Most assessments measuring congestion focus on the number of extra hours individual motorists spend stuck in traffic each year. But a new study from University of Minnesota researchers takes a different approach.
The "Access Across America: Auto 2015" study looks at how congestion collectively affects the ability of people to get to and from jobs. In other words, it looks at how many jobs drivers can get to in a specified amount of time and how many they can't.
There are roughly 1.7 million jobs in the 13-county metropolitan area as defined by the U.S. Census Bureau, and when traffic is moving at freeway speeds, drivers can get to any of them in 60 minutes or less. In 30 minutes, under ideal conditions, drivers can get to 1 million jobs, and for commutes lasting 10 minutes or fewer drivers can get to 100,000 jobs, said researcher Andrew Owen of the U's Accessibility Observatory.
Of course, individual results will vary depending on your starting point, how far you drive to your job and at what speed.
The point is that congestion doesn't seem to be impeding our ability to get to work as much as it does in other U.S. cities, although anybody who endures the daily morning logjams on northbound I-35W from Burnsville to downtown Minneapolis, westbound Interstate 94 from Woodbury to downtown St. Paul and the knots that typically form on Hwy. 169 in Golden Valley, the Crosstown and along the I-494 Bloomington strip may disagree.
Owen collected data from the census bureau to plot where job centers are. Next he gathered traffic data covering 11 million unique blocks across the country from TomTom, a Dutch company best known for its mapping and GPS navigation systems. Then, using multiple computers, he compared the impact congestion has on Twin Cities commuters with those in 49 other major metro areas. He calculated travel times from each of those locations for drivers at 8 a.m., when congestion is likely, and compared them with what a trip would take at 4 a.m. when freeways are wide open.
For example, if I lived at the newspaper's headquarters at 650 3rd Av. S., Owen's research could tell me how many of the 1.7 million jobs in the metro I could get to with a 10-, 30- or 60-minute drive in noncongested conditions. With a 30-minute drive, say that number was 100,000. Factor in congestion, and that drops to 90,000, or a 10 percent reduction. Using those metrics, it can help job seekers determine where they want to live for higher job accessibility and tell employers where to locate to have access to a larger workforce.
"The question is how much can I get for my 30-minute commute? How much will my time buy?" Owen said. "We have better access to jobs than most other places."
The Twin Cities came in 23rd when it comes to loss of job access due to congestion, a 10 percent drop for those who can normally can get somewhere in 30 minutes under free flow conditions. Not surprisingly, traffic-riddled Los Angeles and nearby Riverside topped that list with commuters able to reach a third fewer jobs during congested periods. Second was Boston at 24 percent, followed by Chicago and San Francisco at 23 percent, Houston, New York and Seattle at 21 percent, and Phoenix at 16 percent.
While our roads are getting more crowded, it could be a lot worse. "This does not mean drivers won't see congestion here, but if they leave, they'll be thankful when they come back," Owen said.
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