Terence Lam

Information of River Thames Location : southern England Length : 346km (second longest in the United Kingdom) Source :Thames Head Mouth :Thames Estuary, North Sea Cities flow through : London, Windsor, Oxford Average discharge : 65.8 m /s 3

Importance of River Thames provide habitation, water power, food and water International trade & cultural canter -acted as a major highway

Information about Thames Barrier World's second-largest movable flood barrier Built across a 520-metre wide stretch of the river Total construction cost: around £534 million Location: downstream of central London

Reasons for building Thames Barrier Prevent London from flooding - A storm surge generated by low pressure in the Atlantic Ocean sometimes tracks eastwards past the north of Scotland -may then be driven into the shallow waters of the North Sea. Rising of water levels Historical flooding Thames flood

Design of Thames Barrier rotating gates divides the river into four 61 meter and two about 30 meter navigable spans gates are hollow made of steel (40 millimeters thick) 20.1 meters high & weigh 3,700 tones (4 central gates)

Source: Wikipedia BBC