Safety First: Advice for Driving on Wet Roads

The number of breakdowns always increases in the periods of heavy rains as the damp can cause many problems with engines and electrical systems. In addition, driving on wet roads requires an additional dosage of safety to reduce the chances of an accident.

Prepare for driving in wet conditions

Before you head out, consider if your journey is essential or can wait until the rain subsides. Plan your route in advance, avoiding areas which are prone to flooding such as underpasses or neighbourhoods that sit lower than the rest of the urban area. It’s also advisable to let relatives or friends know your planned route and expected time of arrival. Make sure your windshield wipers are fully functional, including both the front and back blades. If you drive an older vehicle, consider updating it with aero wipers, which are more effective at removing water at speed. Remember to top off your fuel tank. Getting stuck in traffic congestion as a result of rain or wet road will increase your fuel consumption. Your fuel economy will be reduced even more by the AC you keep running to prevent windshield from fogging on the inside.

How to drive in the rain

The first rule is to slow down. Since both your stopping time and visibility are reduced, you should leave more distance between you and the car in front. Use dipped headlights so other drivers can see you more easily in the downpour. Rear fog lights, on the other hand, can mask your brake lights and confuse the driver behind you, so keep them off. Be on the lookout for large or fast-moving vehicles that leave a lot of spray behind which reduces visibility. If you happen to break down in torrential rain, remember to keep the bonnet closed while waiting for help. This way, you’re protecting both the electrical circuits and the hot engine block from the direct water. 

Avoid aquaplaning

Driving at speed through standing water could lead to tyres losing contact with the surface, also known as aquaplaning. To reduce the likelihood of aquaplaning, tyres are designed to disperse up to 30 litres of water per second at 80km/h, but with only 1.6 mm tread remaining due to wear, the displacement drops to half of that level. Measurements by tyre manufacturers have determined that tyres with the residual tread depth of 3 mm have just over 80% of their water displacement capability. In other words, when tyres reach the 3mm limit – which is the depth of wet indicators between the grooves, drivers should consider replacing their tyre set. The wet indicators can be found aligned with the raindrop symbol on the tyre sidewall. If your steering feels light out of a sudden – and your car literally starts to glide on the water, ease of the accelerator pedal and allow your speed to drop until you can regain the steering again.

Driving through standing water

Driving through puddles or flooded parts of the road can cause serious damage to your car, not to mention the cost of the repair. When faced with standing water ahead, first estimate the puddle size, even if it means getting out of your car. If the water is muddy, use a stick to gauge its depth. If the puddle is deep for your car, find an alternate route. While modern cars’ door seals are good as watertight, the water might not get inside but make your car buoyant, which means it could start to float. If the puddle is shallow enough for you to drive through, keep with the middle of the road as this way you have fewer chances to avoid holes or objects that could damage your car’s wheels or suspension. Once on the other side, pause for a moment to let the excess water drain before you continue.

Breaking down in the rain

If your engine cuts out after driving through deep water don’t try to restart it as you may cause further damage to it. Instead, turn on the hazard lights, call for assistance and have your car professionally inspected. Flood-related engine damage is usually caused by water being sucked into the engine, causing it to ‘air lock’, which can damage piston connecting rods and valves. In the worst scenario, a new engine will have to be fitted, but good luck demonstrating to your insurance that it was not your action that caused the damage.

While most of us would prefer to stay at home in rainy weather, in reality, we often have to hit the road regardless of the weather conditions. These tips might as well make sure that both you and your car return home safely.