Flood Management

Question 1

Advantages of levees and embankments

Answer 1

Artificial levees can be built along river banks so that if the river floods, the water will not be able to breach the wall and cause damage.

Question 2

Disadvantages of levees and embankments

Answer 2

Levees can be expensive and can spoil the look of rivers.

Question 3

Advantages of straightening and deepening

Answer 3

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

Question 4

Disadvantages of straightening and deepening

Answer 4

Altering the river channel may lead to a greater risk of flooding downstream, as the water is carried there faster.

Question 5

Pros of washlands

Answer 5

These are areas of land where water can wash into during a flood. They are usually found in the lower course of a river. Sluice gates will be opened to allow excess water to flow into the area and flood marginal land.

Question 6

Cons of washlands

Answer 6

It is not always easy to find acceptable areas for this to happen – especially in areas where there are many cities.

Question 7

Pros of afforestation

Answer 7

Trees are planted near to the river.
This means greater interception of rainwater and lower river discharge.
This is a relatively low cost option, which enhances the environmental quality of the drainage basin.

Question 8

Cons of afforestation

Answer 8

cannot prevent flooding but it can help reduce its likelihood.