Activity One - Why?

The causes of flooding have been debated for some time but why is it an important type of disaster to focus on? North Western Europe is relatively lucky and does not tend to suffer from hurricanes or volcanic eruptions. What we do have to worry about is the increasing frequency of our flood events. Watch the youtube clip below and make notes on the causes and consequences of flooding in Europe in 2021.

Useful Resource

Activity Two - Magnitude and Frequency

As you are now aware hydrographs are critical in aiding Flood Agencies to predict when and where the next major flood event may occur. Generally the stronger the magnitude the lesser the frequency which is why severe floods are often referred to as a 25 or 50 year flood event. This can be illustrated in the graph below.

• • • 1. Spend 2 minutes on the internet gathering headlines of strong magnitude and low frequency flood events.

      2. Describe the graph below.

      3. Read the article in the 'Useful Resource' box and make notes on why the term '100 year floods' is disliked by hydrologists.

Activity Four - Deforestation

Whenever something is built it is inevitable that trees will be chopped down to make way for the new building or road. Unfortunately as soon as you deforest an area the interception rates will be reduced, the infiltration rates may decline and this can cause an increased amount of overland flow. To assess the impact that deforestation has on flooding answer the following questions.

• • 1. How can deforestation make flooding worse?

    2. Read the article in the 'Useful Resources' box and create a detailed examples of how deforestation can impact flood risk.

    3. Find an example of where afforestation has been used as a form of management to reduce the risk of flooding.

    4. How does deforestation impact the distribution of floods?

    5. How does deforestation impact the frequency of floods?

    6. How can deforestation impact the magnitude of floods?

Useful Resources

Reuters - Deforestation and Flooding in Kashmir

The Guardian - Planting more trees can reduce UK's flood risk, research shows

Activity Five - Flood Management

Many believe that flood management is a way to try and stop the issue of flooding but in some instances it can actually make things worse. If schemes are not maintained then there is a chance that dams can be breached and levees can burst. So what can actually be done to try and prevent flooding and how successful are those schemes?

• • 1. Describe four different ways that a river can be managed.

    2. Create a detailed example of how channel modification has actually made a flood worse.

    3. Create a detailed example of how channel modification has actually made a risk area less problematic.

    4. How does flood management impact the distribution of floods?

    5. How does flood management impact the frequency of floods?

    6. How can flood management impact the magnitude of floods?

Useful Resources

Temblor - Flooding made worse on the Mississippi

River Management effecting the location of floods