Natural ways flood risk can be increased include:
- heavy rainfall caused by depressions causing heavy, continuous rain which saturates the soil. The land can no longer absorb water as it is saturated increasing surface run-off, higher river discharge and flooding.
- sudden downpours occurring following a very dry period can lead to flooding because the surface is baked hard. Surface run-off occurs as water cannot infiltrate leading to higher river discharge and flooding.
- sudden snowmelt releases stored water that flows over the land as surface run-off
- the loss of vegetation cover through drought or disease can lead to flooding as less interception occurs so more precipitation reaches the surface leading to increased surface run-off.
Find out more about human and physical causes of flooding.