Hydroplaning on I-25 With a Tailgater and a Deer
You are northbound on I-25 near Castle Rock at 65 mph. A light rain has just begun after a dry week, and the pavement looks glossy. Your tires have about 4/32 inch of tread left. A pickup truck is following about one and a half car lengths behind. Ahead, water is pooling in the left lane, and a deer is standing on the right shoulder, head up, facing the road. Your exit is one mile ahead. You are in the middle lane with a clear lane to your right, but a semi is about 200 feet back in that lane. The defroster is on, and your wipers are on intermittent. You feel the steering get light for a moment as you cross a patch of water.
1. What following distance do you need in this rain, and what should you do about the pickup tailgating you?
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In rain you need more than the normal three-second gap-at least four seconds, and more if visibility is poor or water is pooling. At 65 mph, four seconds is about 380 feet. The pickup at one and a half car lengths is far too close, but you cannot fix that by slamming your brakes. Instead, open space ahead of you: slow gradually, signal early, and move to the right lane only after checking that the semi 200 feet back is not already arriving. Do not brake-check. If the pickup stays glued to you, let it go around when possible and keep your own escape space.
2. The steering suddenly feels light as you cross the water. What is happening, and what should you do?
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The light steering means the tires have lost contact with the pavement and are riding on water-hydroplaning. Do not jerk the wheel and do not brake hard, because either can cause a spin once the tires regain grip. Ease off the accelerator, hold the wheel straight, and let the vehicle slow naturally. Avoid cruise control. Once you feel the tires reconnect, reduce speed and stay out of the pooled water in the left lane. Your 4/32-inch tread is not helping; it is near the point where wet traction drops sharply, so treat the rest of the drive as a low-speed, high-gap trip.
3. The deer is on the right shoulder, and you are considering a lane change to the right. How do you manage both hazards?
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The deer is a reason to slow and cover the brake, not to swerve into the semi. A sudden swerve at 65 mph can cause a loss-of-control crash or put you into the lane the semi is using. Reduce speed smoothly, watch the deer's head and shoulders for movement, and be ready to stop if it steps out. For the lane change, signal before you move and wait until the right lane is clearly open; do not cut in front of the semi. If the deer stays on the shoulder and the right lane is blocked, stay in the middle lane at a reduced speed until the semi passes and you have a safe gap.