District of Columbia driving lesson · Weather & Emergency Situations
Wet roads, hydroplaning & flooding
A 3-minute lesson from the District of Columbia course. Read the rules and examples, follow the handbook page references, and check your understanding before you move on.
Wet pavement is far more slippery than dry. It's harder to hold the road on curves and it takes longer to stop. Deep or moving water is worse: it can float or carry off your vehicle.
Know the rule
Be especially careful at the beginning of a light rain. The mixture of oil and water on the pavement is particularly dangerous until a rain of several hours washes the oils away.
Flash floods can come rapidly and unexpectedly, within a few minutes or hours of excessive rainfall. Do not drive through flooded areas; turn around and find another route. Be especially cautious at night.
Even if the water looks shallow, do not try to cross a flooded road. Water can hide dips, and floodwaters can wash away the road surface. If there's no other route, go to higher ground and wait for the water to go down.
It starts drizzling after a dry week. This is the most slippery moment, as oil and water mix on the pavement. Slow down and leave extra space. If the car starts to float, ease off the gas and steer straight. Don't brake hard.
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.
When is wet pavement most dangerous, according to the handbook?
After several hours of steady rain
At the start of a light rain
Only during a heavy downpour
Once puddles have formed
Answer: At the start of a light rain
Early light rain mixes with oil residue on the road, making it especially slippery before it washes away.