The Environmental Sciences and Management Department and the Civil and Environmental Engineering Department recently collaborated in a study designed to measure the air quality of the protected bike lane running along Southwest Broadway Avenue at Portland State.
The study was conducted by placing two ultra-fine particle detectors on the side-view mirrors of a car parked between the cycle track and traffic flow. The results of the study found that the risk of inhaling dangerous
ultra-fine particles is significantly reduced as one becomes further away from traffic.
“I think it’s nice to know that getting to the side of a bus, even just a little bit, can decrease your overall exposure,” said Christine
Kendrick, lead researcher on the project and a Ph.D. student in the Environmental Sciences and Management Department.
According to Kendrick, ultra-fine particles are the most dangerous element of the exhaust from vehicles.
“This type of bicycling infrastructure design has the potential to lower exposure,” Kendrick said.
The findings suggest that with the cycle track, distance from traffic alone accounted for the significant drop in air pollutants.
However, the significance of the “barrier effect” that a parked vehicle poses cannot be ruled out, she said. As a result, additional research is needed to answer that question.
“I was excited by the idea of being able to measure the health benefits of what the cycle track appeared to offer,” Kendrick said. “Bringing these two departments together led to a natural exploration of this kind of question.”
The cycle track is designed to help cyclists feel more comfortable while riding in the city by moving the parking lane 10 to 11 feet from the curb, creating a buffer zone for cyclists from traffic. Broadway is the first street to be modified in this way in order to make bicycling a part of daily life in Portland.
Kendrick’s own sentiments concerning bicycling in the city are precisely why she was energized to conduct this study. According to Kendrick, the safety aspects of biking, whether it’s physical safety or air quality, shouldn’t stop someone from riding.
“Hopefully this research will help provide some positive rhetoric to the conversation,” she said.
Along with Kendrick, this interdisciplinary research team consists of Environmental Sciences and Management Department Chair Dr. Linda George and Dr. Adam Moore, Dr. Ashley Haire, Dr. Alexander Bigazzi, Dr. Miguel Figliozzi and Dr. Christopher Monsere from the Department of Civil and Environmental Engineering
According to Monsere, the question of air quality as affected by traffic flow has the potential to create some large gaps in science because environmentalists tend to broadly categorize traffic flow, while traffic flow engineers that do emission work will generalize the environmental aspect.
However, together the team was able to bring in the micro-measurements from each of their independent fields and put them to bear on this issue.
“They have all the air quality monitoring equipment, and we have all the traffic-monitoring equipment,” Monsere said. “There’s a great synergy between us.”
From a civil engineering viewpoint, the cycle track design will not work for all streets, according to Monsere.
“But it is a good design tool city planners can use when planning multi-use road systems,” he said.
There is also a learning curve that the vehicle-bound public had to overcome when the cycle track was initially installed. Monsere witnessed some people sitting behind parked cars for minutes at a time, apparently thinking they were in a moving lane of traffic. This caused many drivers to become frustrated.
Additionally, drivers lose some visibility of the bicyclists when coming up to an intersection. Training and increased vigilance is required from both motorists and cyclists as Portland continues to experiment with different multi-use roads.
Studying the effect of road and traffic signal design on air quality along Southeast Powell Boulevard is the research team’s next project, according to Kendrick. ?