What it is
Hydroplaning occurs when built-up water on roadways is not sufficiently pushed out of the way by your vehicle’s tires when going at a regular or high speed. The water then causes your vehicle to rise and slide on top of a thin layer of water between your tires and the road. All traction is lost in less than a second and you have very limited control of your vehicle.
There is no precise equation to determine the speed at which a vehicle will hydroplane. In general, cars hydroplane at speeds above 45 MPH , where water ponds to a depth of at least 0.10 inches over a distance of 30 feet or more.
What to do if it happens
If you find yourself hydroplaning, stay calm. Don’t brake or turn suddenly. Ease your foot off the gas, and hold the wheel firmly. Do not steer in any direction other than straight. If you do need to brake — and don’t have anti-lock brakes — do so gently with a pumping action.
How to prevent it
Drive slowly and carefully: When it’s raining or there is water on the road take your time around curves and steer and brake with smooth, light touches. Most of America’s roads are crowned, meaning water will run to the sides and puddles will accumulate. So, keep towards the middle of the road and drive in the tire tracks left by cars in front of you.
Be extra cautious at intersections: This is a common location where engine oil and water mix, creating extremely slick spots.
Check your tires: Worn tires will hydroplane more easily for lack of tread depth. Underinflation can cause a tire to deflect inward, raising the tire center and preventing the tread from clearing water. Tires that present the greatest risk are small in diameter and wide.
Add weight: More weight on a properly inflated tire lengthens the contact patch, improving its aspect ratio. This is more important for vehicles hauling unloaded trailers and empty pickup trucks with uneven weight distribution. Caution – weight can actually have the opposite effect if the tire is underinflated.
Avoid using cruise control: There is a chance that your car will accelerate if you hydroplane, and your reaction time will be slower if using cruise control.
Let us know if you have any questions, comments or experiences about hydroplaning below.