What Is Hydroplaning?

Fight these hydroplaning hazards.

Here's a little pop quiz: Which weather condition accounts for the greatest number of accidents each year?

  • Wet pavement
  • Rain
  • Snow/sleet
  • Icy pavement
  • Snow/slushy pavement
  • Fog

If you guessed wet pavement, you're correct.

Of the 5.8 million accidents each year, 1 in 4 is weather-related. An analysis of National Highway Traffic Administration data found 74% of weather-related crashes occur on wet pavement each year. (That translates to an average of almost 1 million crashes on wet pavement every year.) In an average year, accidents on wet pavement cause 384,032 injuries and 4,789 deaths.

What makes wet pavement so dangerous?

Hydroplaning hazards are among the primary reasons wet pavement is the scene of so many accidents. Hydroplaning occurs when a layer of water accumulates under a vehicle's tires. The tires lift up. The car loses traction. The driver loses control.

Types of Hydroplaning

All hydroplaning is not the same.

  • Imagine walking on a wet marble staircase. Because the surface is smooth, water makes it very slippery. Roadways without microtexture are similar. These roadways are at risk for viscous hydroplaning, where a thin film of water sits atop the roadway, making it impossible for a car's tires to connect with the road surface. If you've ever driven on a roadway that had only a little bit of water on it, yet it was very slippery, you've experienced viscous hydroplaning. This type of hydroplaning can occur at any speed.
  • If you've ever driven in water a bit deeper and felt your car lift off the roadway, you've experienced dynamic hydroplaning. This type of hydroplaning occurs when there is too much water – or too little tire tread – to squeeze the water out from beneath the tire. When this happens, water separates tires from the road. As a driver, this is when you feel a loss of control of the vehicle.

Hydroplaning can occur in as little as 1/10" of water.

Keep Control and Prevent Hydroplaning

Though you may not be able to control the texture of the roads on which you drive, you can control other factors that may cause you to hydroplane. Among the most important:

  • Inflate your tires – This helps ensure tires propel water away from the car.
  • Replace bald tires or tires with thin tread – Tread squeezes water from beneath the tire. Tires that have little tread are less likely to push water out from underneath the tires.
  • Avoid puddles – When water pools, it's more difficult for your tires to do their job.
  • Slow for curves and corners – Rain may collect in low-lying areas, creating hydroplaning hazards.

If you feel your car beginning to hydroplane, resist the urge to slam on your brakes. Instead, turn the car in the direction it is hydroplaning. This will help you maintain control when your tires meet the pavement again.

Follow these tips and show wet pavement that it is no match for careful driving.