What is water wading depth and why does it matter?

We go on and on about horsepower and torque when talking about cars, but there is one metric that is arguably just as important as the rest especially if you live in the Philippines in a flood-prone area, and that is water-wading depth. 

In layman’s terms, water wading depth is the measurement stated by the vehicle manufacturer that is the deepest that your car can go through a body of water, be it a flood or a river. 

However, there are other factors that determine this and the assumption is that you will be “wading” through the water with your vehicle and not sitting still. It’s important to remember that water wading depth is not a static measurement, rather, it is assumed that you will be wading for a few minutes. Typically, most cars will be able to wade water as deep as the top of their front wheels, but other vehicles like the Ford Everest and Ranger or the Isuzu D-MAX boast a depth higher than that, about 800 mm. As such, it’s best to consult your owner’s manual or research your manufacturer’s rated depth before you make any assumptions. 

Things like your vehicle ride height, the location of your engine, air intake, fuse box, battery, and other water-sensitive components will make up the bulk of your concerns when it comes to water wading. As a general rule of thumb, you don’t want air and water to mix on the way to your engine’s combustion chamber or its other fluid reservoirs, and you don’t want water to short-circuit your vehicle’s sensitive electronics, though that is not all too common. 

Related but unrelated is cabin water intrusion. If you wade through floods and water is finding its way into your car’s interior, then perhaps that is a sign that your weather seals are worn out or getting overwhelmed by the amount of water trying to get in. With that being said, if water does find its way into your cabin, your vehicle may come with drain holes that you can use in order to flush it out. 

Since water wading depth is dependent on the exposure of certain components, you can take several steps to ensure that these components are high and dry—literally. If you want some inspiration, then look no further than the off-road community. These guys know a thing or two about crossing a flood, or even a river. The art of water wading is about technique, but that doesn’t mean that preparations can be made in order to ensure that your car gets wet safely. 

Lift - If depth is a concern, then raising your vehicle’s ride height can help keep your battery, air intake, and even the cabin away from water intrusion. Increasing the vehicle height can also increase ground clearance, which is a metric that off-road vehicles crave when attacking trails. This is perhaps one of the very first things that off-roaders do for an all-around improvement in off-road handling. 

Snorkel and other breathing tubes - Good technique will keep water out of your engine bay, but even then there is no assurance that the air intake won’t take in at least some water especially when things get a little too deep. As such, a snorkel will give you more clearance and peace of mind when tackling water crossings or wadings. On top of that, you might want to consider upgraded breather tubes in order to keep your engine running smoothly and to help prevent water from mixing inside your engine. 

Of course, these upgrades only apply if your car has an aftermarket of parts to feed off of. 

Most cars are capable of wading through some amount of water, but just because it doesn’t have a figure doesn’t mean that they can’t soldier through. The key is to gauge the depth before you commit and assess the risk properly before deciding to go through, using the wheels as a gauge is a good rule of thumb, but even then you’re putting yourself and your car at risk should you get stuck. 

As for other items like your vehicle's electronics, as long as your battery, alternator, fuse box, or ECU gets submerged for long periods of time under water, you you should come out fine. Just remember that prolonged exposure to water could damage these components and that they're usually the first to go if ever a car gets flooded. 

Water wading is also not an indicator of how resistant a vehicle is to flooding. Remember that water wading metrics are not static ratings, which assumes that you will be exposing your vehicle to water for a short duration, and not for prolonged periods. 

In general, crossovers, SUVs, pickup trucks, MPVs, and even vans will be more capable compared to sedans and hatchbacks when dealing with water wading, with SUVs and pickups being the ideal choice.