Flooding

Question 1

What are floods?

Answer 1

Temporary areas of water
Cover normally dry land
Occur in low lying areas usually
Many factors cause flooding (physical/human causes)

Question 2

Name 3 physical causes of flooding

Answer 2

HEAVY RAINFALL- excessive runoff that water can’t infiltrate
SATURATED SOIL- no more infiltration can take place. Area will overflow.
IMPERMEABLE ROCK- rocks with no pore spaces to take water. Reduces infiltration, likely to move to river as run off.

Question 3

name 2 human cause of flooding

Answer 3

URBANISATION - concrete + tarmac that causes infiltration difficulties. Moves as run off. Flood occurs
DEFORESTATION- less water used by vegetation. Less interception means more run off. Floods occur.

Question 4

Give examples of how we can prevent flooding.

Answer 4

LEVEES- work as physical wall/barrier. water can’t permeate
DAMS- barrier to restrict flow of downstream water
DEEPEN RIVER CHANNEL- can carry more water
CONTROL LAND USE AROUND RIVER- e.g trees can be planted near to ensure interception is present.