This issue of ITE Journal is dedicated to speed management—arguably the largest issue faced by our membership. What unites us all is an emphasis on safer outcomes for those we serve. Eliminating roadway fatalities and serious injuries is the vision, and that means protecting vulnerable road users. The increase in fatalities among pedestrians and cyclists in the United States over the last 15 years has been alarming (Australia, Canada, and New Zealand have managed to hold their numbers constant over the same period). Interestingly, the rate of pedestrians and cyclists killed or injured in the United States hasn’t changed and even went way down during COVID. The percentage of fatalities among vulnerable road users went up! The culprit is kinetic energy: 0.5 mass × velocity squared. Heavier vehicles played a part, but speeds played a larger one. Our members have been actively engaged in traffic calming for nearly 40 years. Traffic-calming technical details remain the most viewed portion of www.ite.org. We are dealing with the legacy of designing roadways for 5–10 miles per hour (mph) (roughly 10–15 kilometers per hour [kph]) over the intended speed limit of facilities, and the overreliance of 85th percentile speeds on setting speed limits. Throughout my career, I have found that 85th percentile speeds often migrate to the design speed of a roadway.
Driving fast has long been a symbol of freedom. I recently met a planner with the Ministry of Transportation Ontario named Ahmed Aziz, whose graduate thesis was a YouTube video titled “Cars, Cities and Freedom: How automobile manufacturers shaped United States and Canadian cities and culture” (well worth watching). They looked at car ads from long ago. The song “Red Barchetta” by Rush (a band I heard constantly on my favorite radio station growing up) is about a dystopian future where recreational driving is prohibited by “motor laws.” A protagonist weekly drives a hidden sports car. One lyric is “Wind in my hair, shifting and drifting, mechanical music, adrenaline surge.” This captures the essence of driving for many of us. In the proper environment, this is not a problem—but it is when we share roads with vulnerable road users.
I often teach short courses on temporary traffic control and traffic calming to uniformed law enforcement and others. I typically poll them about how fast someone has to be going before they issue a ticket for speeding, and the consensus answer is 10 mph (i.e., 15 kph). Most automated speed enforcement in the United States doesn’t trigger until 10–11 mph over the limit. On a freeway facility, a little speeding rarely creates a major safety issue, but it does on roads with vulnerable road users. Increasing speed from 25 mph (i.e., 40 kph) to 35 mph (i.e., 60 kph) nearly doubles kinetic energy. Why is it that our speeding tolerance is the same for freeways and local streets? There is hope. Automated speed and other traffic enforcement is ubiquitous in Australia. A survey of Australians finds most are reluctant to speed more than 5 kph (3 mph) on non-freeway roads. The ITE Recommended Practice A Guide to Vertical Deflection Speed Reduction Techniques: Planning and Design of Speed Humps, Speed Tables and Other Related Measures documents that speed cushions are just as effective as speed humps at speed control, without the negative impact on emergency services. There is hope for the future of managing speeds and reducing roadway fatalities and serious injuries!