Roadwise States California Driving lessons Hydroplaning, floods, wind, fog & traffic breaks California driving lesson · Safe Driving Fundamentals
Hydroplaning, floods, wind, fog & traffic breaks A 3-minute lesson from the California course. Read the rules and examples, follow the handbook page references, and check your understanding before you move on.
Read time 3 minutes
Course unit Safe Driving Fundamentals
Checkpoint questions 6
Source pages 68, 69, 70 Water, wind and fog each take away something you need: grip, control or visibility. The fix is almost always to slow down smoothly and avoid sudden moves.
Hydroplaning When a vehicle rides on water because the tires lose all contact with the road. A slight turn, braking, or a gust of wind can throw it into a skid.
Handbook p. 68 ↗ To avoid hydroplaning: Drive slowly Steer around standing water, if possible Slow down if you hear sloshing sounds from the tires Slow down when changing lanes or direction Handbook p. 68 ↗ Know the rule
If your vehicle starts to hydroplane, slow down gradually and do not use the brakes; sudden braking may cause you to lose control.
Handbook p. 68 ↗ Dangers of flooded roads: Being swept off the road Floating debris and unseen hazards The road collapsing Vehicle malfunction Electrocution if there are fallen power lines Handbook p. 69 ↗ Know the rule
You may not be able to judge flood depth by looking; find another route. If you must drive through, drive slowly, then test your brakes.
Handbook p. 69 ↗ In high winds (especially trucks, campers, trailers): Reduce your speed Keep a firm grip on the steering wheel Stay alert and watch for debris on the road Do not use cruise control Consider pulling over to wait for the storm to pass Handbook p. 69 ↗ If you must drive in heavy fog or smoke: Drive slowly and use low beams (high beams reflect back and cause glare) Never drive using only parking or fog lights Make sure you can stop within the space you can see ahead; increase following distance Use wipers and defroster as needed Avoid crossing lanes or passing unless absolutely necessary; listen for traffic you can't see If it's too thick, pull off the road, turn on emergency flashers, and wait Handbook p. 70 ↗ Traffic break An officer turns on emergency lights and slowly weaves across lanes to slow or stop traffic, e.g., to remove hazards, in heavy fog, or to prevent collisions.
Handbook p. 70 ↗ During a traffic break: Turn on your emergency flashers to warn other drivers Slowly decrease to the officer's speed; don't brake suddenly unless needed to avoid a collision Keep a safe distance from the patrol vehicle Do not drive past the patrol vehicle or speed up until the officer turns off the lights Handbook p. 70 ↗ Put it into practice
A CHP car ahead turns on its lights and starts weaving across all lanes. Turn on your flashers, slow gradually to match the officer, stay behind the patrol car, and don't speed up until its lights go off.
A useful reminder Fog: low beams, never high beams or parking/fog lights alone.
Check your understanding Read the question, decide on an answer, then open it to check the explanation. These are Roadwise study questions based on the source handbook.
What causes hydroplaning? Tires overheating on dry pavement Excessive tire pressure Water lifts tires off the road Driving on icy pavement Answer: Water lifts tires off the road
Hydroplaning happens when a vehicle rides on water and the tires lose all contact with the road.
Handbook p. 68 ↗ If your vehicle starts to hydroplane, what should you avoid doing? Slowing down gradually Holding the wheel steady Easing off the accelerator Using the brakes Answer: Using the brakes
Do not use the brakes if hydroplaning; sudden braking may cause loss of control.
Handbook p. 68 ↗ In high winds, why should you avoid using cruise control? It uses more fuel in a headwind You need full throttle control in gusts It can overheat the engine It hides your brake lights Answer: You need full throttle control in gusts
Avoid cruise control in high winds so you retain full control of the accelerator if a gust occurs.
Handbook p. 69 ↗ What type of headlights should you use when driving in heavy fog? High-beam headlights Parking lights only Low-beam headlights No headlights, to avoid glare Answer: Low-beam headlights
Use low-beam headlights in fog; high beams reflect back and cause glare.
Handbook p. 70 ↗ If fog becomes too thick to drive safely, what should you do? Continue at the same speed with high beams on Follow another vehicle's taillights closely Stop in your travel lane with flashers off Pull off and turn on flashers Answer: Pull off and turn on flashers
If fog is too thick to drive safely, pull off the road and use emergency flashers while you wait for it to clear.
Handbook p. 70 ↗ Besides being swept off the road, which danger of flooded roads does the handbook list? Brake fade from overheating The road collapsing Sun glare off the water Carbon monoxide buildup Answer: The road collapsing
Flood dangers include being swept away, floating debris, the road collapsing, vehicle malfunction, and electrocution from fallen power lines.
Handbook p. 69 ↗ Previous lesson Slippery roads, rain & snow Next lesson Blowouts, running off the road & stalled on tracks More in Safe Driving Fundamentals About the source Roadwise’s California course uses the driver handbook edition supplied with this study pack. This lesson cites source pages 68, 69, 70. The linked PDF is a third-party mirror of the handbook, rather than a government-hosted page.
Open the handbook source PDF · View the source edition
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