A complicated circle will be made simpler this summer when the crash-prone, double-ring Bell Tower roundabout is trimmed back to a single ring.
The city of Raleigh will apply pavement stripes and raised plastic domes to herd two lanes of traffic into one lane around the circle at Hillsborough Street and Pullen Road. The $10,500 project is to be finished by the end of July, before traffic picks up for the fall semester at nearby N.C. State University.
The change is aimed at slashing accident rates that have stayed stubbornly high since the eccentric roundabout opened in mid-2010. Raleigh police have logged more than 100 crashes in less than two years.
Most involve cars in the circle that collide with cars entering from eastbound Hillsborough. The Hillsborough drivers usually are ticketed for failing to yield right-of-way, as posted signs remind them to do.
Traffic engineers are not ready to admit the roundabout was made wrong, but they hope the retrofit will make it right.
“I don’t think it was a mistake per se,” said Jed Niffenegger, Raleigh’s senior transportation engineer, who was not part of the original design team. “When you design stuff, you have to assume drivers are going to obey the traffic signs and markings.”
Engineers also say they generally do not interview drivers who’ve had crashes. When the Road Worrier spoke with more than a dozen drivers involved in Bell Tower run-ins, many said they were befuddled as they tried to dodge cars in tight, twin rings of traffic.
Jim Dunlop, a DOT engineer who helped design the original roundabout and its planned fix, also declined to call it a mistake. He said the Bell Tower roundabout has helped ease traffic congestion on Hillsborough.
He said the project had ended a history of high-speed crashes and violent injuries at Pullen, and he noted that the Bell Tower roundabout accidents were mild fender-benders – with only a couple of minor injuries.
Still, he said, it’s important to cut that high crash rate.
“Out of 100-plus roundabouts in the state, this is the only one where we’ve had the problem with crashes,” Dunlop said. “And it’s the only one with two lanes (on Hillsborough) crossing two lanes (in the roundabout). We’re learning from this.”
At the outset, engineers knew that drivers would find the Bell Tower roundabout tricky. They took the unusual step of publishing an illustrated navigation guide before it opened in 2010 as part of a $9.9 million makeover for eight blocks of Hillsborough.
In the past two years they have worked with NCSU officials on education campaigns for university students. Crash reports do not show large numbers of students involved.
Some street designers favored a single ring when planning began in the late 1990s. City officials ultimately decided they would need two rings to handle an expected growth in traffic.
But the car counts have gone down since then, not up, from about 21,000 a day in 2007 to 18,000 last year.
“When the project was originally designed, Hillsborough carried a whole lot heavier volume than it currently does,” Niffenegger said.
It could be that some drivers were spooked by that quirky circle.
“I have no doubt that there are people who are avoiding the area just because they don’t like this,” Dunlop said. “Hopefully we’ll tweak this, and they won’t feel uncomfortable driving this roundabout.”