The Thames

"The isle of Wonder" video from the 2012 Olympics opening ceremony gives students a fantastic overview of the river Thames from its source to the Thames Barrier. Danny Boyle's "Isle of Wonder" Olympics 2012The importance of the Thames Barrier to the City of London cannot be understated considering the recent tidal surges and flooding. So what is the Thames Barrier and how does it protect Londoners?

Thames Barrier

Potentially flooded Area if no Thames Barrier

The Thames Barrier protects over a Million people in the City of London against incoming tidal surges which travel upstream and have the potential to flood the city. During the present conditions of heavy rainfall and upstream flooding the Barrier is extremely important in regulating water levels in the Thames and keeping the City of London dry. Twice daily the fresh river water of the Thames is met by the high tides of the North Sea which can cause the water level to vary by up to 7 metres. The effects of extremely high tides and tidal surges are mitigated by the Barrier. The Barrier itself crosses a 520 meter section of the river. Once in the closed position the gates are 20 meters high and can hold back 9,000 tonnes of water each. This protects the City as the tidal waters would slow down the drainage of the already swollen river. As the tide goes out the barrier is opened and the river can drain as normal. Below is a video and a graph to help you understand this vital river management system.

Excellent article by Channel4 "Is London in Danger"