Most of us have heard of flash floods on the news, in books, or on the internet. However, few have experienced this force of nature up close, so it's easy to underestimate its sheer speed. During a flash flood, a wall of fast-moving water can sweep through a low-lying canyon or riverbed, washing away trees, boulders, and anything else in its path.
Flash floods can also strike areas where the weather is clear and dry, due to heavy rainfall miles upstream. By the time you hear or see it coming, you may have only seconds to get out of its way and escape to higher ground. If a flash flood strikes your campsite in the middle of the night, you'll have even less time to react. According to the National Weather Service (NWS), a 6-inch-deep creek can swell into 10-foot raging rapids in less than one hour.
The power of flash floods is also easy to underestimate. Only 6 inches of fast-flowing water can knock a strong adult off his or her feet, and 2 feet can carry away a large truck or SUV. Water may not even reach the top of your car's tire, but it can still push it off the road. The Centers for Disease Control and Prevention report that over half of all flood-related drownings occur when a vehicle is driven into hazardous flood water. This is why the NWS slogan “turn around, don't drown” was developed.
In order to document the speed and power of flash floods, one videographer has become a flood-chaser of sorts. His name is David Rankin, and he has a YouTube channel dedicated to films of flash floods. The video below has received nearly 3 million views, and shows an up-close look at the debris-laden floodwater front. Warning: Some of the actions seen in this video are extremely dangerous. Do not attempt to get this close to a flash flood.
In a more recent video from August 2016, Rankin shows the terrifying progression of floodwater through narrow canyons and riverbeds in Utah. He states that these floods occurred over 6 hours after the storm had passed through the region. Again, even if the skies are clear, it's important to be extremely cautious when traversing low-lying areas. Rankin's recommendation is sound: check weather forecasts thoroughly before visiting flood-prone canyons.
Finally, we'll leave you with a legitimately scary cell phone video taken of a flash flood. This group of hikers, including several children, entered one of Utah's most famous slot canyons on a clear day. The video description states, “We checked the weather the day prior and there was no chance of rain. We were out of cell phone/internet coverage. This is proof of how fast things can get ugly!”
The takeaway from these videos should be obvious: be extremely careful around low canyons, riverbeds, and dry lakebeds. A flash flood can sweep through in minutes, and push you downstream with immense force. Check the forecast, be aware of your surroundings, and watch for signs of rainfall in the distance.