Pedestrian Safety Guide and Countermeasure Selection System

 

Case Study No. 52

Traffic Calming Program

Sarasota, Florida

Prepared by Natalie Rush, Transportation Planner, City of Sarasota, Florida.

Problem

Residents of Sarasota were concerned about speeding vehicles, motorists cutting through residential streets instead of using arterials, and pedestrian safety while crossing streets. Specifically, the Gillespie Park neighborhood was concerned about the safety of children crossing the street to play at the local park.

Background

Sarasota was one of the first communities in the country to develop a traffic calming program.

According to the City's printed Traffic Calming brochure, the function of local residential streets is not just to act as a corridor for vehicular traffic. They are also for social interaction, walking and bicycling. Each residential street will have these ingredients in different proportions but no one function should dominate over all others. Traditional Traffic Calming adheres to this assumption and can be defined as: the combination of mainly physical measures that reduce the negative effects of motor vehicle use, alter driver behavior and improve conditions for non-motorized street use. Traffic Calming changes the look and feel of a street. It does not discourage vehicle travel but it encourages automobile drivers to operate safely with consideration for others on the street. It works to improve the quality of neighborhood life by creating safe attractive streets, and providing and promoting pedestrian and cyclist activities.

Solution

The Sarasota Traffic Calming Program involves public participation in the planning and design process. Residents also conduct before and after studies to ensure that the devices are effective. When speeding and pedestrian safety problems arise in a neighborhood, the Engineering Department forms a list of neighborhood residents that would like to participate in a Traffic Calming Task Force to help design a neighborhood Traffic Calming Master Plan.

To aid them in creating the plan, this Task Force is presented with design options, such as speed tables, neck outs, medians, etc., and is given a significant amount of baseline information, including: traffic counts, resident and business input, current street design dimensions and conditions, funding guidelines, and traffic calming warrants. Upon approval by consensus of the Task Force, the plan is presented to the neighborhood at an open house for the community to view, comment, and vote on the plan. Finally, a public hearing is held before the City Commission. If the plan is approved at the hearing and funding is available, the plan is implemented.

One location where residents identified the need for traffic calming was near Gillespie Park. Using the process described above, the neighborhood Task Force decided to install raised crosswalks at the intersections near the park and speed tables at a mid-block location on an adjacent street. In addition to slowing vehicle speeds, raised speed tables improve the visibility of children crossing the street and provide a highly accessible crosswalk for pedestrians with disabilities. The improvements near Gillespie Park cost $31,500 and were paid with City funds. Similar projects have been completed throughout the City.

Results

Traffic Calming Program

To date, the City has planned and implemented 12 traffic calming projects, including more than 90 speed humps on its streets. In recent years, the public has requested more traffic calming projects than can be accommodated by the budget of the program, only $150,000 per year.

Public response to traffic calming measures has been predominantly positive. In several cases, residents of one neighborhood have heard about the pedestrian safety benefits and speed reduction effects of traffic calming projects in another neighborhood, and started the process in their own area.

In addition to budget constraints, one challenge for the program is determining the best placement of speed tables on roads fronted by narrow, 50 ft wide residential lots. It can be difficult to avoid placing the devices in front of driveways, mailboxes, and next to drainage inlets in neighborhoods with lot sizes this small or smaller.

Speed Table Effectiveness

Between 1996 and 2000, the City documented the effects of speed table projects on traffic speeds, traffic volumes, and cut-through traffic at nine locations throughout the city. All streets had a posted speed limit of 25 mi/h and carried between 240 and 1460 vehicles per day.

Traffic speeds decreased at all nine locations. Considering all sites, the average 85th percentile speed before the speed table installation was 35.1 mi/h. Afterward, speed lowered to 28.9 mi/h, a decrease of 17 percent.

Speed tables had a mixed effect on traffic volumes, increasing at three and decreasing at six of the locations. Although the change in traffic level at each site ranged from a 29 percent decrease to a 42 percent increase, over all nine locations the traffic levels decreased by about 11 percent.

Finally, Sarasota studied the effects of the speed tables on cut-through traffic. Before the speed tables were constructed, the proportion of traffic using the street for cutting through ranged between 10 and 88 percent. While cut-through traffic increased at three of the sites, it decreased at the other six. Change in cut-through traffic ranged from a decrease of 49 percent to an increase of 87 percent.

In summary, this study showed mixed results with regard to speed table impacts on traffic volumes and cut-through traffic, but significant benefits in the area of speed reduction. Slower speeds and lower traffic volumes should contribute to a safer environment for pedestrians, especially in areas where many people cross the street, such as near Gillespie Park.

Contact

Natalie Rush
Transportation Planner
City of Sarasota
1565 First Street
Sarasota, Florida 34236
Office Phone: 941-954-4180
Email: Natalie_rush@sarasotagov.com