Every few weeks, we see an online video of yet another Tesla pushing through deep flood water somewhere. The below tweet has one that’s about the deepest I’ve seen, with the water going onto the Tesla’s windshield, and that still didn’t stop it from passing through the floodwaters. In this article, I want to talk a bit about why EVs are able to get away with this, why it’s still a bad idea, and one possible future exception.
— Tesla Owners of Silicon Valley (@teslaownersSV) August 18, 2021
Why ICE Struggles To Deal With Water
Driving in deep, deep water has long been a “holy grail” of sorts, especially in the off-roading scene. Many people around my age got introduced to this idea by the 1997 film Dante’s Peak, where a massive volcanic eruption leaves a town cut off from the rest of the world by collapsing infrastructure, leaving a river crossing as the only option to escape certain doom. James Bond and Sarah Connor (well, not those characters, exactly, but the actors who played them) get in a specially-equipped Chevrolet Suburban with a “snorkel” that allows the engine’s intake to get air even when most of the vehicle is underwater.
On top of needing a snorkel to get air for combustion, if you wanted to build a 1987 Suburban that could do what the one in Dante’s Peak did, you’d have to get one with a 6.2L or 6.5L diesel engine (both of which kind of sucked in stock form). Why? Because a gasoline engine’s spark plugs, distributor cap/rotor (or, later, the electronic ignition components), and other spark plug bits would get shorted out if you submerged the engine, stopping the vehicle dead in its tracks.
Even then, you’d run into problems if the snorkel got too much water in it or worse, got submerged itself.
That hasn’t stopped people from doing crazy, crazy things to get ICE vehicles to work deep under the surface. The most extreme example is when some Australians rigged up a truck to drive across the bottom of Darwin Harbor. They didn’t make it across the full 7 kilometers, but still manged to get more than halfway across using a system of long, flexible pipes attached to small boats that kept the intake and exhaust of the truck above the surf.
Electric vehicles don’t have the life support requirements that ICE engines do, though. With no intake, no exhaust, no spark plugs, and no fuel system, there’s very little that can go wrong. The big wires leading from a sealed battery pack to a sealed drive unit already have to have waterproof connectors to safely operate in rain, so you’re not going to be able to short those systems out very easily at all.
That’s why you see videos like the one toward the beginning of this article. An EV can get into pretty deep water before it would actually create problems for the vehicle’s drive systems, so people sometimes take the opportunity to drive right through deep water that sometimes collects on roadways.
Stalled Engines Aren’t The Only Risk, Though
Just because you can get through deep water without killing the car doesn’t make doing that a good idea.
First off, you don’t know what you can’t see under the water. Even if you’ve been on the road a thousand times, it’s possible that the flood waters have messed things up. The road’s surface might have been eaten away by fast-moving water (which we’ll get to more in a minute), debris that the car can hang up on could have washed up, or something else can be really wrong with the road. You could suddenly get surprised halfway across and be stuck in deep water, which will eventually seep into the car and destroy it.
Worse case, you fall into a deep hole or rut and get completely submerged and trapped, but something much worse could quickly kill you if you drive through water.
The most dangerous problem is that it doesn’t take much fast-moving water to wash a car completely off the road. Sure, your EV doesn’t have an engine that can stall, and it’s heavy, so it’s more likely to stay planted, but even a relatively slow flow can exert tons of force on the side of your vehicle. If the water is moving at all, it could push your car right off the side of the road and send it downstream, where it could be battered until both it and everything inside of it gets destroyed.
In one canyon near Monticello, New Mexico, there used to be a really neat publicly-accessible 4-wheel-drive trail.
So, in reality, driving through deep water simply isn’t a good idea, no matter what kind of car you’re driving. Flood waters usually subside after a few minutes or hours, but you’re gambling with losing the rest of your life just to save a little time today. It’s just not worth it.
As the signs say, “Turn Around, Don’t Drown.”
One Exception To This Rule
The screenshot from a Jeep video at the top of this article (which comes from the end of this video) shows a future electric Jeep driving at the bottom of a river or lake. Jeep didn’t actually film a Jeep going underwater, and a disclaimer says “Fictionalization. Do Not Attempt.” But the idea isn’t too far-fetched. Jeeps are actually designed to handle a certain depth of water before they’d take any damage, with no expectation of damage at depths of up to 30 inches.
Even then, you need to know the trail, know what the depth really is (there could be an unexpected hole), and build up experience over time. You wouldn’t want to take a vehicle built for water fording out to its maximum depth if you have no experience driving off-road or in water. It may be good to get training at an off-road school if you don’t have any experienced people to teach you the ins and outs of doing it safely.
It’s possible that Jeep and other manufacturers may build entirely waterproof electric vehicles at some point in the future, too. Nobody has announced any solid plans, but Jeep’s CEO did discuss it further recently. “There is a little wink we have at the end, which is probably post-2030, but I know a lot of enthusiasts and a lot of our communities are requesting it,” CEO Christian Meunier told The Detroit News. “There are some crazy, very amazing people in the Jeep community who do that type of thing already with an ICE, so you can imagine with a battery car what it would be.
Yes. It will even float for a while.
— Elon Musk (@elonmusk) April 20, 2020
Elon Musk has also discussed the idea of Teslas in water, but specifics of what kind of water fording depths it can handle have yet to be released.
Featured image: Screenshot from Jeep’s “Life Electrified – 80 Years” Video, showing an electric Jeep Wrangler driving at the bottom of a deep body of water, with a fish passing in front of the camera.