The physics behind the power of flash flooding

The physics behind the power of flash flooding

Footage of recent flash flooding events along Highway 24 shows vehicles being swept down the road as if they weigh nothing.

According to a UCCS professor of physics, Tom Christensen, water has two effects on objects in its path: lifting and pushing.

Christensen said 2 feet of water is enough to float an object weighing around 3,000 pounds.

"It's not a problem for 2 feet of water to float a car right off the ground," he said.

The momentum of flowing water can also exude a large amount of force on stationary objects.  For example, a gentle stream will exert a force of 500 pounds against the side of a car while the force of a rushing flash flood can reach upwards of 1,000 pounds.

"Think about how much weight that is. There is no way that you're going to resist it," said Christensen.

Combine these two factors, and scenes such as those where cars are floating down the highway ensue.

Because of this force, drivers are warned to stay in their car if caught in a flash flood.

"It can hit you with enough force to knock you over and once it knocks you over, and you're floating, you'll weigh a lot less.  So, it will push you wherever it wants to push you," said Christensen.

David Hunting, public information officer of Manitou Springs Volunteer Fire Department, said it is advised for drivers to stay in their vehicles with their seat belts fastened until first responders are able to intervene or until flood waters recede. 

He said it is also very important for everyone to keep an eye on the weather, as to not be caught off-guard and in the line of danger.

comments powered by Disqus

Must See Videos

  • Slap Me Some Skin
  • WATCH: Meet three of the pilots of the U.S. Air Force Thunderbirds
  • Pueblo West vs. Valor Christian