FIGURE11 An artificial levee
The levee contains the water of the river if it rises above the natural height of its banks during a flood event.
Levee bank; can be built from earth, sandbags or concrete
Natural river bank
SkillBuilder discussion Concluding and decision-making, Communicating 1. What is the purpose of a levee during a flood event? 2. What materials can be used to build levee banks? 3. How does a levee help control rising water levels?
London built the Thames Barrier, a series of floodgates (see FIGURE12 ), to protect against high tides and storm surges. The gates rise at a certain water level and lower once the water recedes.
FIGURE12 The Thames Barrier
To reduce flood damage, building on flood-prone, low-lying land should stop. Brisbane City Council’s 2006 buy-back scheme allows residents in high-risk areas to sell properties, preventing future construction. Of 207 offers, only 45 were accepted before the 2011 floods.
306 Jacaranda Humanities Alive 7 Victorian Curriculum Third Edition
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