Stopping Distance
As you develop your skills during your driving lessons in Basingstoke, you will find that wet roads reduce tyre grip, so slow down. Give yourself plenty of time and room for slowing down and stopping. Keep well back from other vehicles.
On a wet road, you should allow at least double the stopping distance for a dry road.
After a spell of dry weather, rain on the road can make the surface even more slippery. Take extra care, especially when cornering.
Be aware that different road surfaces might affect the grip of your tyres.
Remember, the less tread on your tyres, the greater the increase in breaking distance.
Consider others: Pedestrians and cyclists can easily get drenched by passing vehicles. Look well ahead and show consideration by slowing down or giving them more room when it is safe to do so. Also give cyclists room to pull out to avoid large puddles.
Aquaplaning
A great danger when driving at speed in very wet weather is the build up of water between the tyre and the road surface. As a result your vehicle actually slides forwards on a thin film of water as your tyres lose contact with the road surface. Even good tyres cannot grip in this situation. It is called aquaplaning.
A clear indication that you are aquaplaning can be that the steering suddenly feels very light.
When this happens slow down by easing off the accelerator. Never brake or try to change direction, because when you are aquaplaning, you've no control at all over steering or braking.
The higher speed on a wet road, the more likely you are to aquaplane. You must keep your speed down and watch for water pooling on the road surface.
Even at lower speeds, if the front and rear tyres on one side of the vehicle hit a patch of deeper water, the vehicle may swerve because of the additional resistance on that side.
Spray
Another reason for keeping your speed down on wet roads is the amount of water thrown up by other vehicles.
Overtaking or being overtaken by heavy vehicles on a motorway can be an unnerving experience.
If necessary, slow down to increase the distance between you and the large vehicle, remembering to look in your mirrors before you do so.
Sometimes, even working at full speed, wipers can't keep the windscreen clear. This results in the driver being temporarily blinded to conditions ahead, you may need to slow down.
If water sprays up under the bonnet, it can stop the engine or affect electronic controls.
Dealing with floods
When you have to pass through a flood, take your time.
Stop and assess how deep the water is. Don't just drive into it.
Sometimes roads likely to flood have depth gauges. Check the depth on these.
Deep water: If the water seems too deep for your vehicle, turn back and go around the flood by another road. It might take a little longer, but that's better than finding yourself stranded.
If water is too deep it could:
Flood the exhaust causing the engine to stop
Find its way into the air intake on some vehicles, causing serious engine damage.
Shallow water: If the water is not too deep, drive on slowly but be sure to keep to the shallowest part. Remember, because of the camber of the road, the water is probably deepest near the kerb and shallowest at the crown.
Driving through floodwater: Drive in first gear as slowly as possible but keep the engine speed high and steady by slipping the clutch:
If the engine speed is too low, you might stall
If you go too fast, you could create a bow wave. Water will flood the engine and it could cut out.
Engines and water: Some types of diesel engine will tolerate a certain amount of water, but many modern fuel systems are electronically controlled and are, therefore, affected by water.
All petrol engines can be seriously affected by even small amounts of water being splashed onto the electronic components, such as engine management systems, coil distributor, leads and so on.
Crossing a ford
The depth of water at a ford varies with the weather and is usually greater in winter.
There may even be a depth gauge.
If the water is not too deep for your vehicle, cross using the same technique as you would for a flood.
Remember to test your brakes after you cross. There might be a notice reminding you to do so.
Don't try to displace the water by 'charging' at the ford or flood.
You could lose control
Your vehicle will probably stall
You could end up blocking the road.
Test your brakes
Water can reduce the effectiveness of your brakes, so test your brakes when you have passed through water on the road.
When you've driven safely through, check your mirrors first and then test your brakes.
If they do not work properly, it will help to dry them out if you apply light pressure to the brake pedal while driving along slowly. Do not drive at normal speed until you are sure they are working normally.