HydroplaningNew Zealand

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202. Hydroplaning

Hydroplaning, also called aquaplaning, occurs when a layer of water builds up between a vehicle’s tyres and the road surface, causing the tyres to lose contact with the road. Steering, braking and acceleration can then become much less effective. The risk increases with speed, standing water and worn tyres. Drivers should reduce speed in heavy rain, avoid sudden steering or braking and make sure their tyres are in good condition with sufficient tread depth.

What is hydroplaning?

Hydroplaning occurs when water separates the tyres from the road surface, reducing or temporarily removing normal tyre grip.

What causes hydroplaning?

The risk increases with higher speed, standing water, worn tyres and insufficient tyre tread. Tyre pressure and road conditions can also affect the risk.

How can you reduce the risk of hydroplaning?

Reduce speed in heavy rain, avoid driving through deep standing water where possible and keep your tyres properly maintained with sufficient tread depth.

What should you do if your vehicle starts hydroplaning?

Remain calm, ease off the accelerator and avoid sudden braking or steering. Keep the steering movements smooth and controlled until the tyres regain contact with the road.

Can worn tyres increase the risk of hydroplaning?

Yes. Tyre grooves help move water away from the contact area. Worn tyres can remove less water, increasing the risk of losing grip on a wet road.

At what speed does hydroplaning occur?

There is no single speed at which hydroplaning always begins. The risk depends on speed, water depth, tyre condition, tyre pressure and the road surface.

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