Stop Slipping and Sliding: A Guide to Hydroplaning

Imagine you’re driving in the aftermath of a storm, when suddenly you begin to lose control of your vehicle. With concern, you realize you’re cruising on top of standing water instead of connecting to the solid ground.

This is hydroplaning, and it can be panic-inducing for even the most experienced drivers.

To alleviate your worries about hydroplaning, read on to learn what it is, how to avoid it, and what to do if it happens.

What is hydroplaning?

The term “hydroplane” comes from the Greek prefix hydro, meaning “water,” and the Latin noun planus, meaning “flat” or “level.”

Hydroplaning, sometimes called aqua planing, occurs when your vehicle’s tires lose traction on wet roads. When water gets between your tires and the road, your vehicle moves on top of the water instead of making contact with the road. Hydroplaning severely inhibits your ability to brake and steer and can create panic when you feel like your car is out of control. 

What factors affect hydroplaning?

Environmental conditions

• Water depth: Hydroplaning becomes more likely once the water depth is over 1/10th of an inch, meaning hydroplaning risks are higher when the rain is heavier. 
• Lack of drainage: Water tends to pool in wheel spots and ruts, and it may not have anywhere to go without proper access to drains. Clogged storm drains or a lack of drainage infrastructure can lead to more standing water and, consequently, more hydroplaning. 
• Smooth roads: Paved roads with fewer grooves tend to accumulate water on the surface, increasing the likelihood of a vehicle encountering standing water to slide on.
• Low cross-slope: Cross-slope is the side-to-side tilt of a road that helps drain water. Highways use steeper slopes for faster drainage, while pedestrian areas have gentler grades for accessibility. Roads with lower cross-slopes, such as in residential areas, can retain more water and increase the risk of hydroplaning.
• Microtexture: Granular pieces of limestone, granite, and similar materials that contribute to the way a road’s surface looks and feels. Limits hydroplaning by making it easier for tires to grip the road. 
• Macrotexture: Larger bumps and grooves in a road. These can help channel water away, reducing risks of hydroplaning.

Vehicle conditions

• Low tire tread: Deeper, more intricate tire treads effectively direct water away from tires, so better treads lower your risks of hydroplaning. You’ll likely start noticing diminished tire performance when they get below 4/32”, signaling it's time to replace them.
• Worn tires: Due to reduced tread, worn tires are also more likely to hydroplane. Tires with low aspect ratios are short and wide. Their large size leads them to encounter more water at a time, increasing hydroplaning risks. Tires with a higher aspect ratio are taller and narrower and can cut through water more effectively to avoid hydroplaning. 
• Over or underinflated tires: Overinflated and underinflated tires are more likely to lose contact with wet roads, so it's best practice to inflate your tires appropriately. For most passenger vehicles, this means between 30 and 35 psi, but you can check the owner’s manual for details specific to your vehicle. 
• High speed: Hydroplaning also becomes more probable when your car is operating at higher speeds. In fact, cars are more susceptible to hydroplaning when moving at speeds of 35 miles per hour or greater. Manage your speed closely in wet conditions, or you may end up in a scary situation when you start to hydroplane.
• Vehicle weight: Heavier vehicles are also better equipped to avoid hydroplaning because their extra force allows them to slice through water. Combination vehicles, such as pickup trucks or SUVs towing items, are more likely to hydroplane. Their uneven weight distribution impedes the tires’ ability to maintain contact with the road.

How to avoid hydroplaning

While you’ll certainly overcome hydroplaning if it happens, avoiding it altogether is even better.

• Slow down: To reduce your chances of hydroplaning in rainy weather, avoid moving too quickly. When you see standing water, take this as a sign to reduce your speed by 5-10 miles. 
• Avoid cruise control: Cruise control systems sometimes trigger acceleration when they sense a loss of traction, directly defying expert advice not to speed up when hydroplaning. Because your foot is off the pedal when cruise control is on, it can also diminish reaction times.
• Consider a heavier vehicle: Lighter vehicles are more susceptible to hydroplaning because they have less force to exert down on tires and help them grip the road. If hydroplaning is a big concern of yours, you might consider shopping for heavier vehicles.
• Maintain your tires: Proper tire choice and maintenance are essential to prevent hydroplaning. Tires with deeper treads, wider grooves, and directional tread patterns offer improved performance on wet roads, and you can even purchase tires specifically designed for working well in the rain.  

What to do when hydroplaning

If you’re out on wet roads and feel like your vehicle is floating, our advice is not to panic.

1. Do your best to remain calm. 
2. Begin gradually letting up on the gas.
3. Establish contact with the road without slamming on the brakes.
4. Calmly turn the wheel in the direction your vehicle is hydroplaning to align your tires with your movement and speed up the process of regaining control.

When your car is no longer hydroplaning, you’ll notice it’s responding to braking, steering, and acceleration as usual. You can continue on your way at this time, but you may decide to pull over in a safe area to soothe your nerves before resuming your trip.

Drive in rain or shine with Transwest

A good vehicle will make you feel confident behind the wheel, regardless of weather conditions.

To find a car you can trust to get you safely from point A to point B, view our inventory online or stop by a Transwest location today.