We have traffic because we drive so far

Afternoon traffic on I-405 near Canyon Park. Photo by SounderBruce.

We are regularly reminded that traffic congestion is growing across the region. The median Seattle metro area worker commutes nine miles to work. What if we could live closer to our workplaces? Drivers would drive fewer miles, and spend less time in traffic. Everybody who lives closer to work would contribute less to the congestion experienced by everybody else. This would reduce traffic even if everybody drives. But there’s a multiplier as denser places have higher transit (and walk, and bike) shares. Reduce travel distances by 10%, and there’s a more than 10% reduction in vehicle miles traveled.

Who has the longest and shortest commutes? The U.S. Census Bureau’s Longitudinal Employer-Household Dynamics has a handy mapping interface to their Origin-Destination Employment Statistics. I’ve charted the length of commute journeys for major cities in the region, per the PSRC classification of Metropolitan, Core, and Larger. (Here’s a similar chart for smaller cities).

The shortest commutes are enjoyed by residents of Mercer Island, Seattle, Bellevue, Kirkland, and Redmond. 75% live within ten miles of their work (vs. 52% for the region). Of course, these are the nearest cities to the two largest employment centers in the region. Commuters from more distant cities to downtown Seattle and downtown Bellevue must travel further.

Among the cities on the chart, the longest commutes are from the exurban communities of Maple Valley, Monroe, Arlington, Lake Stevens and Marysville. 71% of workers who live in those cities are more than 10 miles from their work. 31% are more than 25 miles away. These aren’t the very worst commutes in the region, however. Residents of some of the tiny mountain ‘smaller cities’ drive extraordinarily long distances to work.

Incidentally, Covington and Bonney Lake, both seeking larger city designation so they can grow faster, would have longer commute distances than most of the larger city peer group.

It will surprise few that people who live near Seattle and Bellevue have shorter commutes. But it invites an obvious question. Why is the regional growth strategy constructed around five Metropolitan Cities and 29 Regional Growth Centers? Why not draw more residential development closer to the two dominant business centers?

Continue reading “We have traffic because we drive so far”