The Thames Barrier

How the Thames Barrier works, and when it is scheduled to close.

Applies to England

The Thames Barrier is one of the largest movable flood barriers in the world. The Environment Agency runs and maintains the Thames Barrier as well as London’s other flood defences.

You can:

Photograph of the Thames Barrier

The Thames Barrier

Forthcoming scheduled closures

Planned tests of the Thames Barrier 2024

The Barrier is operated once a month for maintenance and test purposes. Details of the next planned closures are listed below:

  • Wednesday 8 May 2024, 07:55 to 10:25
  • Monday 10 June 2024, 09:40 to 12:10
  • Tuesday 9 July 2024, 09:35 to 12:05
  • Thursday 8 August 2024, 09:50 to 12:20
  • Monday 9 September 2024, 10:50 to 13:20
  • Sunday 6 October 2024, 09:30 to 19:30

The annual closure of the Barrier is scheduled on Sunday 6 October 2024, from 9.30am to 7.30pm.

Note these times may change as a result of a particular experiment or test that engineers need to carry out or because of the weather. The closure and reopening of the gates may start up to an hour before the listed times. Occasionally, closures may be cancelled at short notice due to the Thames Barrier being closed in that month for flood defence purposes or navigational reasons. If you plan to come and watch a test closure, call us the day before to check it is going ahead.

You can call us on 0208 305 4161 or email for our opening times, packages prices and conference details.

Forecasting closures

The Environment Agency receives information on potential tidal surges from:

  • weather satellites
  • oil rigs
  • weather ships
  • coastal stations

They can forecast dangerous conditions up to 36 hours in advance. The barrier will close just after low tide, or about 4 hours before the peak of the incoming tide surge reaches the barrier.

Information comes from a range of mathematical computer models that forecast expected sea and river levels. This is supplemented by data from the Met Office and real-time information provided by the UK National Tidegauge Network. This hydrological and meteorological data is fed into the control room every minute from a wide network of tide and river pressure and wind gauges.

The decision to close, or not, is based on a combination of 3 major factors:

  • the height of the tide (usually a spring tide) measured at the Thames Estuary
  • the height of the tidal surge, which naturally accompanies each tide
  • the river flow entering the tidal Thames, measured as it passes over Teddington Weir

Find up to date data for river and sea levels at the Thames Estuary and Teddington Weir.

The barrier has no individual trigger level for closure. The closing process is guided by a mathematical matrix that considers the river flow, tide and surge at the time. The final decision for closure lies with the Thames Barrier Duty Controller.

How the Thames Barrier works

The Thames Barrier:

  • spans 520 metres across the River Thames near Woolwich
  • protects 125 square kilometres of central London from flooding caused by tidal surges

It has 10 steel gates that can be raised into position across the River Thames. When raised, the main gates stand as high as a 5 storey building and as wide as the opening of Tower Bridge. Each main gate weighs 3,300 tonnes.

The barrier is closed under storm surge conditions to protect London from flooding from the sea. It may also be closed during periods of high flow over Teddington Weir. This is to reduce the risk of river flooding in some areas of west London including Richmond and Twickenham.

The Thames Barrier will then remain closed over high water until the water level downstream of the Thames Barrier has reduced to the same level as upstream. This is a managed process to provide for different circumstances, and takes about 5 hours. The Thames Barrier is then opened, allowing the water upstream to flow out to sea with the outward bound tide.

You can watch a video that shows how the Thames Barrier works:

a video of how the Thames Barrier works

Thames Barrier closures

The Thames Barrier has been closed 221 times for flood defence purposes, since it became operational in 1982 - correct as at 16 April 2024. Of these closures:

  • 119 were to protect against tidal flooding
  • 102 were to protect against combined tidal/fluvial flooding

Thames Barrier closures

If you have an enquiry about the Thames Barrier, or would like to receive a project pack, email:

The future of the Thames Barrier

The Thames Estuary 2100 plan sets out how flood risk will be managed in the Thames estuary to the end of the century and beyond. It also recommends what actions the Environment Agency and others will need to take in the:

  • short term (the next 25 years)
  • medium term (the following 15 years)
  • long term (to the end of the century)

The plan is based on current guidance on climate change, but is adaptable to changes in predictions for sea level rise and climate change over the century.

More information can be found on the Thames Estuary 2100 page.

Visiting the Thames Barrier

New Thames Barrier cafe and information centre

The View and Information Centre (Thames Barrier Estate)

The Thames Barrier Information Centre is a small exhibition where you can learn about the construction of the Thames Barrier and how it works. There is a working model of the Thames Barrier and virtual technical tour along with other films and displays about flooding and the environment.

Each package has a personal guide for your group who will show you around the Thames Barrier Estate.

Our guides will cover topics including the history of the river and the risk of flooding in London, the environment and wildlife of the Thames.

Packages for group talk – available every day – need to book in advance:

  • Economic package – up to 15 people, all ages - £175.00
  • Child group talk – up to 30 children - £201.00
  • Child luxury group talk – with activities, up to 30 children - £225.00
  • Adult group talk – up to 30 people - £225.00
  • Technical presentation – over 16 years old, up to 30 people - £250.00

Note there is no access on to the Barrier.

If you would like to book one of our packages, send an email to Note we need at least a week to process any booking form, as our guides are available just when requested.

The Thames Barrier Information Centre will be open only on Saturdays from 6 April to 26 October 2024. There is no need to book in advance to visit it. The ticket can be bought at the entrance, from 10:30 to 15:30hours.

Tickets prices:

Adult: £6.00

Senior/Student: £5.50

Child: £4.80 – Child under 5 years old is free.

Disabled: £4.50

Family ticket: £16.00 (2 adults + up to 3 children)

Our outside toilets downstairs, disabled lift and car parks will continue to be open 7 days a week between 9am and 5pm.

For further enquiries, telephone 0208 305 4161 or email

Conference room hire

The Thames Barrier View Conference Centre also has rooms to hire that offers spectacular views of the Thames Barrier and River Thames. The rooms are light and spacious and offer various room layouts to suit all occasions:

  • conferences
  • meetings
  • receptions
  • workshops
  • wakes

For prices, e-mail us:

Getting to the Thames Barrier


Charlton station is situated on Woolwich Road and is approximately a one mile walk from the Thames Barrier Site. Woolwich Dockyard station is situated near Church Street and is within walking distance. Woolwich Arsenal station is the most convenient station to take a taxi to the Barrier Site.

London Underground North Greenwich (Jubilee Line)

The station is approximately 2 miles from the Thames Barrier and only 5 minutes by taxi or bus (161 and 472).

Bus routes

Bus No’s 177 and 180 via Greenwich (stop at the top of Eastmoor Street). 161 and 472 from North Greenwich tube station.

London City Airport

The City Airport is situated in North Woolwich only a short distance from the North Woolwich Ferry crossing.

Published 25 April 2014
Last updated 29 April 2024 + show all updates
  1. Updated the planned test/closures, number of times the Thames Barrier has been closed and Thames Barrier closure graphics.

  2. Updated graphics, number of times the Thames Barrier has been closed as at 1 April 2024 and added the reason 'for flood defence purposes'.

  3. Updated Barrier closure dates and when the Thames Barrier Information Centre will be opened between April and October 2024. Also updated ticket prices for individuals and group bookings.

  4. Removed the paragraph "Unfortunately, we are not able to offer a walk-in visit, However, you can visit the site, see the Barrier and there is plenty of information about the Barrier on the windows at The View" as they now offer walk-in visits again.

  5. New closure dates and admission prices for 2023

  6. Additional information added about the annual closure of the Barrier

  7. Information about test closures updated

  8. Updates to opening times, captions, visiting information, tour packages and contact details

  9. Barrier test dates updated

  10. Additional date added to list of test closures, contact phone numbers updated

  11. New barrier test-closure dates added 22/02/22

  12. Closure graph updated

  13. Closure dates and graphs updated

  14. Barrier closure information and graph updated 09/11/21

  15. Out-of-date graph showing Barrier closures by flood season replaced with latest graph 04/11/21

  16. Updated the barrier test dates and closure numbers.

  17. Day corrected for Nov 9 barrier closure

  18. Test closure and visiting information updated 14/09/21

  19. Update to opening times in 'Planned Tests of Thames Barrier 2021' section - past dates deleted, new dates added. Email address corrected

  20. Barrier closure details updated and corresponding bar graph replaced with updated version. Explanation of what happens during annual closure removed temporarily pending finalisation of plans for September closure

  21. Out of date (April 21) barrier closure time deleted, reference to booking form for conference centre deleted along with booking form - 7/5/21

  22. Figures for number of barrier closures updated and up-to-date graph of same uploaded 13/04/21

  23. café details and opening information updated along with group visits information, out-of-date closure times deleted 07/04/21

  24. additional 2021 barrier closure times added 29/01/21

  25. Dates for forthcoming scheduled closures, number of times gates opened amended, reference to the annual test closure removed

  26. Additional information added to Annual Full Tide Test Closure section, detailing limitations resulting from coronavirus for the October 4 closure Dates deleted for closures that have already taken place.

  27. Out-of-date link deleted 07/07/20

  28. Café and information centre opening times updated 6/07/20

  29. Barrier opening history updated 16/06/20

  30. Opening times for café and information centre updated 24/03/20

  31. Note about closure of café and information centre added 19/03/20

  32. New dates for forthcoming scheduled closures added 12/02/20

  33. Amendments to 2020 opening times added 24/12/19

  34. Opening times and contact email address updated 12/12/19

  35. Disabled access information updated 17/10/19

  36. Visitor centre information updated 16/10/19

  37. Note added 08/10/19 advising disabled lift to visitor centre out of order

  38. Updated to reflect that today's full test closure has been cancelled.

  39. Information updated 19/09/19

  40. Changes to opening times and test closures, additional information about full test closure added 30 August 2019. Additional information about disabled lift not working added 04/09/19 Additional information and link added 13/09/19 Opening times and information about disabled lift added 06/09/19

  41. Update to disabled lift opening made 6 August 2019.

  42. New dates for test closures added 25 July 2019.

  43. Data uploaded 3 July 2019.

  44. Amendment to the disabled access information 9 May 2019.

  45. Updates to information Centre made 9 May 2019.

  46. Amendments made to opening times and group bookings section 17 April 2019.

  47. Updates to data and graphics made 27 March 2019.

  48. New graph and data uploaded 28 February 2019.

  49. Changes made 9 January 2019.

  50. New booking form uploaded 18 December 2018.

  51. New Booking Form uploaded 13 December 2018.

  52. Test closure cancelled for 13 December 2018.

  53. New opening times added on 20 November 2018.

  54. Update to closure dates made 29 October 2018.

  55. New information added 8 October 2018.

  56. Updates to information made 27 September 2018

  57. Information on disabled toilet added.

  58. Timings for the Thames Barrier annual closure added

  59. Additional test closure dates added 31 July 2018

  60. Disabled lift now working.

  61. Details on the opening of the new Cafe and Information Centre.

  62. New information for the Thames Barrier Information Center and Cafe.

  63. New dates for test closures added.

  64. Refurbishment of cafe delayed until June 2018.

  65. Numbers of closures updated.

  66. Two closures added to closure total.

  67. Correction to barrier closures.

  68. Information on the refurbishment of the Thames Barrier Information Centre and cafe.

  69. Data update 10 October 2017.

  70. Information about finding out if the Thames Barrier is closed via Floodline removed as service is no longer available.

  71. Thames Barrier Annual closure event information removed.

  72. New test closure dates, Cafe closing for refurbishment dates changed and warning to users of wheelchairs at the Annual Closure about access to river bank.

  73. Cafe opening at 9am on the Annual Closure day.

  74. Cafe opening times updated

  75. New information on Thames Barrier Annual Closure

  76. New times added for cafe and information centre.

  77. Taken out that the disabled lift is broken as now fixed.

  78. Information on disabled lift being out of order.

  79. New dates for Thames Barrier closures and group talks added

  80. Notice that the Information Centre will be closed between 30 October 2017 and 28 January 2018 for refurbishment.

  81. Updated opening times to cafe and Information Centre, new group talks dates added

  82. Tall ships dates and the 2017 Thames Barrier annual closure date added.

  83. Cafe opening times updated.

  84. Updated information on group talks

  85. New opening times added.

  86. New information added.

  87. November to March closure dates and information about the Open Day on 2nd October added.

  88. Updated closure dates.

  89. Special offers for Father's Day at the Information Centre.

  90. New group bookings added.

  91. New Thames Barrier Information Centre group talk dates, price list and booking form added.

  92. Notice of event at Information Centre.

  93. Annual closure times for 2016 added.

  94. Updated timetable for group talks.

  95. Visiting the Thames Barrier section has been updated.

  96. Details added about the annual closure.

  97. Details on the annual closure have been added.

  98. Updated closure times and group talk sessions.

  99. In summer 2015, the Information Centre is open 7 days a week during the school holidays.

  100. The test closure dates have been updated, and there is a new link to our blog posts.

  101. New information for group tours of the exhibition centre.

  102. New Barrier closure information.

  103. Updated planed closure dates

  104. Thames Barrier Information Centre prices from April 2015.

  105. Information on group talks added.

  106. Updated 'forecasting closures' section.

  107. Added new closure dates for 2015.

  108. First published.