Reducing Traffic Speed

Background

Pedestrians account for 13 to 17 percent of all motor vehicle fatalities, totaling nearly 6,000 deaths annually (1). More than half, 55 percent, of all pedestrian deaths by automobiles occur on neighborhood streets (2). The number of bicyclist fatalities is lower than that of pedestrians--approximately 800 per year (1)--but the injury rate is very high, at approximately 583,000 per year (3). Children ages 5 to 14 account for nearly 30 percent of the fatalities and more than 60 percent of the injuries (4). Thirty-four percent of bicycle fatalities occurred on local--as opposed to major--roads (5).
As the number of cars being driven increases, there is a growing clash between motorists looking for unclogged short cuts, and residents who want their neighborhood streets free from speeding commuters. Studies show that a ten-mile per hour increase in speed, from 20 mph to 30 mph, increases the risk of death for a pedestrian in a collision nine-fold (2). If a car going 20 mph hits a person, there is a 95 percent chance that the person will survive. If that same car is going 30 mph, the person has just over a 50 percent chance of survival (2). Many communities are turning to traffic calming techniques to reduce vehicle speeds in residential neighborhoods.

Policies

1. Use traffic calming techniques to reduce vehicle speeds.
   
   Traffic calming designs include narrowing the roadway, changing pavement surfaces, installing speed bumps, erecting barriers and constructing roundabouts (a form of traffic circle). These approaches are very effective at reducing speeds and preventing collisions (6). Reducing traffic speeds not only reduces the occurrence of crashes, it may reduce their severity, as slower speeds increase braking distances and reaction time. These measures improve pedestrian and bicyclist safety, and are appropriate in any area where people live, work and play.
   
   
2. Re-route through traffic from residential streets to arterial streets.
   
   Sometimes drastic measures are required to keep traffic on intended routes. In San Francisco, California, more than 4,000 vehicles per day used a one-block residential street as a short cut to a freeway onramp. To keep the traffic on the main route to the onramp, officials placed steel barriers at one end of the street and movable wooden barriers at the other - discouraging commuters but still allowing residents access (7).
   
   

Effectiveness Data

Reducing the speed of motor vehicle traffic on residential streets using traffic calming techniques reduces injuries to pedestrians andbicyclists by 50 to 75 percent (8). A number of cities have embraced traffic calming measures:

• Seattle is a national leader in using traffic calming devices in residential neighborhoods and has had great success in reducing traffic crashes and speed. In Seattle, the city's traffic calming program, which involved the installation of traffic circles, reduced pedestrian collisions by more than 75 percent (2).



• In Portland, Oregon, traffic circles reduced the number of reported accidents by 58 percent (2).



• New York City's comprehensive traffic safety strategies include many traffic calming techniques, including the installation of 358 speed humps in 215 locations. In the last eight years, pedestrian fatalities have gone down by 51 percent (9).

Contacts

Michelle Garland, Campaign Analyst
Surface Transportation Policy Project
1100 17^th Street, NW, 10^th Floor
Washington,, DC  20036
(202) 466-2636
mgarland@transact.org
 
 

References

1. Fatality Facts: Pedestrians. Insurance Institute of Highway Safety, 1999. Web site: http://www.highwaysafety.org/safety_facts/fatality_facts/peds.htm.
   
   
2. Mean Streets: Pedestrian Safety and Reform of the Nation's Transportation Law. Surface Transportation Policy Project and Environmental Working Group. Web site: http://www.transact.org/Reports/Mean/for.htm.
   
   
3. Bicycle Injury Fact Sheet. National SAFE KIDS Campaign, 1999. Web site: http://www.safekids.org.
   
   
4. What's New at DOT? New York City Department of Transportation, September 27, 1999. Web site: http://www.nhtsa.dot.gov/people/ncsa/tsf-1998.pdf.
   
   
5. Fatality Facts: Bicycles. Insurance Institute of Highway Safety, 1999. Web site: http://www.highwaysafety.org/safety_facts/fatality_facts/bikes.htm.
   
   
6. Seattle Transportation Strategic Plan (TSP). Web site: http://www.pan.ci.seattle.wa.us/td/tsp.asp.
   
   
7. Neighborhood Beats the Rush of Traffic on Tiffany Avenue. San Francisco Chronicle, February 18, 1997. :C1.
   
   
8. Action Plan for a Bike Friendly San Francisco. The Program of the San Francisco Bicycle Coalition.
   
   
9. Perez-Pesa R. Rushing Roulette on Mean Streets: Where New York Pedestrians Risk Life and Limb Every Day. The New York Times, December 13, 1996.
   
   

Acknowledgements

Barbara Alberson, M.P.H., Chief, State & Local Injury Control Section, California Department of Health Services

Valodi Foster, M.P.H., Health Education Consultant, State & Local Injury Control Section, California Department of Health Services

Alexander Kelter, M.D., Chief, Epidemiology & Prevention for Injury Control, California Department of Health Services

Chris Miara, Associate Director, Children's Safety Network, Education Development Center

Richard Schieber, M.D., M.P.H., Technical Advisor, Division of Unintentional Injury Prevention, CDC National Center for Injury Prevention & Control

Anne M. Seeley, Active Communities Coordinator, Physical Activity & Health Initiative, California Department of Health Services

Roger B. Trent, Ph.D., Chief, Injury Surveillance & Epidemiology Section, California Department of Health Services

Lynn Walton-Haynes, Research Scientist 1, California Department of Health Services

Diane Winn, R.N., M.P.H., Associate Director, Injury Prevention Research Group, University of California, Irvine

Tina Zenzola, M.P.H., Assistant Director of Programs, California Center for Childhood Injury Prevention


We extend special thanks to the California Center for Childhood Injury Prevention (CCCIP) for their extensive contribution and commitment to the production of this publication.