Which is a natural cause of flooding?

prolonged heavy rainfall. The others are human causes.

How does urbanisation increase flooding?

It creates impermeable surfaces, so more water runs off quickly. Drains carry the water to the river very fast.

Which is a hard engineering strategy?

building a dam. It is a built structure that controls the river.

Which is a soft engineering strategy?

afforestation. It works with natural processes.

Which is an economic impact of a flood?

damage to businesses and crops. It costs money.

Why is floodplain zoning considered sustainable?

It keeps buildings away from the risk without altering the river. Nothing has to be built or maintained.

Living near rivers: opportunities and flooding

In plain words

People have always settled beside rivers, for water, food, flat land and transport. The price is that every so often the river takes the land back. Managing floods means choosing between fighting the river and making room for it.

7 things to know

Opportunities of living near a river: fertile soil on the floodplain, flat land to build on, water for drinking, farming and industry, transport, fishing, hydroelectric power, and tourism.
Hazards: flooding, bank erosion, and diseases carried by water.
Natural causes of flooding: heavy or prolonged rainfall, rapid snowmelt, steep slopes, impermeable rock, and saturated or frozen ground.
Human causes of flooding: deforestation, which reduces interception; urbanisation, which covers land with impermeable surfaces and drains; and building on floodplains.
Impacts of flooding. Social: deaths, homelessness, disease. Economic: damage to property, crops and roads, and lost business. Environmental: habitats destroyed, and pollution. Floods also bring benefits: fertile silt, and refilled water stores.
Hard engineering controls the river: dams and reservoirs, embankments, straightening and deepening the channel, and flood relief channels. It is effective but expensive, and can move the problem downstream.
Soft engineering works with nature: planting trees (afforestation), floodplain zoning to keep building away from risky land, flood warnings, and restoring rivers and wetlands. It is cheaper and more sustainable, but gives less protection.

Worked example

A town on a floodplain wants to reduce its flood risk. Evaluate building a dam upstream.

For: the reservoir stores floodwater and releases it slowly, so the town is protected. It can also supply water and hydroelectric power.
Against: it is very expensive, it floods land and forces people to move, and it traps sediment that would have fertilised land downstream.
A judgement: it protects well, but it is costly and less sustainable than a mix of soft engineering methods.

Tips and tricks

"Evaluate" means give strengths and weaknesses, and then a judgement. A list of methods with no comment stays in the lowest marks.
Sort impacts into social, economic and environmental. The syllabus uses those three headings, and so do the mark schemes.

6 questions, about 2 minutes.

It lands in your notebook with its questions as flashcards.

Living near rivers: opportunities and flooding: 6 questions and answers

These are the quiz’s questions. Do the quiz first, then come back here for the ones that got you.

Which is a natural cause of flooding?
- deforestation
- urbanisation
- prolonged heavy rainfall (the answer)
- building on a floodplain
The others are human causes.
How does urbanisation increase flooding?
- It increases infiltration.
- It creates impermeable surfaces, so more water runs off quickly. (the answer)
- It increases interception.
- It reduces rainfall.
Drains carry the water to the river very fast.
Which is a hard engineering strategy?
- afforestation
- floodplain zoning
- building a dam (the answer)
- flood warnings
It is a built structure that controls the river.
Which is a soft engineering strategy?
- embankments
- channel straightening
- a flood relief channel
- afforestation (the answer)
It works with natural processes.
Which is an economic impact of a flood?
- loss of wildlife habitat
- damage to businesses and crops (the answer)
- spread of disease
- people being injured
It costs money.
Why is floodplain zoning considered sustainable?
- It needs large concrete structures.
- It keeps buildings away from the risk without altering the river. (the answer)
- It is the most expensive method.
- It moves floods downstream.
Nothing has to be built or maintained.

6 questions

Tap an answer and you’ll see straight away whether it’s right, and why.

Worksheet

3 questions, 11 marks. Write your answers on paper, then check them.

Living near rivers: opportunities and flooding

Cambridge IGCSE Geography 0460 · 11 marks · papermunch.org

Name ______________________________ Date ______________

Explain two human causes of river flooding.[4]
Show answerHide answer
Deforestation: fewer trees intercept rain, so more water reaches the river quickly. Urbanisation: concrete and tarmac are impermeable, so rain runs straight off into drains and the river.
I got this one
Describe two soft engineering strategies for managing river floods.[4]
Show answerHide answer
Afforestation: planting trees to intercept rain and slow the flow of water to the river. Floodplain zoning: not allowing building on the land most likely to flood.
I got this one
Give three reasons why people live on floodplains.[3]
Show answerHide answer
The soil is fertile. The land is flat and easy to build on. The river supplies water. (Also: transport, fishing.)
I got this one

Answers: Living near rivers: opportunities and flooding

1. Deforestation: fewer trees intercept rain, so more water reaches the river quickly. Urbanisation: concrete and tarmac are impermeable, so rain runs straight off into drains and the river.
2. Afforestation: planting trees to intercept rain and slow the flow of water to the river. Floodplain zoning: not allowing building on the land most likely to flood.
3. The soil is fertile. The land is flat and easy to build on. The river supplies water. (Also: transport, fishing.)