Seattle ♥s Humps
- Jan. 25, 2016
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Do speed humps work?
Seattle Department of Transportation (SDOT) started installing speed humps as part of neighborhood greenways and Safe Routes to School projects a couple of years ago. Wisely, SDOT measured speed data to track hump effectiveness. Total speeding on the streets near three elementary schools dropped between 79 – 88 percent after speed humps were installed, and high-end speeding was nearly eradicated, and there was a 90 percent drop in aggressive drivers traveling more than 10 MPH over the speed limit. Speed is the most important factors that determines how seriously a person is injured in a collision and, of course, whether the collision occurs in the first place. So yes, speed humps work.
What is a hump?
Technically, speed “humps” are different from the speed “bumps” you often encounter in parking lots. Built correctly, humps are more gradual and are not meant to bring people to a nearly complete stop. If you are driving or riding a bike at 20 MPH or below, you will not need to adjust your speed to go over them comfortably. If you are moving faster than 20 MPH, however, you will need to slow or face a jolt. And unlike with some speed bumps, the speed humps are not so sudden that they are likely to cause someone on a bike to crash. Seattle’s speed humps will save lives, and they will prevent many people from serious and sometimes debilitating injuries.They will also make neighborhood streets places where people of all ages can live, have fun and get around on foot and bike.Why is Seattle getting many new humps now?
In 2015, Seattle Neighborhood Greenways (SNG) staff came back from a Vancouver BC Study Trip with Commute Seattle, excited to share best practices. Among our take-aways was a Vancouver policy of putting speed humps on all non-arterial streets at EVERY school and EVERY park. SNG staff worked with SDOT Safe Routes to School coordinator Brian Dougherty and Parks staff on adapting Vancouver speed hump policies and we're pleased to report Seattle has just now adopted similar policies!