons so they can be transported on the water to the construction site at the Weir for installation.

Church Road Plan Model
Download now

Say hello and getting ready for the screws

8 March 2017

Come to talk to us about Sanford Hydro and our re-opened community share offer to raise the remaining £380,000 of our original £1.2m target!

We're planning to be at the:

  • Apple Cafe at St. Swithun's Church Hall, Kennington OX1 5PL on Saturday, 11 March, 10.30am to 12.30pm
  • Talking Shop at Sandford Village Hall, Sandford-on-Thames OX4 4YN on Saturday, 19 March, 9am to 12 noon
  • Apple Cafe at St. Swithun's Church Hall, Kennington OX1 5PL on Saturday, 8 April, 10.30am to 12.30pm.

Also, we'll be starting some work on Sandford Green soon, in preparation for the screws arriving -- now looking like 29 March! Thanks to Sandford Parish Council and look out for more details here soon.

We'll also have a stall at the ATOM Science Festival on Saturday, 25 April, in Abingdon Market Place. Come and say hello!


Increased traffic next Monday!

24 February 2017

Just to let you know that next Monday, 27 February, we will have about 20 to 25 lorries coming onto the site. This is to bring quite a lot of concrete as we're now out of the hole, so to speak, and the structure is rising fast!

The lorries will be taking the usual route, from south of Kennington, turning into Sandford Lane and then down the temporary road to the construction site.


Moving on up

22 February 2017

Adriano has taken the opportunity of being on-site for one of our weekly project meetings to take some more photos to show how the structure is coming along nicely.

You can even see where the slots for the screws are being formed in what looks like a -- slightly edgy -- 'U'-shape. One of the builders is using the wooden frame to climb up higher and help ensure the concrete is poured in the right place!


Checking up on our screws

22 February 2017

Our Operations Director, Adriano Figueiredo, has been back to see how the screws are -- literally -- coming together over at the factory in Hungary. This time, Adriano had both an engineer and a designer from our civil works contractors with him, to measure and verify the dimensions of the screws and to help with the detailed planning of the installation when the screws arrive on site later this spring.

Installing the three massive screws will be the most challenging part of the build, so we want to make sure it is as well prepared as possible.

It was good to see the screws now with the blades welded on -- and to get together with everyone to review all the steps of the installation process!

Adraino Figueiredo Operations Director Low Carbon Hub Team 500 Adriano Figueiredo Operations Director


Working Saturdays

3 February 2017

If the weather allows, our contractors will keep working on building the main structure this coming Saturday. This is so we can keep making progress with the project as quickly as possible.

Access for walkers in the area won't be affected but please be extra vigilant as there'll be heavy vehicles driving up and down the temporary road! We may keep working on future Saturdays too, if we think it will help move the build on.


Getting on with laying the foundations

3 February 2017

Back on site our contractors have started work to lay the foundations for the three Archimedes screws that will power the hydro. Much of it is pouring concrete, in the area now secured with the recently completed cofferdam.

So far, about 15% of the foundations have been layed -- as they need to be sufficiently strong to hold the screws, this part of the work will continue well into April.

Of course, concrete and steel come with their own carbon footprint so we did some calculations to check how long it will take for the carbon generated in constructing the hydro to be paid back. They show the pay back period to be around 3.5 years, for a project expected to generate clean energy from the flow of the Thames for at least 40 years!

I've calculated that the pay back period for the carbon generated by the reinforced concrete and all the steel used in building Sandford Hydro is around 3.5 years. This includes the steel for the piles and screws. If you want to run your own calculations, get in touch!

James Ochiltree Projects Executive Low Carbon Hub Team 500 James Ochiltree Projects Executive


Checking up on our Archimedes screws

25 January 2017

As we're making progress on site at the Lasher Weir between Kennington and Sandford-on-Thames, the Archimedes screws are also -- literally -- coming together.

Adriano Figueiredo, our Operations Director, went earlier this month to check on how things are going at the Andritz factory in Hungary where the screws are being built. He met three of the engineers working on the screws and had a good look into the central tube of one of them, as you can see!

Can you spot 'Sandford' etched into the central tube of this screw?

Barbara Hammond Ceo Low Carbon Hub Team 500 Barbara Hammond MBE CEO of Low Carbon Hub


Piling completed in December!

20 January 2017

The noisy piling work was completed in mid-December. It had to be done to put in a temporary cofferdam. This was to enable us to start work on the concrete foundations for the turbines, to be installed on the Kennington side of the weir.

Adriano Figueiredo, our Operations Director, went out on another site visit and took some photos to show what it looks like with the piles in.

We're glad that the piling has now been finished! As you can see, the steel piles are really quite large but they're finally all in the ground. We're working hard to make the most of the short days!

Adraino Figueiredo Operations Director Low Carbon Hub Team 500 Adriano Figueiredo Operations Director



29 November 2016

We've mapped out what we expect to happen on and around the site over the coming months as the build of the hydro and fishpass progresses.

Much of the work depends on the weather (river levels, temperature, rainfall etc.), so we cannot be that precise about dates. But we hope these maps give you a better idea of some of the key steps involved in getting this community energy project completed by summer 2017.

If there are any significant changes, we will of course update the maps, so keep a look-out on this page or sign up to our project updates.

And feel free to come along to our stall at the Apple Cafe in Kennington on 3rd December!

Adraino Figueiredo Operations Director Low Carbon Hub Team 500 Adriano Figueiredo Operations Director

Sandford Hydro Timeline 1216
Sandford Hydro Timeline 1216
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Sandford Hydro Timeline 0117
Sandford Hydro Timeline 0117
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Sandford Hydro Timeline 0217
Sandford Hydro Timeline 0217
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Sandford Hydro Timeline 0417
Sandford Hydro Timeline 0417
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W/c 28th November may well be noisy again

25 November 2016

Unfortunately next week (from Monday, 28th) looks like there will be more piling, which means more noise. We know it’s not been easy for everyone affected, so are really sorry about this.

We've had a delay with a piece of equipment failing, so that’s why the piling will be continuing into another week – then it should all be done.

Our contractors won't start before 8am or go on after 5pm, and there is no piling on weekends.


Talk to us in Kennington on 3rd December!

25 November 2016

We’ll be at the Apple Café in St Swithun's Church Hall on The Avenue (OX1 5PL) from 10.30am until 12.30pm on Saturday, 3rd December.

Come to find us and hear what will be happening when, as Sandford Hydro is being built – including a fishpass to unlock the river further upstream for fish to swim up! We look forward to seeing you then.



12 November 2016

Thanks to all  59 of you who responded. The winner with 36% was Water Blue RAL 5021!



7 November 2016

We are about to order the three massive Archimedes screws for Sandford Hydro. We'd love your input on the colour of the screws. To help us choose please complete this very short colour poll -- and share it widely. 

Please respond by the end of Friday, 11th November. Thank you!



7 November 2016

We've put our heads together with our contractors and come up with a way to open the path across the field again while still complying with our Health & Safety obligations.

The main concern had been the safety of people, and their dogs, with the construction traffic on the temporary road. Our contractors will now be driving at reduced speed.

New notices with the revised footpath map will go up today! 

Sandford Hydro Footpath Map 07_11_16
Sandford Hydro Footpath Map 07_11_16
Download now


2 November 2016

Huge apologies to everyone affected by the noise from current piling work. We’re sorry, but it’s work that has to be done. The plan is to finish the piling work in the w/c 21 November. Our contractors are doing what they can to minimise noise, e.g. 

  • No work at all on weekends, and no work before 8am or after 5pm on weekdays
  • Using vibrations to pile wherever the ground conditions allow (rather than pushing them in). 

We will hold a Public Meeting soon to talk about the benefits the project is expected to generate and to answer your questions. Email us to register your interest to attend.



15 September 2016

We have put up notices in the construction area to show arrangements for footpaths while we’re on site. Our main concern is the safety of everyone – including dogs – during construction. Unfortunately this means that some areas will not be accessible while we build the hydro, as heavy construction machinery is moving up and down the temporary road. All the formal footpaths remain open.



4 August 2016

Low Carbon Hub is developing a community energy hydro project to return the Lasher Weir to its historic role as a provider of clean energy. Three Archimedes screws are expected to generate enough energy to power about 406 homes – all of Sandford or half of Kennington!

Having prepared the site in the spring, our contractors are now ready to start works on site and put in place the temporary infrastructure needed during the construction phase. We are keen to share our plans for the works and how we're trying to minimise the impact for both villages.

To find out more and stay updated you can:

  • join us at this meeting at Sandford Village Hall
  • sign up for project news via our monthly e-newsletter
  • keep visiting this page for updates!

Find out more about this community energy scheme at our public meeting on Thursday, 11 August, Sandford Village Hall, Henley Road, from 7.30 - 9 pm.

Sandford Lock Hydro will return the Lasher Weir to its historic role as a provider of clean energy. It is Low Carbon Hub’s largest community energy project to date, and a key part of our vision to create, together with local households, businesses and schools, a clean, community-owned energy system for the county.

Barbara Hammond Ceo Low Carbon Hub Team 500 Barbara Hammond MBE CEO of Low Carbon Hub

sandford hydro in numbers

  • 440 kwp installed capacity
  • 406 homes the project could power
  • 1.6 GWH of clean electricity to be produced annually
  • 2 tonnes of CO2 the project will avoid every day