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close windowCase Study No. 70
Bellevue, WAﾠ
Prepared by Karen Gonzalez, City of Bellevue, WA.
Excessive vehicle speed is a top complaint received by transportation departments, and one of the primary contributors to both vehicular and pedestrian crashes. Although agencies may have a number of tools available for addressing speeds, effective educational tools may be hard to come by.
Protecting and preserving neighborhood livability is a priority for the City of Bellevue. In 1985, the City developed and implemented a Neighborhood Traffic Calming Program to address citizen concerns with excessive vehicle speeds, cut-through traffic, accidents and pedestrian safety. Bellevue’s experience has shown that the majority of speeders in a neighborhood are the residents themselves. Although engineering and enforcement measures are important to curtail speeding, one of the keys to reducing vehicle speeds is changing driver behavior. To this end, the City’s Police and Transportation Departments partnered to educate the community on traffic safety basics, including pedestrian safety.
Excessive vehicle speed was the number one complaint received by the City’s Transportation Department. Although Bellevue has a number of tools in its toolkit for addressing speeds, the City is always looking for new and innovative approaches to addressing this ongoing concern. In 1990, the City found a success story from a police agency in southern California, experimenting with a new technique—a radar trailer. This new technique appealed to the City, and a pilot program began.
A radar trailer is a self-contained portable trailer that houses a radar unit and reader board. As a vehicle passes the trailer, the vehicle’s speed is detected by the radar unit and displayed on the reader board. The idea is to bring a motorist’s attention to the speed they are traveling and how it compares to the posted speed limit. With the help of its electronics staff, the City purchased and constructed its first radar trailer. The next step was to select locations throughout the City for its pilot program, which included both neighborhoods streets and streets in school zones. Typical speed limits on these local and collector streets were 40 km/h (25 mi/h), or 32 km/h (20 mi/h) in the school zones.
Prior to setting out the trailer, speed studies were conducted at several sites and used as the baseline for determining the effectiveness of this new tool. Each morning, the radar trailer was placed by the Police Department’s Parking Enforcement Officer and picked up each afternoon, taken back to the City for storage and battery recharging.
Two weeks following placement of the radar trailer, the Police Department conducted target speed enforcement. This approach provided residents with an opportunity to correct their driving habits and reduce their speed before enforcement began.
The initial cost of purchasing equipment and building radar trailer was approximately $6,000 in 1990. Since that time, the popularity of these units has increased, and manufacturers are now producing them for purchase. Today’s costs range between $7,000 and $10,000, depending on the unit’s features. Funds from the Neighborhood Traffic Calming Program were used to fund the project.
The community response to the radar trailer pilot project was extremely positive. As evidence of this support, many residents and neighborhood groups requested radar trailers in other neighborhood locations throughout Bellevue. Over the past ten years, trailers have been used as a tool for addressing vehicle speeds in residential neighborhoods. When citizens request a trailer, they are placed on a list and are responded to on a first-come, first-serve basis. At times, this creates a backlog of up to three months for placement. To meet this high demand, the City has partnered with local tow-companies to donate their time and help move the trailers around Bellevue.
In addition to their popularity, the radar trailers helped reduce vehicle speeds. Speeds were collected at several of the pilot sites before, during and after placement of the radar trailer. The results showed that vehicles traveled 5-8 km/h (3-5 mi/h) slower than before the unit was placed in-service. Several days following the placement, vehicle speeds increased slightly. However, when adding the element of enforcement vehicle speeds again decreased. Though the trailers were most effective when they were in place, yet they reduced speeds and continue to increase the safety of pedestrians traveling along and crossing streets in the neighborhoods and school zones of Bellevue.
Karen Gonzalez
Neighborhood Programs Manager
City of Bellevue
301 116th Avenue SE, Suite #150
Bellevue, WA 98005
Phone: 425-452-4598
E-mail: kgonzalez@ci.bellevue.wa.us