Caltrans, California's State Department of Transportation, posted a video to their Facebook account on August 29 that perfectly illustrated the utility of these ramps. The video, shot by a traffic camera on I-5 northbound near the Grapevine, showed traffic moving along smartly when suddenly a white tractor trailer barreled into the median escape ramp. The truck hit the ramp at a high rate of speed out of a broad, right-hand curve in the freeway and immediately dug into the deep gravel. The truck continued up the ramp and, although it looked like it might jackknife once or twice, it eventually came to a safe and upright stop in a thick cloud of gravel dust.
Truck arrestor ramps are a common site along mountain highways. They are typically long, straight, gravel-filled ramps along downhill stretches designed to help truckers stop runaway trucks safely. Lose your brakes coming down a long grade? Got nowhere to go but off a cliff or into a column of traffic? The runaway ramp is there for you. It's a last resort, sure, and it might end your driving career, but coming in hot to a runaway ramp and walking away unemployed is way better than a fiery crash and possible death.