Mountain Flash Flood Safety

Streams in and on the edge of the Colorado Rockies are vulnerable to extreme flash flooding. Flooding can ensue quickly when intense thunderstorms produce heavy rainfall in the mountains. The steep mountain slopes and narrow canyons funnel the storm runoff into small creeks and dry ravines; turning them into raging torrents of water. Flash flood waves, moving at incredible speeds, can roll boulders, tear out trees, destroy buildings, and bridges, and scour out new channels. Walls of water can reach heights of 10 to 20 feet.

Additional Flash Flood Safety Tips in or near the Mountains

  • Climb to safety! If a flash flood is catching you during a hike or in camp, climb to higher ground as fast as you can.


  • Stay away from streambeds, and other drainage channels during and after rainstorms or when heavy rain is possible. If you are by a stream and the water begins rising rapidly, treat the situation as a flash flood. Mountain streams can rise several feet or more in just a few minutes.


  • Do not camp along streams and washes, particularly during threatening conditions. A flash flood can catch you while you are sleeping. Locate your camp on ground that is significantly higher than the stream or canyon.


  • Stay tuned to what the weather is doing upstream. Rain upstream, perhaps many miles away, can roar down a canyon and catch you completely by surprise.


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