It’s a sad fact of life in Britain that we have to put up with more than our fair share of rain, even in summer months.
As well as the general damp, miserableness of it, heavy rain and associated flooding poses a real danger to road users so here are our tips for staying safe when the weather turns against you.
If you know that heavy rain is forecast, expect delays and give yourself more time to complete your journey. Also check your car before you head off to ensure wipers and lights are all in good working order. Pack a drink, phone and some wellies, in case you do get stuck.
Driving in heavy rain
The first thing to do if you’re caught in heavy rain is to slow down and leave more space to the vehicle in front. Stopping distances as much as double in the wet due to a reduction in grip so you need to give yourself more time and space.
Put on your headlights. Heavy rain and spray reduces visibility for all road users. It’s important to put your headlights on not only to aid your vision but also to make your car more visible to other drivers. The Highway Code says you must use your headlights when visibility is less than 100 metres. Be careful about using fog lights, rear fogs can out-shine brake lights due to the glare and reflection from spray.
Be wary of puddles and standing water. What might look like a minor puddle at the side of the road could be hiding a deep pothole or dislodged drain cover that could cause serious damage to your car. Driving through even fairly shallow puddles could also cause aquaplaning, where your tyres’ tread is overwhelmed by the volume of water and they completely lose contact with the road. You’ll feel this as a lightening of the steering.
Driving through flood water
Avoid it if you can.
When faced with a seriously flooded road first check if there’s an alternative way round. Even a long detour is preferable to tackling a dangerously flooded road.
If you have to drive through a flood first check how deep the water is. Get out and check, preferably using a stick to gauge the depth. Remember as little as six inches of flowing water could knock you off your feet, so take care. According to the AA, just a foot of moving water will float a car and two feet of standing water is enough to do the same. It recommends that you shouldn’t try driving through anything more than four inches.
If you’ve determined it’s safe to proceed, take it slowly and stick to the centre of the road. The crown, as it’s known, is the highest point so should be the shallowest section of the flood.
Don’t stop. Maintain a steady slow speed (3-4mph) and don’t change gear. If you need to, slip the clutch to keep revs up and speed down. In an automatic try braking gently while maintaining pressure on the accelerator. Moving slowly will help create a small bow wave which will stop the engine bay flooding. Stopping could flood the engine bay or could allow water to flow into the exhaust pipe - both of which are bad news.
Be aware of other vehicles and pedestrians. You don’t want to soak pedestrians or potentially flood or damage anyone else’s car.
If you do get stuck, it’s usually safest to remain in the car and call for help. Obviously, you need to use your common sense as to whether this is the best option depending on your circumstances.
Once you’re clear of the flood dry your brakes. Apply them gently while driving slowly to remove the water from them.
Remember, modern cars are full of complex electrical systems which are vulnerable to water damage. Rushing through a puddle that forces water into the engine bay or wading into a deep flood could quickly cause expensive damage. Every year the AA rescues almost 9,000 vehicles that have driven through or become stuck in flood water, with an estimated insurance bill of more than £34 million.