Flash Floods: Tips for Driving in Wet Weather

Wet weather alert

Preparing for safety on the road starts before you even leave the house. Wet weather and flooding can hit any part of the country, at any time of year. While the spring thaw and heavy rainfall are common reasons for flooding, hundreds of Canadians are impacted by rogue wet weather conditions, making it one of Canada's most common and costly disasters. Check the forecast before you leave, and stay mindful of heavy rainfall alerts.

When there’s been heavy or steady rain for a prolonged amount of time, it saturates the ground. Once that ground is saturated, water has nowhere to drain, resulting in flooding. To stay safe, make sure your car tires have deep treads – essential for good traction as you travel and, if you can, choose reliable roadways that take you through the higher ground. Low-lying areas – particularly – those near rivers, are prone to flooding in heavy rains.

Getting caught in the rain

The first few drops of rain can impact the road's surface and make it slippery, which means your vehicle's tires will have less contact with the roadway. As more rain falls, the surface becomes increasingly slippery making it difficult to maintain traction. Wet roads can also cause hydroplaning, where the car "rides" on top of the surface, like water skis on a lake. Using tires with a deep tread and driving slowly on wet roads can prevent this, allowing you to maintain control while driving or stopping.

If the weather is particularly bad, roadways may flood. Experts caution drivers that small vehicles may be swept away in only 6 inches of water, while only 18-24 inches is needed to sweep away a truck. Driving through flooded roads carries many risks, as water may impact your braking ability, flood your engine, or irreparably damage your vehicle.

If you drive through high water, the first step is to test your brake pedals' responsiveness. The pedals should be firm when you press them, and the car should stop in a straight line. If the car pulls to the side or the brake pedals feel spongy, you should take your car in for repair immediately.

Stalled in a flood 

Flooding can happen quickly, surprising drivers. If you find yourself stalled out in floodwaters there are a few precautions you can take to protect yourself and your vehicle. When your car stalls, the engine will cut out; don't try to turn it back on, as this will introduce water into your engine, potentially causing permanent damage. Turn on your hazard lights, and if you’re concerned the water level is rising, open the windows and doors to allow for a safe escape route. The priority is to secure the safety of you and your passengers – should water levels continue to rise, leave the car and head to higher ground. 

Once the situation is secure, you can focus on moving your vehicle. The best thing to do, if possible, is to roll, push, or tow your car out of the water and get it to a mechanic. Of course, this should be attempted only under safe conditions. With the car out of the water, disconnect the batteries to prevent further electrical damage. Your mechanic will be able to gauge the height of the flood water relative to vehicle systems, assessing what the flood damaged.

Buyer beware

Ontario's Ministry of Transportation specifically cautions against buying flood-damaged vehicles. Vehicles with irreparable damage from flooding cannot be registered for driving – a great reason to avoid joyriding through puddles.

When buying a used car, work with a certified mechanic to survey it for any water damage. Thoroughly check the vehicle's history before purchase, especially if it comes from an auction or a used car dealer. The engine and systems may be affected, while the car body could have rust and other damage.

Stay alert to stay safe

As we mentioned, flooding can happen quickly. Stay prepared this season by watching the weather forecast, and being mindful of low-lying routes. When in doubt, steer clear of deeper waters as the unknown depth may pose hazardous risks to you and your vehicle. While the rain won’t be forever, the damage could be!