Drive reader Donovan noticed yellow plastic posts have been placed in the center lanes at the intersection of Ford Parkway and Cleveland Avenue in St. Paul's Highland Park neighborhood.

"What is the purpose of these devices?" he asked in an e-mail. "Can we expect to see more of these around town?"

The posts form a "hardened centerline" and were put up this summer as part of a University of Minnesota study looking to see if certain road treatments will cause drivers to slow down and reduce crashes involving pedestrians.

Nichole Morris with the U's HumanFIRST Laboratory has been researching driver behavior when encountering pedestrians for the past five years. A multipronged study from 2018-2019 employed several methods, including outreach programs such as St. Paul's "Stop for Me" campaign, police enforcement at selected intersections and blue signs displaying the percentage of drivers who stopped for pedestrians crossing the street. Low-cost methods such as the plastic posts were also part of the study.

Results showed a driving culture shift at both the test intersections and citywide, with a higher percentage of drivers stopping by the time the study wrapped up, Morris said.

But it also left a question unanswered. Can we have the same success without police stationed at crosswalks handing out $100 citations to violators who fail to yield to pedestrians?

That led to this year's study in partnership with the Minnesota Department of Transportation and Minneapolis and St. Paul. The idea was to see if low-cost treatments alone, like the posts in the middle of Ford Parkway, could achieve the same results.

"They create an obstruction in the roadway," Morris said. "We hope they make motorists slow down as they turn and make them mindful of the presence of pedestrians."

Nearly 2,600 pedestrians have been hit in Minneapolis and St. Paul — an average of 1½ a day — over the past five years, according to data Morris pulled from state crash reports.

Morris and a team of researchers are eyeing 16 "risky" intersections in each city through the end of October. About half are outfitted with plastic lane delineators, bump outs at corners that shorten the crossing distance for pedestrians and stop lines painted on the pavement encouraging motorists to stop further back from corners.

The jury is still out. At 15th Street and Chicago Avenue S., for example, there were days when not one vehicle stopped, Morris said. After treatment was installed, compliance rose to 70%, and researchers were "ecstatic," she said. But when traffic lights were turned back on at nearby 8th and Chicago, speeds at 15th and Chicago were higher and progress was lost.

"Treatment at one location can make traffic calmer at another." Morris said. "What we want to happen is that we would see improvements at all intersections."

Blue signs posted in each city show 64% of drivers in St. Paul yielded to pedestrians last week while only 35% did in Minneapolis. The city has been slow to install treatments, which may explain why it is lagging, Morris said.

Morris has issued the Twin Cities Safety Cup Pledge. It calls for drivers to look for and yield to pedestrians when turning, and for those on foot to obey traffic signals and cross only at crosswalks.

"If people can make a plan, they are more likely to carry out safe behavior," she said.

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