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Know Your Flood Risk
Flooding is one of Fairfax County’s most common hazards. Be prepared for flooding no matter where you live, but particularly if you are in a low-lying area, near a body of water, or in other areas known to flood in previous storms. The first step is understanding your flood risk.
A floodplain is the flat area next to the main stream channel. When stream banks overflow during or after a storm, the floodplain provides natural storage for the excess water.
Sumps are depressions or bowls where there is not sufficient drainage for the water to get out of the depression.
The path the water takes to get to sumps or floodplains is called the overland relief path.
Special Flood Hazard Areas
Special Flood Hazard Areas (SFHA) are high risk areas that have a one-percent chance or more of being inundated by a base flood in any given year as identified by the National Flood Insurance Program maps. Floodplain management regulations must be enforced and mandatory purchase of flood insurance applies for these areas. Visit:
FEMA - Know Your Flood Risk
Residents can help protect their property from the effects of flooding by understanding the risk in their area and possible actions. Visit: