Chapter 2 - Where Did Traffic Calming First Develop?

Introduction

Traffic calming is still a relatively new idea in the United States, but its roots lead back to a Dutch city, named Delft. This is where European traffic calming began, as a grassroots movement in the late 1960’s. ITE’s Traffic Calming: State of the Practice tells the story:

“Angry residents of the Dutch city of Delft fought cut-through traffic by turning their streets into “woonerven,” or “living yards.” What were once channels for the movement of cars became shared areas, outfitted with tables, benches, sand boxes, and parking bays jutting into the street. The effect was to turn the street into an obstacle course for motor vehicles, and an extension of home for residents. Woonerven were officially endorsed by the Dutch government in 1976. Over the next decade, the idea spread to many other countries. Laws and regulations were changed to permit woonerf designs in Germany, Sweden, Denmark, England, France, Japan, Israel, Austria, and Switzerland. By 1990, there were more than 3,500 shared streets in the Netherlands and Germany, 300 in Japan, and 600 in Israel.”¹

The United States was later to adopt various measures used by its European counterparts. The U.S. did use street closures and traffic diverters in Montclair, NJ, and Grand Rapids, MI, as early as the late 1940’s to treat problem streets. Berkeley, CA was probably the first to establish a complete traffic calming program when it adopted a citywide traffic management plan in 1975. However, Seattle, WA, may have been the first to do area wide planning, and it now has more experience implementing traffic calming measures than any other community in the U.S. The first area wide traffic calming demonstration was done in Seattle’s Stevens Neighborhood in 1971.

Stevens Neighborhood

Stevens Neighborhood involved a twelve-block area of gridded streets that were used as cut-through routes. Even though bordering arterials had excess capacity, outsiders found it easier and more convenient to use internal streets. The demonstration initially involved a series of temporary diagonal diverters with 50-gallon drums. Since the diverters were placed at both ends of the streets, the neighborhoods own residents became inconvenienced²(Figure 2.1).

Figure 2.1: Stevens Neighborhood Original Traffic Calming Demonstration (very rigid) Source: Traffic and Transportation Division, “A Study in Traffic Diversion in Stevens Neighborhood.” City of Seattle, WA 1974

The neighborhood voted to replace diverters with traffic circles, install half street closures, and redesign a diagonal diverter to permit an additional turning movement. This was Seattle’s first test of what became the workhorse of its traffic calming program – the neighborhood traffic circle. In 1973, permanent landscape circles and diverters were installed to replace the temporary ones (Figure 2.2). Statistics showed a reduction in internal traffic volume of 56 percent, traffic accidents fell from 12 per year to zero per year, and pedestrians found a general satisfaction with the treatment.³

Figure 2.2: Stevens Neighborhood Permanent Traffic Calming Installation (more permeable)

Traffic Calming Evolution

Initially, the woonerven were localized, spot treatments to slow down vehicle speeds in very specific, individual areas. As traffic calming evolved, the focus of the measures expanded into neighborhood wide calming strategies. Neighborhood calming goes beyond spot treatment in attempts to reduce traffic speeds and volumes in an entire neighborhood. The concept of neighborhood traffic calming was recently applied to central business districts in Europe where they are called “strolling zones”. Examples can be found in Chanberry, France (expensive), and in Burgdorf, Switzerland (inexpensive). In Switzerland, there are 21 similar projects implemented or planned which can be seen under the web site, www.modelcity.ch. Australia has also experimented with this type of downtown “pedestrian/car” zones. These are zones built for the pedestrian, while cars are essentially the“guests” in it. Traffic calming moved from neighborhood to major arterial calming. It even escalated to the calming of a few entire towns in Germany!

References

1. Ewing, Reid. Traffic Calming State of the Practice, ITE. August, 1999, Page 10
2. Ewing, Reid, 14-15
3. Ewing, Reid, 14-15

This chapter originally written by Dan Ferster, 1999, as part of a senior project.