Most Common Causes of Flooding Statistics
First of all, it’s important to know that flooding can happen for a multitude of reasons. Here are the most common:
- Fluvial flooding – when rivers, lakes and other bodies of water overflow, either due to rainfall or drainage from the surrounding land.
- Coastal flooding – when high tides, storms, tsunamis and other natural disasters cause water from the sea to flood the land. This is usually the result of atmospheric pressure coinciding with a high tide.
- Surface water flooding (also known as pluvial flooding) – an occurrence that is hard to predict, this occurs when rainwater fails to drain away sufficiently.
- Sewer flooding – this takes place when sewers are blocked or overwhelmed by the water pouring in. This can cause the surrounding area to become contaminated, and is potentially very hazardous to health.
- Reservoir flooding – when a dam bursts and the contents of a reservoir cause damage to the surrounding area.
- Groundwater flooding – when the ground becomes so saturated with water that it rises above the surface. This usually occurs in areas underlain with permeable rocks.
- Flash flooding – this is usually caused by periods of heavy rain or meltwater, and can create walls of water from 10 to 20 feet high.
Of course, it’s difficult to predict where flooding will next occur, as 25% of activity actually takes place outside areas formally designated as being flood prone.