I have recently been swamped with questions on how deep a vehicle, whether it is four-wheel drive or not, can go thru flooded streets – thanks to recent rains of biblical proportions that have contributed to massive traffic jams because of floods. Having seen photos of those traffic jams in social media, I wonder if those taking the pictures noticed that despite the huge amount of water on the streets, the floods are not really that deep. If they look closely, they would have noticed that in most cases the floods are only up to a child’s knees. My best estimate is the depth is from six to 12 inches, thus making flood crossing very manageable even for the lowest of the lowered “rice rocket” out there.
My point in all of this is in most but not all cases, flooding where the water is usually gutter-deep level, most if not all vehicles can manage to drive thru and avoid creating massive traffic jams.
So here is a compilation of what to remember when crossing flooded streets.
• Look around and asses the situation, like what I said of floods just being gutter level;
• A safe estimate of your vehicle’s wading depth is half the diameter of the wheel. So if water is only half of your wheel diameter, you can drive your vehicle thru the flooded street with minimal effort;
• One has to remember water is heavy or a cubic meter of water can weigh a ton! So if your vehicle must cross a flooded street, make sure is has enough power or torque to move a couple of tons of water. That will also depend on how big the front end of your vehicle is. If you don’t understand what I am saying, then you have no business crossing flooded streets;
• Most new vehicles are well sealed that in moderate water depth or just above the bottom of the door line, water will not seep into the car’s cabin;
• Once you have started to cross a flooded street, do not hesitate and stop. Maintain a slow constant forward motion. This prevents your vehicle from floating and loosing traction;
• Be aware of vehicles ahead of you that are also crossing a flooded street. See how high the water reaches the vehicle in front of you;
• If you drive a vehicle with manual transmission, stay off the clutch pedal when crossing a flooded street;
• It is safe to assume that main thoroughfares have no potholes deep enough to get you stuck. It is safe to assume that if the water is not that deep, you and your vehicle won’t fall into one and get stuck. So keep moving to avoid starting a traffic jam;
• Know where your vehicle’s air intake is located because that way, you know the limit of your vehicles water-wading capacity.
• When in doubt, don’t be a traffic jam starter. So find a way to get off the street and let other vehicles pass thru. A few seconds of hesitation is enough to start a traffic jam several hundred meters long on busy streets;
• Because flooded streets are full of debris of all sorts, park your vehicle in a clear space after crossing and make sure the grill of your vehicle is not blocked because that can cause overheating;
• If your vehicle has a 4WD system with a low range gear in the transfer case, engage to 4WD low to maximize its ability to push water; and
• Do not use 4WD high when crossing. This actually lessens your engine power by half because your engine is driving two axles instead of one and this will probably cause you to stall in deep water.
Although vehicles can cross flooded streets if the abovementioned are followed, it is still best to wait for the rains to stop and floods to subside in a coffee shop or some other place where you have access to some comforts and toilets. That is actually better than getting stuck in your vehicle and contemplating what time you will get home while holding back the “call of nature.”