The Thames Barrier

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 follow us on Twitter @AlanBarrierEA or read our gov.uk blog posts. or like our Facebook page

Forthcoming scheduled closures

Planned tests of the Thames Barrier 2021

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

Please 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, please call us the day before to check it is going ahead.

• Wednesday - 23 March 2022 – 09:45am –to 12:15pm
• Tuesday - 19 April 2022 – 09:30am –to 12:00 midday
• Wednesday 23 March 2022 - 09:45am to 12:15pm
• Tuesday 19 April 2022 - 09:30am to 12:00 pm
• Thursday 19 May 2022 09:40am to 12:10pm
• Thursday 16 June 2022 08:55am to 11:25am
• Monday 18 July 2022 11:00am to 1:30pm
• Monday 15 August 2022 Monday 10:10am to 12:40pm

Please call us or check our website for our opening times, prices, and package and conference details.

Tel: 0208 305 4188

Email thamesbarrierenquiries@environment-agency.gov.uk

Forecasting closures

The Environment Agency receives information on potential tidal surges from weather satellites, oil rigs, weather ships and coastal stations. They can forecast dangerous conditions up to 36 hours in advance, and will close the barrier just after low tide, or about 4 hours before the peak of the incoming surge tide reaches the barrier.

They get information 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, 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, and it 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 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 205 times since it became operational in 1982 (correct as of February 2022. Of these closures, 114 were to protect against tidal flooding and 91 were to protect against combined tidal/fluvial flooding.

If you have an enquiry about the Thames Barrier, or would like to receive a project pack, email: thamesbarrierenquiries@environment-agency.gov.uk.

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) and 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

Following Covid 19, we have changed our opening times and packages. During 2021 and 2022, we will be accepting only pre booked visits.

There will be no café on site this year. We will look at the business every year with a view to reinstating the café at a later date, and will update our website accordingly.

Our outside toilets downstairs, disabled lift and car parks will continue to be open 7 days a week between 9.00am and 5.00pm.

For further enquiries, please telephone 0208 305 4188 or email thamesbarriertheview@environment-agency.gov.uk.

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 please telephone 0208 305 4188 or email thamesbarrierenquiries@environment-agency.gov.uk.

Getting to the Thames Barrier

Rail

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 & 472).

Bus routes

Bus No’s 177 and 180 via Greenwich (stop at the top of Eastmoor Street). 161 & 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.