Tag Archive: speed bumps

20 MPH Streets Start With Schools

January 31, 2016
by Cathy Tuttle

Overwhelming Evidence of Speed Hump Effectiveness
Overwhelming Evidence of Speed Hump Effectiveness

It’s official. Seattle Department of Transportation (SDOT) will engineer safe streets around ALL Seattle schools!

Speed humps are highly effective, inexpensive, and quick to install. Seattle Neighborhood Greenways has been working closely with SDOT on a policy of engineered speed bumps around all schools, based on the Vancouver BC model of traffic calming on non-arterial streets in all School Walk Zones.

Speed bumps will be prioritized using the Vision Zero and Race & Social Justice lenses in the Safe Routes to School Action Plan. (That means the schools with the highest need get speed humps first.)

People who live in school zones that that are not highly prioritized for funding may request speed hump funding through Neighborhood Street Fund or Neighborhood Matching Fund.2016 SDOT Speed Hump Policy page 1

The policy states “To discourage speeds above 20 mph all day, speed humps may be routinely installed on all non-arterials that are signed with 20 mph school speed zones. SDOT has evaluated the effectiveness of speed humps and speed cushions in school zones and found they are effective at reducing … speed to near 20 mph; and they nearly eliminate top-end speeders who drive more than 35 mph that pose the greatest danger for children walking and biking in school zones.(emphasis added)”

Read the complete Speed Hump Policy here.

 

 

Speed Bumps to the Rescue!

by Cathy Tuttle
October 28, 2014

Speed bumps work

What’s black and white and gray all over?

Lake City Greenways volunteer Monica Sweet was impressed with the speed bumps she’d seen in other neighborhoods. She wanted slower, safer streets where she lived on NE 123rd in Lake City. With no sidewalks and drivers that seemed to rip through her neighborhood at high speeds, speed bumps seemed to offer a simple, inexpensive yet effective safety solution.

After a great deal of back and forth with the Seattle Department of Transportation (SDOT), whose staff tried to convince Monica to put in small traffic circles, Monica and her local greenways group prevailed and soon speed bumps will make another Seattle residential street safer for people who walk and bike.

In related news, SDOT just completed the before and after study of vehicle speed on nearby NE 130th Street where speed bumps were installed in the summer of 2014.

According to Brian Dougherty, SDOT Senior Transportation Planner:

“The study shows that the speed humps have had a big impact, reducing the number of drivers traveling above the speed limit. The biggest change is the reduction in the number of ‘top end speeders’ which as you know are the most dangerous for people walking and biking. We show a 90% reduction in these aggressive drivers traveling more than 10 mph over the speed limit… Before and after speeds were measured for one full week using pneumatic tubes.”

* P.S. You may hear the terms speed humps and speed bumps used interchangeably by traffic safety professionals. Speed “humps” are actually the official term but according to our friends in Portland traffic engineering, the signs that said “Humps Ahead” were frequently stolen by the public but “Bumps Ahead” were left to perform their traffic calming duty.