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Published byBlaze Charles Modified over 7 years ago
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Which flood? Boscastle 2004 Bangladesh 2004 Slow onset Flood
Flash flood Bodin moor- slate and shale- impermeable area 70% of land less than 1m above sea level The river has been diverted for irrigation which means it silts up easily and therefore carries less water Hurricane Alex had oved across creating consistently wet conditions Confluence of 2 rivers 500mm in 4 hours Water was flowing 64kph Monsoon arrived early. Heavy rain fell from late June Melting of snow in the Himalayas The bridge created an artificial dam trapping material 80% of the country is a flood plain
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The 2004 floods Review and reflect Bangladesh Flood 2004
The 2004 floods lasted from July to September and covered 50% of the country at their peak. The Monsoon arrived early and heavy rain fell from late June. By early July, the Brahmaputra and Meghna Rivers had risen above their danger levels. A week later the flood waters have drained southwards and the capital city of Dhaka had flooded. The flood waters had over topped many flood protection embankments, inundating areas not provided with storm drainage systems. By Mid August, the flood waters had fallen in most areas, leaving contaminated mud and general destruction. Review and reflect What are the most important facts you need to gain from this.
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Review and reflect Bangladesh Flood 2004 Effects of the Flood
½ Dhaka covered in sewage. 1.5 million women and children at risk of malnutrition. 766 killed 30 million people affected The rivers deposited mud and silt it was carrying everywhere which then became contaminated. Review and reflect Add any of these to it as well If you haven’t already.
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Managing a flood risk There were 2 approaches;
Bangladesh Flood 2004 Managing a flood risk Page 24-25 There were 2 approaches; Soft engineering- working with nature to reduce flood risk and reduce damage Hand engineering- building structures to reduce the flood risk Preparedness programme: - Dhaka integrated Flood protection project: - Orange gcse ocr textbook
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Review and reflect Correct the answers:
Bangladesh Flood 2004 Correct the answers: Cluster Villages are located 5 m above sea levels. Slope Protection to reduce deposition. Dhaka Integrated Flood Protection Project was set by Oxfam. The Preparedness programme was a hard engineering strategy. Review and reflect
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Define the key term in the question.
Bangladesh Flood 2004 Describe some of the advantages and disadvantages of different ‘hard engineering methods’ designed to reduce river flooding. (6 marks) Define the key term in the question. What hard engineering strategies did Bangladesh use? What issues are there when using these?
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The 2004 floods Review and reflect Boscastle Flood 2004
Add detail to your sheet on anything you remember from this or that you have learnt from the card sort at the beginning. The 2004 floods Review and reflect What are the most important facts you need to gain from this.
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What does this figure represent?
Boscastle Flood 2004 What does this figure represent? 7 5 90 16 7 mile storm 5 inches of rainfall 90% of economy based on tourism 16th august was when the flood occurred.
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Print this out so students can use it to complete the tables describing the causes of the flood.
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Effect on lag time and peak flow Relief Very steep slopes
Boscastle Flood 2004 Complete the table using your understanding of hydrographs Factor Description Effect on lag time and peak flow Relief Very steep slopes Woodland cover Removed from the highest land. Rock Type Impermeable geology, clay and shale.
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Effect on lag time and peak flow Relief Very steep slopes
Boscastle Flood 2004 Factor Description Effect on lag time and peak flow Relief Very steep slopes Rapid surface run off. Short lag time, high peak flow. Woodland cover Removed from the highest land. Increase surface run off as less interception. Higher peak flow Rock Type Impermeable geology, clay and shale. Less infiltration, higher surface fun off, higher peak flow.
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The Effects Review and reflect 25 business properties were destroyed
Boscastle Flood 2004 The Effects 25 business properties were destroyed 50 buildings flood damaged 4 footbridges were washed away Visitor centre destroyed Stress and anxiety of local people Insurance companies paid out an estimated £20 million to repair damaged property. Review and reflect What are the most important facts you need to gain from this.
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Responding to the flood- planning for the future.
Boscastle Flood 2004 Responding to the flood- planning for the future. After the 2004 flood in Boscastle the Environmental Agency investigate the causes of the flood and found a number of human factors that contributed to the flood risk. Building of low bridges- trapped boulders Allowing trees to grow alongside the river Narrowing of channels Building along the river Removing vegetation from the sides of the valley How would each of these work- have a conversation about them. Bonus: How can it affect processes further downstream the river?
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Define what physical causes mean.
Boscastle Flood 2004 Explain the physical causes of floods (6) Define what physical causes mean. What were the physical causes for Boscastle?
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Define what a response is. Include at least 3 responses.
Boscastle Flood 2004 Bangladesh Flood 2004 Use a case study to describe the responses to river flooding (8) Define what a response is. Include at least 3 responses. Name a response, explain how it works, link back to the issue it solves.
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Water transfers What is Kielder Water? How can the reservoir be used?
Kielder Reservoir Water transfers What is Kielder Water? How can the reservoir be used? Why was the area chosen? Why was the reservoir needed? Advantages of the reservoir? Disadvantages of the reservoir. Play for 2 mins- get students into groups- each in control of a section. Use it to create a case study sheet on Kielder Reservoir. Question 1- low ability, Question 2-4 middle
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