An interesting shift in traffic is playing out in the Twin Cities area as highways and freeways have become more crowded during midday hours and stay busier longer into the evenings. Night owls have lots of company as motorists are driving substantially more miles when most people are sleeping.
Data from the Minnesota Department of Transportation shows traffic this year has increased at nearly all hours of the day compared with pre-pandemic levels with one exception — the morning rush.
Traffic planners and officials surmise the combination of flex and hybrid work brought on by the pandemic and a huge decline in transit use that has been slow to rebound has led the shift away from traditional traffic patterns in which volumes peaked in the morning followed by a midday lull and a late-afternoon surge.
"We are now seeing a general rise through the day, not just in the morning and evening peaks," said Garrett Schreiner, a freeway operations engineer with MnDOT. "It's not the same commute."
While still some of the busiest hours to travel, freeways are far less crowded between 5 and 8 a.m. than they were before the pandemic. Traffic is down 18% between 6 and 7 a.m. and 12% between 7 and 8 a.m. this year when compared with average traffic volumes in the three years leading up to the onset of COVID, according to the latest counts.
MnDOT measures the number of vehicle miles traveled by using sensors embedded in the pavement, and counts show motorists are putting on 346,000 fewer miles between 6 and 7 a.m. and are logging about 282,000 fewer miles a day between 7 and 8 a.m.
Even a small percentage change in the number of vehicles on the road can mean the difference between free-flowing conditions and congestion.
"That is huge," Schreiner said.
Some of the biggest increases in traffic have occurred between 10 a.m. and 3 p.m., with the largest increase occurring at noon when volumes are up 33%, the data shows. Eric Lind, director of the Accessibility Observatory at the University of Minnesota, said teleworking has changed driving behavior.
Workers may be heading into the office later than in the past, putting more cars on the road at times when traffic used to be lighter. Those working at home may make more discretionary trips during the day. They may go to lunch while waiting for a call or run errands between meetings or when picking kids up from school, Lind said.
"They are doing all kinds of trips that pile up on each other, and that puts more people on the road," Lind said. "Pre-COVID, they would not do that."
Congestion and slowdowns are most likely at 4 p.m., when the highest number of vehicles are on the roads, but the evening rush doesn't fully wind down until well after 8 p.m. Even at that hour the roads are humming as volumes are up 17% over pre-COVID levels, according to the data.
Motor freight and package deliveries might explain why overnight traffic is up over 30%, Lind said.
Days of the week
As traffic builds as the day goes on, it also builds throughout the week. Fridays tend to see the most traffic with Thursdays not far behind. Sundays see the lightest traffic volumes.
Motorists collectively averaged 42.5 million miles on Fridays before the pandemic. Between January and Sept. 17, counts on Fridays "were consistently" over the historic average, Schreiner said. The busiest day: July 21 when motorists logged more than 46 million miles.
Despite all those vehicles on the road, congestion doesn't seem to be much worse, Schreiner said. "Travel is spread out more throughout the day."
But that does not mean motorists won't get caught in backups and slowdowns, and could see them at times when they are unaccustomed to sitting in traffic. "Congestion will occur. It is not predictable when and where," Lind said.
That includes routes that have been frequently plugged up this summer: I-694 in New Brighton and Brooklyn Center, the Crosstown between Hwy. 100 and Cedar Avenue and I-494 between Cedar Avenue and Hwy. 169.
Road construction, large events such as the State Fair, and Twins and Vikings games can also be traffic magnets, and affect mobility, Schreiner said.
What does this all mean?
Schreiner said MnDOT is watching to see if these patterns hold, and considering what steps the agency may need to take to manage congestion. That might mean expanding or shifting hours when ramp meters operate, changing or lengthening hours that EZ Pass carpool lanes are in effect, and when MnDOT dispatches its yellow trucks known as Highway Helpers to help stranded motorists.
A recent U study found when traffic dropped during COVID, drivers in Minneapolis were able to reach 42% more jobs in the same amount of time it took them before the pandemic. As the roads fill up, traffic planners will need to look for ways to encourage people to diversify trips using different methods of transportation, Lind said.
"If we can take advantage of this and provide real alternatives to driving alone, we can keep congestion solved in our lifetime without freeway expansion," wrote Andrew Owen, the study's author.