Flooding

Question 1

Human Causes

Answer 1

• Afforestation
• Impermeable surfaces
• Urbanisation
• Channelisation

Question 2

Natural Causes

Answer 2

• Melting snow/Ice
• Heavy rainfall
• Rocks act as surface run off
• Hard soil

Question 3

Types of flood management

Answer 3

• Afforestation (Soft Engineering)
• Levees (Hard Engineering)
• Dams (Hard Engineering)
• Retention Ponds (Hard Engineering)
• Flood Warning System (Hard Engineering)
• Floodplain Zoning (Soft Engineering)
• Channelisation (Hard Engineering)
• Do Nothing (Soft Engineering)

Question 4

Afforestation

Answer 4

• Trees slow down the flow of water towards the river channel and also allow more interception
• £30’000 per Hector/Ha

Question 5

Levees

Answer 5

• Increases the potential of maximum are of the river channel allowing it to hold more water before it bursts its banks
• £8000 per metre/M

Question 6

Dams

Answer 6

• Built to control discharge
• Holds back water allowing it to be released in a controlled way
• £5-25 Billion

Question 7

Retention Ponds

Answer 7

• Allows run off to be temporarily stored and in turn lessens the risk of flooding
• £25’000

Question 8

Flood Warning System

Answer 8

• Allows evacuation of areas likely to flood and therefore reduction in damage by warning people in advance
• £1.3 Million

Question 9

Floodplain Zoning

Answer 9

• Considers the floodplain and try’s to avoid building on the areas which are most likely to be flooded.
• Area closest to channel is often used for farming
• Potentially free/ Low cost

Question 10

Channelisation

Answer 10

• Reduces water friction with the bed and banks speeding up water flow
• Gets water away and downstream from an area quickly
• £500 per Metre/M

Question 11

Do nothing

Answer 11

• Accept that flooding is a natural process and allow the river to flood as it pleases without control
• Free

Question 12

Hard Engineering

Answer 12

• Expensive
• Often has negative impact on river and surrounding environment
• Works against nature
• Man made

Question 13

Soft Engineering

Answer 13

• Work with nature
• Often cheap
• Ecologically sensitive

Question 14

CASE STUDY:
-Tewkesbury floods 2007-
CAUSES

Answer 14

• Vast flat land which was fertile
• River Severn and Avon confluence
• Impermeable surfaces
• No flood defences
• Low pressure in Calais
• 140mm of rainfall in only a few hours
• In a water Basin
• Large amounts of construction on a flood plan
• Soils were already saturated
• Size of rivers weren’t big enough
• Summer was wettest recorded

Question 15

CASE STUDY:
-Tewkesbury floods 2007-
EFFECTS

Answer 15

• 3000 people without clean drinking water
• Damaged services
• Pathways flooded
• Power supplies cut off
• Residents evacuated
• All four roads into Tewkesbury were cut off
• 4000 homes and 500 businesses flooded
• Clean tap water contaminated
• Some residents were stranded
• Tourism and economy effected
• Sewerage pipes burst
• House prices dropped due to lack of insurance
• 8 weeks before water supply is restored
• Damaged infrastructure
• 8 months to refurbish the town
• People possessions ruined
• Tewkesbury became isolated

Question 16

CASE STUDY:
-Tewkesbury floods 2007-
RESPONSES

Answer 16

• Access to boats
• Doctors moved to the council offices
• Temporary shelters put in place
• Food donated
• High volume pumps used to save electricity station
• 137 portaloos deployed
• 1400 Water bousers deployed
• Boundary walls put in place
• Flood warning put in place
• £25 Million spent on roads
• Bottled water handed out (10L per person per day)
• Army deployed
• Rescue teams from Cheshire
• Residents given sandbags

Question 17

CASE STUDY:
-Pakistan floods 2010-
CAUSES

Answer 17

• Monsoon rains causes flash floods
• Near the Indian ocean so lots of evaporated water
• Groundwater and surface run off
• Indus river has a flood plain of the whole of Pakistan

Question 18

CASE STUDY:
-Pakistan floods 2010-
EFFECTS

Answer 18

• 796,095km² of land covered in water
• 14 million homeless
• Death toll 2000
• 20 million directly effected
• Asked for $460 Million relief aid, only 20% of this was received by August 2010. The UN was concerned that aid wasnt arriving fast enough
• World Health Organisation stated ‘10 million people drinking unhealthy water’
• Widespread disease such as cholera
• 84 out of 121 districts effected
• 1.8 million homes destroyed
• $4 Billion worth of damage to infrastructures, and $500 million on crops and agriculture. Overall cost= $43 Billion

Question 19

CASE STUDY:
-Pakistan floods 2010-
RESPONSES

Answer 19

• Ensure adequate public health of the flood affected population through an integrated approach or ‘Survival Strategy’ combining safe water, sanitation, hygiene and healthy nutrition levels
• Provided food assistance and other social protection measures to offer a basic safety net, especially to the most vulnerable, until peoples livelihoods are restored
• Support durable solutions through the provision of shelter assistance prioritizing shelter solutions that can span emergency shelter, transitional shelter and core housing needs.
• Restore on and off farm livelihoods, with a focus on agriculture, livestock and protection and restoration of productive assets
• Restore basic community services and supporting the re-establishment of public administration, health and education systems