Resource 1 Preparation

Where are we looking at? Drainage basin ADrainage basin B

Drainage basin A

Drainage basin B

What differences are there? Characteristics of the basin The way it responds

Drainage Basin ADrainage Basin B Peak rainfall mm Time of Peak rainfall Peak discharge cumecs Time of Peak discharge Lagtime Description of rising and falling limbs Description of land use and size of the river from the photograph. Refer to Relief, Land Use and Vegetation. Description of drainage basin from OS map. Height of land and gradient of slopes. Of these two basins which is most likely to flood Explain your answer : Refer to interception, storage, infiltration, surface run-off, rising limb, peak discharge and river channel capacity.

Key questions What evidence is there from the map and picture to explain the shape of the hydrograph for Drainage Basin A? Refer to Relief, Land Use, Vegetation, Contour lines, Rising limb and Falling limb in your answer. What evidence is there from the map and picture to explain the shape of the hydrograph for Drainage Basin B? Refer to Relief, Land Use, Vegetation, Contour lines, Rising limb and Falling limb in your answer

What evidence is there from the map and picture to explain the shape of the hydrograph for Drainage Basin A? Refer to Relief, Land Use, Vegetation, Contour lines, Rising limb and Falling limb in your answer. The map shows contour lines close together- indicating steep slopes and the spot height shows 519m indicating high land. The area will be high land receiving higher amounts of rainfall. The steep slopes will mean water will move downhill quickly under gravity. The land use is moorland with vegetation so the vegetation will slow the waters journey to the surface a little. The moorland heather will not take up much water and the higher land will be colder meaning less evaporation- leading to more water making its way to the river quickly leading to a steep rising limb. Most water will make its way over the surface as the soil stores will fill up quickly.the map also shows a high drainage density indicating that the river will collect any rainwater quickly and be discharged.

Key Question: The landscape, vegetation and human uses of this landscape can have a huge effect on the way that the water reacts within the River Basin area. Using answers above describe how these factors change the way that the river reacts to flood events within the 2 basins. Use figures to back up your description.

Resource 2

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Resource 2

Match these up Low Probability – High Impact Low Probability – Low Impact High Probability – High Impact High Probability – Low Impact River floods rarely in a rural area, the river is surrounded by fields and the sheep get wet feet Thames Barrier is broken by a storm surge which cause the river level to increase dramatically and London to flood up to Shepherds Bush. The River floods frequently, the river is surrounded by woodland and is sparsely populated The river floods frequently and residents often evacuated by the emergency services in life boats

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River Avon, Bath If the River Avon were to flood it would only affect the river meadows at Batheaston, as there are flood- protection measures in place within the city Okavango Delta, Botswana Landlocked inside Botswana (Southern Africa) the Okavango River annually floods to create an inland delta. Whilst animals rely on this to provide water for grass to grow, very few humans live there Boscastle Floods, Cornwall, UK This small village on the North Coast of Cornwall was flooded after a sudden thunderstorm in the summer of 2004 Bangladesh Floods Bangladesh is the location for the confluence of 3 massive rivers, all draining the Himalayas. Annual snow melt, monsoon rains and cyclones all contribute to flooding

Tasks using resource 3 Spot the difference- write a different letter next to each of the differences on area 1 Describe the differences below A- in area 1 there is whereas in area 2 there is B C D E

Tasks using resource 3 Which area is more likely to flood? State two differences between Area 1 and Area 2 (One human and one physical) and explain why you think they would increase OR decrease the risk of flooding Difference 1 (human) Developed Explanation (Why it will increase/reduce the risk of flooding) Difference 2 (physical) Developed Explanation (Why it will increase/reduce the risk of flooding)

Resource 3 The two different areas have different features, some increase flood risk others decrease flood risk. Refer to precipitation, urbanisation, dams, deforestation, forestry, industry, size of catchment, relief or shape of land. Complete the table QuestionArea 1 Area 2 1 Describe and explain any features within the area which decrease the chance of flooding. Dam/reservoir – water can be stored and released when risk of flooding is past. 2 Describe and explain any features within the area that will increase the chance of flooding. 3 What exists with the area that may need protecting from flooding? 4 Does the area appear to need additional flood management? YES/NO 5 Why? Justify your answer to question 4.

Using resource 3 Area 1 is Low Probability and Low impact – give 3 reasons why Area 2 is High Probability and High Impact – give 3 reasons why 1 2 3

Resource 4- floodplain zoning Floodplain zoning is a soft engineering management strategy whose aim is to reduce flood plain development to minimise flood risk and financial loss via damage to property. Areas or 'zones' on the floodplain are identified according to their level of flood risk. The whole area may naturally flood, without risking damage to people or property.

Use this table to label the flood plain on your photocopy of Resource 4.

Flood plain hazard use The flood return period means: What features may be affected by: A 1 in 25 year flood________________________________________ A 1 in 50 year flood________________________________________ A 1 in 100 year flood_______________________________________ A 1 in 500 year flood_______________________________________ Why is the golf course most at risk and why is this ‘acceptable risk’? The factory has been located where is has because The school and town centre are located where they are because

Resource 6

Human uses of flood plains The photos show a range of different flood plain uses, list the location and use 1 Worcester UK, village photo shows church and pub

tasks 1. Describe four ways in which a flood plain is used by humans. (4) 2. Explain one reason why a flood plain is suited to each of these uses. (4) 3. Explain how flooding could impact on each of these uses. (4 ) 4. Is there a difference how MEDCs and LEDCs use flood plains? Explain why. (4)

5b. Identify the 2 uses which you think are the most appropriate ways of using the floodplain. Use: _____________________ Explain your reasons: Use: ______________________ Explain your reasons:

5c.Identify the 2 uses which you think will be in most need of flood protection. Use: ______________________ Explain your reasons: Use: ______________________ Explain your reasons:

Give two problems that could arise from having it located on the floodplain and suggest where this should ideally be located

Hard-engineering options Dam construction Dams are often built along the course of a river in order to control the amount of discharge. Water is held back by the dam and released in a controlled way. This controls flooding. Water is usually stored in a reservoir behind the dam. This water can then be used to generate hydroelectric power or for recreation purposes. Building a dam can be very expensive. Sediment is often trapped behind the wall of the dam, leading to erosion further downstream. Settlements and agricultural land may be lost when the river valley is flooded to form a reservoir.

Hard-engineering options River engineering The river channel may be widened or deepened allowing it to carry more water. A river channel may be straightened so that water can travel faster along the course. The channel course of the river can also be altered, diverting floodwaters away from settlements. Altering the river channel may lead to a greater risk of flooding downstream, as the water is carried there faster

Soft engineering 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. PlanningLocal authorities and the national government introduce policies to control urban development close to or on the floodplain. This reduces the chance of flooding and the risk of damage to property. 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

views Different interest groups have different views about flood management techniques: Governments and developers often favour large hard engineering options, such as dam building. Building a dam and a reservoir can generate income. Profits can be made from generating electricity or leisure revenue. Environmental groups and local residents often prefer softer options, such as planting trees. Soft options cause little damage to the environment and do not involve the resettlement of communities. Effective flood management strategies should be economically, environmentally and socially sustainable. Sustainable strategies allow management without compromising the needs of future generations.

Resource 6 Flood Management Strategies: For each strategy how will it work and what are its advantages and Disadvantages Other sheet For each strategy state how will it work and what are its advantages and disadvantages. *State whether it is a long term or short term advantage or disadvantage* L=Long term S= Short term