Summary: The Thames Barriers

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The Thames barrier is a barrier system that consists of 2 different types of gates: falling radial gates and rising sector gates. The falling radial gates are held in position over the river and are non-navigable. The Rising sector gates rest on the river beds allowing the traffic to pass over them in the open position. The gates are rotated by hydraulic cylinders and the whole barrier takes approximately one and a half hours to close, usually taking place after low tide. The barrier creates a solid wall preventing the water from flowing upstream towards the capital. The four main gates span 61m and each is 20m high, capable of holding back loads of 9000 tonnes. There is an under-stream position which allows steady water flow to assist with …show more content…

The Thames barrier has been proved necessary on several occasions; it was closed 40 times between the start of the year and 14th February this year, nearing the annual recommendation of 50. To add perspective, in the whole decade of the 1980s, the barrier had only been closed 4 times, highlighting the increasing need for it given the changing climate. (Hanlon, …show more content…

Despite this the Thames barrier is expected to provide us with a strong defence than initially predicted as they had planned for an annual increase in sea levels of 8mm but it is currently increasing at a rate of circa 6mm per year. (Met Office, 2010) The main threats to London come from the storm surges and global warming (involving both thermal expansion and contributions from melting polar ice caps). Climate change also threatens to increase the frequency at which storms occur in London, adding further to the risks faced. (Marsh, n.d.)
The importance of the Thames barrier is emphasised in recent figures which suggest that the failure of the Thames barrier could lead to the flooding of around 100,000 homes in east London and Greenwich. The risk of failure is increasing with the increased usage and closing as this affects the maintenance systems. (Virtue, 2014) The Thames barrier also has the secondary purpose of controlling outflow of water due to heavy rainfall which is becoming more prominent and it has shown its usefulness in this situation, this year particularly. (Clark and Correspondent,

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