Protecting your home and community

Know Your Flood Hazards

It’s Wednesday of National Flood Safety Awareness Week

Flood marker

Photo Credit: Greenpeace

A flood is defined as any high flow, overflow, or inundation of water that causes or threatens damage.  Flooding can occur with prolonged rainfall over several days, intense rainfall over a short period of time, or when water from an existing source moves too quickly (i.e. snowmelt, dam break, etc.).

Do you know what the flood hazards are in your area? FEMA is revising their maps. Go here to find out if the map of your area has been revised.

Types of flood hazards

More information about these flood hazards can be found on the NWS Flood Safety Website at

Flash flooding

A rapid and extreme flow of high water into a normally dry area, or a rapid water level rise in a stream or creek above a predetermined flood level, beginning within six hours  of the causative event (i.e. intense rainfall, dam failure, ice jam).

River flooding

River flooding occurs when rivers rise and overflow their banks, inundating areas that  are normally dry.

Tropical Systems and Coastal Flooding

Photo of road overwashed by sea

Photo Credit: The Atlantic

At any time of year, a storm from over the ocean can bring heavy precipitation to the U.S. coasts. Whether such a storm is tropical or not, prolonged periods of heavy precipitation can cause freshwater flooding in coastal areas, as well as further inland as the storm  moves onshore. In addition to the freshwater flood threat, tropical systems and nor’easters can bring the threat of storm surge related coastal flooding.

Burn Scars/Debris Flows

Photo of wildfire burning cabins

Photo Credit: NWS

Wildfires burn away the vegetation of an area, leaving behind bare ground that tends to repel water. When rain falls, it runs off a burn scar towards a low lying area, sometimes  carrying branches, soil and other debris along with it. Without vegetation to hold the soil in place, flooding can produce mud and debris flows.


Flooding due to snowmelt most often occurs in the spring when warming temperatures  quickly melt the snow. The water runs off the still partially frozen or already saturated ground into nearby streams and rivers, causing them to rapidly rise and sometimes overflow their banks.

Ice and Debris Jams

A backup of water into surrounding areas can occur when a river or stream is blocked by a build-up of ice or other debris.

Dry Wash

When heavy rain falls over dry land, the water rushes towards low-lying areas, which may include dried up canyon or stream beds. This can quickly turn a dry channel into a raging river.

Dam Break and Levee Failure

A break or failure can occur with little to no warning. Most often they are caused by water overtopping the structure, excessive seepage through the surrounding ground, or a  structural failure.

A sign almost covered by flood water

Photo Credit: Shenandoah Valley Flowers


Understanding the different flood hazards and knowing the actions to take before, during, and afterwards can help you protect your life, the lives of your loved ones, and your property. Prepare now  by visiting



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