Consultants assisting the city and university with a Lincoln Way traffic safety study recommend some physical changes to the arterial's intersections with Welch and Stanton avenues and timing alterations to the traffic signals throughout the corridor (Sheldon Avenue to University Boulevard) to reduce wait times.
During Feb. 27 presentations both on campus and to the Ames City Council, Bill Troe, a transportation planner with SRF Consulting, Omaha, said time is the top consideration in this assessment. To have an impact, no solution can add time to anyone's travel, he said.
SRF's recommendations are:
- Shorten the cycles in the traffic signals at all intersections (Sheldon Avenue to University Boulevard) to reduce wait times for everyone using or crossing Lincoln Way (by about 20 percent for drivers and 15-20 percent for pedestrians). Speed limits would not change. City traffic engineer Damion Pregitzer said average speeds through the corridor actually are below the posted limit.
- Shave off 90 feet of Lincoln Way median on either side of Welch Avenue to eliminate places for pedestrians to "perch" when they're crossing against a light. Paint the left turn lanes on Lincoln Way for clarity. Introduce a lead crossing time (4-8 seconds) for pedestrians before vehicles are allowed into the intersection (successfully implemented at University Boulevard's intersections with Sixth Street and Stange Road and the South Duff Avenue/South Fifth Street intersection). Troe said the delay could reduce pedestrian-vehicle accidents by 60 percent.
- Install an accessible pedestrian crosswalk across Lincoln Way on the west side of the Stanton Avenue intersection, but do not add a traffic signal. Slightly extend the curb corners on the south side of Lincoln Way to make pedestrians more visible to drivers. Street lighting improvements may be needed to illuminate the crossing. On-street parking on the south side of Lincoln Way limits visibility for drivers entering the intersection from Stanton, but campustown parking already is in short supply and eliminating stalls might be contested.
The two intersections were targeted for improvements following data collection and analysis in phase 1 of the safety study. The Welch intersection has an elevated number of pedestrian-vehicle accidents and the Stanton intersection an elevated number of vehicle-to-vehicle accidents. Troe also noted that despite the absence of a crosswalk now, the volume of pedestrian crossings at Stanton "rivals any other intersection in the corridor."
If it works, repeat it
Troe said the proposals for Welch and Stanton, if effective, could be implemented at other similar intersections in the corridor in the future. He acknowledged the Stanton proposal is a minor improvement, but could have an impact because drivers know to yield to people in a crosswalk. SRF's alternative proposal for that intersection is to prevent pedestrian crossings by building a continuous Lincoln Way median with a center fence from Welch to Lynn. This option also would prevent left turns at the Stanton intersection.
"The city could come back to this option if the first one isn't enough," he noted.
Councilwoman and adjunct associate professor of English Gloria Betcher, who represents the campustown area, expressed some concern for the Stanton proposal.
"I don't want to give people the illusion they're safe there (Stanton crosswalk) if the traffic doesn't know what to do with them," she said. "I don't think we should be encouraging people to cross there."
Councilwoman Bronwyn Beatty-Hansen said an official crosswalk with curb cuts would make the intersection safer for pedestrians and bicyclists. "People are going to cross there. I cross there. Everyone does it," she said.
The council directed Pregitzer to develop a budget for the Welch and Stanton proposals. SRF documents estimated $10,000-$15,000 per intersection. Pregitzer said the consultants provided a timing plan for the traffic signals. That change would only require staff time and could be implemented within a month, he said.
Education will be ongoing
Pregitzer told council members that educating pedestrians and influencing their behavior will remain a necessary and important piece of safety efforts. He noted the work of city and ISU police officers in promoting pedestrian and cyclist safety along the cororidor. Phase 1 data indicated a 35 percent compliance rate -- pedestrians who activated a walk light and waited for a walk signal. Shorter cycles in the traffic signals could improve compliance -- but pedestrians also have to be aware that changes were made in their favor, he said. Ideally, pedestrians would see a countdown to a walk light, similar to the current countdown to the end of a walk signal.
- Lincoln Way safety study heads into solutions phase, Aug. 3, 2017
- ISU, city team on Lincoln Way safety study, March 24, 2016