If there are prolonged periods of heavy rainfall, the ground can become saturated, making water flow more quickly to the river. This happens in the UK Winter; bands of depressions passing over bring continuous heavy rainfall.

If there is a cloudburst during a thunderstorm, rain droplets will be too large to sink into the ground straight away. They flow straight into the river instead. Sudden bursts of rain affect the infiltration rate of the soil. This causes flash floods.

Sudden rises in temperature can cause ice to thaw quickly and flow into the river.

River channels that contain high amounts of deposited silt can become blocked, meaning they are more likely to flood.

Causes of Flooding