This "before-and-after" video looks west down 19th Street, toward the street's intersection with Barker Avenue. Employees from the city's traffic division used a bucket truck -- one they normally use to change light bulbs in traffic signals -- to help them record this video of the intersection during the beginning of evening rush hour (just after 5 p.m.) on two different days: one, in June 2003, when the intersection had four stop signs controlling traffic; and a second, in the fall of 2004, after a roundabout had been installed at the intersection instead.
We sped up the time on the city's video for each view, condensing several minutes into just over 30 seconds. David Woosley, the city's traffic engineer, says that that same number of vehicles are going through the intersection in each instance. The only difference? Before the roundabout, vehicles would get backed up on 19th, at times almost all the way to Massachusetts Street at the top of the screen. After the roundabout? Only a handful of vehicles came to a stop, yielding to traffic already in the circle.
Woosley concedes that the roundabout isn't perfect - "it's a compact roundabout," he said, given the constraints of other properties nearby - but notes that traffic flow has improved and the number of accidents has fallen, especially collisions that involve injuries.
Published on September 29, 2008