Name: Congress Heights Traffic Calming and Safety Study
Client: District of Columbia DOT
AEC firm: KCI Technologies Inc.
Completed: March 2008
Residents of the 80-year-old neighborhood known as Congress Heights were tired.
Tired of asking for stop signs and speed humps, tired of waiting up to half a year for a response, and tired of piecemeal solutions that rerouted lead-footed drivers to streets where they'd continue speeding with impunity.
Instead of conducting traffic counts and speed studies on individual streets, District of Columbia traffic managers realized the only way to break the cycle was to implement a communitywide solution. So for the department's first comprehensive traffic study, they asked their consulting partner to work with all stakeholders — not just residents, but business owners, law enforcement, and school officials as well — to identify safety issues, consider new technologies, and develop an implementation plan.
In addition to reviewing street geometry, traffic volumes, accident information, and speed results on selected streets, KCI transportation planners studied neighborhood characteristics such as residential and commercial areas, schools, senior facilities, community and recreation centers, bus routes, parks, and fire and police stations. The resulting short- and long-term strategies incorporate technology the department hasn't used.
Nine locations. The LED lamps of rapid-flashing beacons flash yellow when activated by pedestrians. They can be placed either overhead or side-mounted in advance of or directly at crossings.
Four locations. HAWK (High-intensity Activated crossWalK) signals consist of flashing yellow, solid yellow, and solid red signals; a sign instructing drivers to stop on red; and a pedestrian overhead sign.
When pedestrians push the button, the overhead signal begins flashing yellow, then solid yellow and solid red to stop drivers. A flashing red light tells drivers to proceed when it's safe.
One location. In-roadway warning lights mounted in pavement near crosswalks.
The department's first step was to immediately install speed humps, speed tables, and stop signs on the 10 most-dangerous streets. Residents and business owners say the devices work: Traffic has slowed.
Speed humps and tables, crosswalks, rapid-flashing beacons, HAWK signals, and street conversions can be deployed within six months to a year. Longer-term recommendations — curb extensions, pavement removal, and landscaping at an intersection — are scheduled to be implemented over one to three years.
KCI suggested that the department measure the plan's effectiveness at seven locations that represent varying neighborhood settings and characteristics. The studies would document speeds, volumes, and pedestrian-related accidents before and after traffic calming and safety measures devices are installed.