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Flash Floods

A flash flood is one that rises and falls rapidly with little or no advance warning. Flash Flooding occurs when the ground becomes saturated with water that has fallen too quickly to be absorbed. Ice jams on rivers can be in a winter or spring thaw, a dam can give way, or heavy rains and thunderstorms can quickly fill dry streams and river beds. Any of these causing treacherous overflow where the runoff collects in low-lying areas and rapidly flows downhill.

With it’s momentum, flash floods can carry with them debris piles, logs, even boulders and trees, destroying anything in the waters path. Flash floods develop quickly and sometimes without visible signs of rain. They can originate from many miles away, water levels rising within seconds. Six inches of fast-moving flood water can knock you off your feet; as little as two feet of water can relocate an SUV-sized vehicle.

Never try to walk, swim or drive through such water momentum. Seek higher ground immediately (if in a vehicle, get out and leave it). You may only have seconds to act and climb to .


Know your flood risk and elevation above flood stage.
Get out of areas subject to flooding. This includes dips, low spots, canyons, washes, etc.
Know your evacuation routes.
Any deterioration in wheather conditions.
Build up of clouds or sounds of thunder.
Listen for thunder. Runoff from a faraway thunderstorm could be headed your way.
Watch for signs of possible flash flooding such as sudden changes in water clarity (clear to muddy)
Watch for rising water levels or strong currents.
An increasing roar of water up-canyon.
Be especially cautious at night when it’s harder to recognize flood dangers.