In a fight between your vehicle and water,
your vehicle (and you) will lose.
Boulder, Colorado has been getting an insane amount of rain, and many roads are flooded, so I thought I’d talk about the deceptive dangers of driving though water.
If you’re driving and you see that the road ahead is flooded, you have a choice. Should you continue driving through it? You may drive on this road every day, and you’ve been fine. You may have driven on this road just a little while ago, and the road was dry, and you were fine.
But here’s the problem, and it has to do with that pesky little thing called physics.
Water, as you know, is slippery. If you’re driving quickly, just a thin film of water on the road can cause you to lose control of your car. That’s why you should slow down in the rain. (Because water reduces friction.)
But hey, you’re going to drive slowly through this water, so what could happen?
Well, that water could be moving faster than you realize. And even if it’s only six inches of water, and just barely touching your hubcaps, you can lose control of your car. (Physics again: If the water is moving at 8 miles per hour, the water is exerting a force of 264 pounds on every square foot where it touches your car.)
So what if you barrel through it, creating a huge splash? (And I have to admit, I’ve done this in big puddles, and it’s fun). Won’t the force of a fast-moving vehicle help you?
Well, the faster you zoom through a big puddle, the less time your car tires are actually touching the road, and so it’s even more likely you’ll lose control of your car.
Then there’s the pesky problem of not knowing how much water you’re driving through. What if it’s deeper than you think? It only takes between 12 and 24 inches of water to make your car into a boat. Boats float away. And your car is not equipped to navigate through water like a boat.
It also doesn’t matter if your car is actually a truck, and it’s very heavy. Battleships weigh thousands of tons, and they still float.
And more importantly, another science tells us why it’s a bad idea to drive through water. Statistics tell us that more people are killed in flash floods than in any other type of bad weather, and that most of the people killed were driving in their cars.
– Photo source: Daryl Orr, Twitter>>
– Lots of flood physics in a PowerPoint presentation by Steve Waters>>
– Floods, FEMA>>