Although walls are permanent and easy to maintain, making them higher and higher would eventually block out the Thames from view. Research led the government to decide that the best long-term solution would be a flood barrier with moveable gates built across the Thames. The former Greater London Council coordinated the barrier project with different contractors building the gates, shore machinery and upstream bank raising works.
Construction began in The barrier was finished by and first used in It was officially opened by the Queen in The Thames Barrier is part of a system of flood defences in London. Without the barrier, frequent tidal flooding of the Thames would submerge buildings along the river as well as the underground. The barrier is credited with having helped London grow into a global capital — transforming the lives of millions of people who have worked, lived in or visited London since it opened.
The barrier was built over a m wide stretch of the Thames near Woolwich in south London. It divides the river into 4 spans - each span is 61m across.
Engineers chose the location as the banks were relatively straight at this point and the chalk river bed was strong enough to support the barrier. Charles Draper came up with the concept for the barrier's flood gates, basing their design on the taps on his gas cooker.
The flood gates are circular segments and move into the raised position by rotating. The gates are hollow — they fill with water as they sink and empty as they emerge from the river. At Without the Thames Barrier, London's flood defence walls… would have to be as high as the Victorian streetlamps - effectively depriving Londoners of their river. The Thames Barrier is the second largest flood defence barrier in the world.
The Oosterscheldekering Barrier in the Netherlands is the largest. Without the barrier London landmarks such as the Houses of Parliament, the O2 arena and Tower Bridge would be submerged by flood water.
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You can change your cookie settings at any time. The Thames Barrier is one of the largest movable flood barriers in the world. 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.
Please call us or check our website for our opening times, prices, and package and conference details. Email thamesbarrierenquiries environment-agency. 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 hydrological and meteorological data is fed into the control room every minute from a wide network of tide, river, pressure and wind gauges. 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. The Thames Barrier spans metres across the River Thames near Woolwich, and it protects 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, 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. The Thames Barrier has been closed times since it became operational in correct as of November The barrier closure is triggered when a combination of high tide forecasts in the North Sea and high river flows at the tidal limit of Teddington weir indicate that water levels would exceed 4.
Future sea levels and river flows are generated by Met Office computer models and forecasting systems. This service monitors tides along the east coast of England and as far away as the Western Isles in Northern Scotland.
The Thames Barrier has been closed times since it first became operational in correct as of March The barrier is a series of 10 separate movable steel gates, standing 20 meters tall and stretching meters across the river. Each of the main gates is a hollow steel-platted structure over 20m high and weighing around 3, tonnes, capable of withstanding an overall load of more than 9, tonnes of water. When the barrier is closed, a solid steel wall sealing the upper part of the river from the sea is created, stopping water from flowing upstream towards the capital.
The gates can also be part closed in the underspill position, allowing a controlled amount of water to pass under the gate and up the river. Individual gates can be closed in ten minutes but the whole barrier takes around one hour and a half to close completely. The barrier is only reopened once the water level upstream of the barrier matches the water level downstream. When not in use, the gates rest out of sight in curved recessed concrete cills in the riverbed, which allows river traffic to pass through.
Before the barrier was built, the solution to flooding was to build higher and stronger river walls and embankments — a solution that became popular following the Thames Flood Act of and remained an accepted measure until midway through into the 20th century.
Following a report in by Sir Herman Bondi, it was decided that the best solution was bank raising and a flood barrier with movable gates built across the Thames. The Thames Barrier and Flood Protection Act gave powers to carry out this solution and led to the construction of the barrier.
The barrier was originally designed to protect London from a very large flood 1 in years up to
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