The Speed Hump Report

Data shows that speed humps work.

Data shows that speed humps work.

 

Children are safer when cars move at low speeds  their schools.

Children are safer when cars move at low speeds around schools.

Earlier this year, we told you about SDOT’s plans to install speed humps near schools to encourage more drivers to travel at or below the speed limit. So far this year, SDOT has installed speed humps adjacent to six schools in Seattle: Olympic Hills Elementary, Thurgood Marshall Elementary, Emerson Elementary, Thornton Creek K-8, Eckstein Middle School and Explorer Middle School.

The goal of installing speed humps near schools is to lower vehicle speed where a large number of kids are crossing the street during arrival and dismissal. But do they work? We often hear from people who question whether speed humps, which are only 3 inches high, could possibly change driver behavior. SDOT has increasing evidence showing that speed humps are extremely effective at reducing speed and improving safety. Below are the results of before and after studies SDOT conducted after installing speed humps at three schools in different neighborhoods in Seattle. At all three schools, the percent of drivers exceeding the speed limit decreased more than 70%. Perhaps more impressive, the percent driving more than 10 mph over the speed limit decreased by more than 80%.

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You might be thinking ‘Alright, so they’re effective. Big deal.’ Oh but it is a big deal! Drivers traveling 10 mph or more over the speed limit are some of the biggest threats to kids walking and biking to school. Slowing down allows drivers to stop at a shorter distance which can prevent a crash from happening in the first place. Not only that, vehicle speed itself is a major factor in whether someone walking or biking is killed or injured if hit by a car. A pedestrian hit by a car that’s traveling 35 or 40 miles per hour is likely to be killed, while a pedestrian hit at 20 miles per hour has a 95 percent chance of survival.

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With approximately 30 percent of Seattle streets lacking sidewalks, in some neighborhoods kids walking and biking to school have no choice but to share the street with vehicles. One of the great things about speed humps is that they work during school arrival and dismissal and throughout the day. By reducing aggressive speeders on streets where children are walking or biking to school, SDOT is making our streets safer for everyone.