Editor's note: Due to inconsistencies in police reporting of collisions, an earlier version of this article stated that the State Street and Tapawingo Drive roundabout saw the highest number of collisions in West Lafayette. The Exponent regrets this error.
Two of the three most accident-prone intersections in 2019 near campus are roundabouts, according to data collected by the Tippecanoe County Area Plan Commission.
The roundabout at the State Street and Tapawingo Drive intersection is the second-most accident-prone in West Lafayette, with 48 total incidents reported in 2019. Half of the reported collisions were same-direction sideswipes.
The most accident-prone intersection in West Lafayette is the Sagamore Parkway and Salisbury Street intersection, which had 56 accidents in 2019. The third-most accident prone intersection in West Lafayette was the River Road and Tapawingo Drive roundabout with 38 accidents.
“A same-direction sideswipe is when two vehicles are traveling in the same direction, usually side by side, and the sides of the vehicles bump into each other,” Timothy Stroshine, assistant director of transportation at the APC, explained in an email. “For example: Vehicle A is in the left lane and Vehicle B is in the right lane on Sagamore Parkway. Vehicle B swerves slightly to avoid an obstacle in the right lane, causing it to drift into the left lane and hit Vehicle A’s passenger-side door.”
Same-direction sideswipes occur more often in roundabouts but are not generally dangerous in terms of death or severe injury, Stroshine said. In intersections with four-way stoplights, right-angle and head-on collisions are more likely to occur and result in bodily harm.
“Head-on and right-angle crashes are generally the most dangerous types of crashes that can happen,” Stroshine said, “so engineers often look to design roads to lower the chances of these types of crashes. Roundabouts are one solution that this community has used over the past several years.”
The State Street and Tapawingo Drive roundabout could benefit from being a little bigger, according to Andrew Tarko, a civil engineering professor and director of Purdue’s Center for Road Safety. But due to the proximity of the John T. Myers Pedestrian Bridge and two hotels, it cannot be improved.
“The roundabout, for the conditions, is properly designed,” Tarko said. “The traffic requires two lanes. The space was tight so they couldn’t make it a little bigger.”
Still, Tarko said, the intersection is better than a stoplight, though the volume of traffic going through the intersection may lower its effectiveness.
The River Road and Tapawingo Drive intersection was the first multi-lane roundabout in West Lafayette when it opened in late 2017, and was met with complaints about other drivers.
“There is definitely a learning curve on how to navigate them,” said Marcus Smith, interim head engineer for the city of West Lafayette.
Kirsten Gibson, a second-year graduate student, said she frequently sees other drivers make mistakes at roundabouts.
“They make a full stop when the roundabout is clear,” Gibson said. “They stop in the roundabout, they enter when there’s traffic coming, they don’t use the correct exit lane.”
After two close calls in the past few years at the River Road and Tapawingo Drive roundabout, Gibson said she’s now a lot more cautious.
“I slow down, I don’t take chances, I watch every single car and try and get eye contact to know they see me and aren’t going to pull out in front of me,” Gibson said.
Worry increases when traffic is heavy, second-year graduate student Rachel Barton said.
“I almost always stay in the outside lane unless I have to get out on the third exit,” Barton said. “Especially when there’s heavy traffic. I worry about getting hit.”
To help educate drivers, the city released an instructional video in late 2017 and installed additional signage to help direct output, but Gibson wishes more education could be offered.
“Frankly, I’m not sure who has the right of way as a pedestrian. If I’m in the roundabout already and a pedestrian is crossing where I need to exit, do I stop?” Gibson said. “A red stoplight is a clear instruction, roundabouts give more agency to the driver, which is fine, but what if they don’t know what to do with that agency?”
David VanVactor, deputy chief of the West Lafayette Police Department, also advises drivers in the area to take it slow and pay attention to signage and road markings.
“Have a better awareness of the location,” he said. “And, obviously, slow down. It’s not meant to be a racetrack.”
The City of West Lafayette is currently considering adding three more roundabouts as a part of the West Lafayette Downtown Plan. The proposed locations are the intersection leading to the Harrison Bridge, at the Columbia Street and River Road intersection and at the Wood Street and River Road intersection.
The council has delayed the vote for March's City Council meeting.