1. Objectives..describe and explain hard and soft flood prevention strategies Page 110-111 GCSE Geography AQA A

2. Hard engineering options: Flood embankment

3. River engineering: Widening or deepening the channel will allow the river to carry more water. Straightening the channel allows water to travel faster along the course. Advantage - The channel course of the river can also be altered, diverting floodwaters away from settlements. Disadvantage - Altering the river channel may lead to a greater risk of flooding down stream, as the water is carried there faster.

4. Dam construction: Dams control the amount of discharge. Water is held back by the dam and released in a controlled way. This controls flooding. Advantage - This water can then be used to generate hydroelectric power or for recreation purposes. Disadvantages – Expensive - Sediment is often trapped behind the wall of the dam, leading to erosion further downstream. - Loss of settlements & agricultural - Loss of settlements & agricultural land when the river valley is flooded

5. Flood wall These are built to protect buildings, industry or roads These are built to protect buildings, industry or roads

6. Storage areas Provide temporary storage for water pumped from a river at risk from flooding Provide temporary storage for water pumped from a river at risk from flooding

7. Barriers e.g. Thames barrier Thames Barrier animation

8. Soft engineering options: Flood abatement Flood abatement Trees are planted near to the river = greater interception = lower river discharge. Afforestation: Trees are planted near to the river = greater interception = lower river discharge. Advantage – This is a relatively low cost option, which enhances the environmental quality of the drainage basin.

9. Flood proofing

10. Flood Plain zoning Local authorities and the national government introduce policies to control urban development close to or on the floodplain. Advantage - Reduces the chance of flooding and the risk of damage to property. Disadvantage - There can be resistance to development restrictions in areas where there is a shortage of housing. Enforcing planning regulations and controls may be harder in LEDCs.

11. Flood prediction and warning

12. Washlands Managed flooding (also called ecological flooding) Managed flooding (also called ecological flooding) The river is allowed to flood naturally in places, to prevent flooding in other areas - for example, near settlements.

13. Managing river flooding 1. Define hard engineering 2. Describe 3 hard engineering techniques and explain how they reduce the impacts of floods 3. Repeat 1 and 2 for soft engineering

14. Flood shelters in Bangladesh

15. The 1999 Bangladesh Flood Action Plan ProposalDescriptionAdvantageDisadvantage Flood sheltersBuild 5,000 shelters in areas at risk Easy to build and saves lives Doesn’t protect people’s property DamsBuild to hold back monsoon rains Water could be used for irrigation and HEP Highly expensive to construct River embankments Complete along all main rivers up to 7m in height Prevents river overflow and serious flooding Restricts access to rivers for fishing people

16. DVD Notes - Flooding in Bangladesh Management strategyHow it worksAdvantagesDisadvantages Hard engineering Faruks fish Moshiur’s pumpkins Noor’s super ducks

17. Questions A) From page 45 Write 2 lists of the hard and soft flood prevention strategies used in Bangladesh. B) Which flood prevention techniques contribute most to sustainable development and why? C) Which of the schemes do you think would be the most successful in reducing the flood risk? D) Why is it harder to limit the impact in LEDCs?....... …funding... workforce …equipment … expertise