Rivers and Flooding

Question 1

Define erosion

Answer 1

The wearing away of rock and soil found along the river bed and banks.

Question 2

What is attrition?

Answer 2

Rocks being carried by the river smash together and break into smaller, smoother and rounder rocks.

Question 3

What is abrasion?

Answer 3

Rocks carried along by the river scrape along the river and wear away.

Question 4

What is solution?

Answer 4

Soluble particles are dissolved.

Question 5

What is hydraulic action?

Answer 5

The force of the river against the banks can cause air to be trapped in cracks and crevices. The pressure weakens the banks and gradually wears it away.

Question 6

What is transportation?

Answer 6

Transportation is the movement of sediment along a river course.

Question 7

What is suspension?

Answer 7

When fine, light material is carried along by the river.

Question 8

What is traction?

Answer 8

When large boulders and rocks are rolled along the river bed.

Question 9

What is a solution? (transportation)

Answer 9

When minerals are dissolved in the water. This makes a chemical change.

Question 10

What is saltation?

Answer 10

When small pebbles and stones bounce along the river bed.

Question 11

Name 5 causes of flooding.

Answer 11

1. Heavy rainfall
2. Steep land
3. Built up areas
4. Cutting down trees
5. Lots of impermeable ground

Question 12

Name 8 effects of flooding.

Answer 12

1. Death
2. Homes damaged
3. People without access to drinking water
4. Risks of diseases spreading
5. Schools and hospitals difficult to get to.
6. Bridges swept away
7. Transport is difficult
8. Farmland lost

Question 13

Name 6 responses to flooding.

Answer 13

1. Charities send aid
2. Governments of other countries send help/money
3. People are evacuated to safety
4. Temporary homes set up
5. Clean drinking water provided to people
6. Bridges and roads repaired

Question 14

What is hard engineering?

Answer 14

Physically changing the shape of the river or building structures to prevent flooding.

Question 15

Name 4 examples of hard engineering.

Answer 15

1. Dams
2. Embankments
3. Flood walls
4. Straightening and deepening the river channel.

Question 16

What are dams?

Answer 16

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.

Question 17

What are embankments?

Answer 17

Embankments are mounds of earth built up at both sides of a river to increase the amount of water that the river can hold.

Question 18

What are flood walls?

Answer 18

These are walls built along a river to protect vulnerable areas from water damage e.g. housing.

Question 19

How does straightening and deepening the river channel prevent flooding?

Answer 19

Making rivers straight means that the water will flow more quickly through this part of the river, giving it less chance to fill up and flood. Rivers can be made deeper in order for them to hold more water.

Question 20

What is soft engineering?

Answer 20

Working with the natural environment to prevent flooding or flood damage.

Question 21

Name 3 examples of soft engineering.

Answer 21

1. Land-use zoning
2. Afforestation
3. Warning systems

Question 22

What is land-use zoning?

Answer 22

This is when more important buildings are built far away from a river to prevent damage (e.g. hospitals) whereas less important land such as football pitches are built closer to the river as they will not be faced by flooding as much.

Question 23

How does afforestation prevent flooding?

Answer 23

Trees are planted near to the river. This increases the amount of water absorbed by the trees so less water reaches the river. This is a relatively low cost option, which looks natural.

Question 24

How do warning systems prevent flooding?

Answer 24

People are warned by radio or TV if there is a chance of a flood. This means they have time to prepare and protect their homes from flood damage.