Night lane shift with old markings still visible
At 11:30 p.m., you are driving a pickup towing a 16-foot boat on a Missouri interstate. Ahead is a work zone. An orange sign reads 'LANE SHIFT 1/2 MILE'; another reads 'SPEED LIMIT 45.' A flashing arrow board points traffic to the right. The right lane is closed. Temporary white edge lines shift traffic onto the right shoulder area; old yellow and white lines are still visible under portable lights. A flagger at the far end of the shift is holding a STOP paddle facing your direction. Workers and equipment are behind barriers. Traffic is light, but a semi is 200 feet ahead in the shifted lane. You are traveling 65 mph. The temporary lane is about 11 feet wide, and the pavement is uneven at the shift.
1. What speed and following distance should you choose before the shift?
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Begin slowing as soon as you see the orange 'LANE SHIFT' sign and the arrow board. The 'SPEED LIMIT 45' sign is regulatory in the work zone, so 65 mph is too fast; reduce to 45 mph or lower before you reach the shift. A lower speed is justified by the narrow 11-foot temporary lane, the uneven pavement, the night visibility, and the boat trailer. Increase following distance well beyond the normal gap: the semi ahead is only 200 feet away at highway speed, which is too close for a trailer in a work zone. Aim for at least four seconds or more, and do not close the gap when the semi slows. Brake gently before the uneven pavement rather than while turning into the shift.
2. Which markings and devices control your path through the zone?
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The orange signs, the flashing arrow board, the temporary white edge lines, and the flagger control the path. Temporary markings in an active work zone take precedence over the old yellow and white lines that remain visible. Follow the arrow board to the right and stay inside the temporary lane; do not drift back toward the old lane lines or use the closed right lane. When you reach the flagger with the STOP paddle, stop and wait for a signal to proceed, even though traffic is light and no workers may be visible in your immediate path. If the old markings conflict with the temporary ones, treat the temporary devices and flagger as the current information. Do not cross behind barriers or into the closed area.
3. The semi ahead straddles the temporary lane. What should you do?
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Do not pass the semi in the work zone or squeeze alongside it on the shoulder. A wide vehicle may need the full temporary lane or may be positioned to avoid equipment or uneven pavement; passing would put your boat trailer into a narrowing space with little margin. Slow further, increase the gap, and let the semi clear the shift before you enter it. If the semi stops, stop behind it at a safe distance rather than steering around it into the closed area or behind the barriers. The flagger's STOP paddle reinforces that you should wait. Once the lane opens and the flagger releases traffic, proceed at a speed that lets you keep the trailer inside the temporary lines.