Portland's transportation network and land use system offer a mixed blessing for the region's commuters, according to a report released Thursday by the Texas Transportation Institute.
The report finds that the Portland urban area's traffic delays – quantified as a Travel Time Index – is 13th worst in the country. But the report also says the Portland region's road network has among the fewest users per capita in the country, while its transit usage per capita is ranked 10th among large cities.
First, the bad news for the Portland region – our roads are pretty congested. The institute looked at how long a commute should take under ideal driving conditions – think the Banfield Freeway at 2 a.m. – and compared that to how long that commute actually takes – think the Banfield at 4:30 p.m.
By that definition, a commute in Portland takes 123 percent as long as it should, ranked 13th in the country. Portland's urban area, as ranked in this study, is the 23rd largest.
But some Portland proponents have argued the methodology is flawed because Portland is a relatively compact city. Whereas commuters in, say, Raleigh or Memphis (which tied at 44th-worst in the index) are commuting longer distances at higher speeds, and cities like Dallas and Phoenix have sprawling freeway networks that generally are free-flowing except at peak hours, most of Portland's freeway network is fairly closely tied to the city's core.
For example, Loop 202, an 8-lane freeway around Phoenix's eastern suburbs, extends as far out as 30 miles from the city center. A freeway 30 miles out from downtown Portland would be in Buxton, Woodburn or Multnomah Falls – areas without much development. Phoenix might have the same amount of congestion in the central city, but free-flowing traffic on Loop 202 improves its Travel Time Index score.
Chief among the critics of the Travel Time Index is Joe Cortright, a Portland-based researcher and a senior policy advisor for CEOs for Cities. He said Portlanders drive less than the national average, but people in Nashville drive more. According to the Texas Transportation Institute, Nashville residents spend 208 hours per year in their cars on average; Portlanders spend 146 hours.
Yet Nashville ranked 36th in the Travel Time Index, to Portland's 13th worst.
"Number one, there isn't a best measure," said Tim Lomax, the Texas study's primary author. "Number two, it has to do with what your vision of your city is. Having several measures allows you to learn more than if you just looked at one."
Some of the other measures included:
Freeway use: Portlanders drive about 13 million miles daily on the area's freeways. On the surface, that seems like a lot, but Sacramento, with 100,000 fewer residents, has 2.2 million more vehicle miles traveled on freeways every day. Among the 47 cities in the study with more than 990,000 people, Portland ranked 38th in freeway miles driven per capita.
Surface street use: The region's surface street use was slightly higher than its freeway use, with 13.1 million miles traveled daily on arterials. Per capita, that made Portland's surface street driving seventh lowest among those 47 cities. Incidentally, Portland's ratio of freeway traffic to surface street traffic was one of only four cities' that was about even.
Transit use: Portland's transit system saves 5.4 million hours of congestion from the city's road network, 10th best per capita among those top 47 cities. The only other moderate-sized cities in the top 10 were Salt Lake City and Baltimore.
Where was Portland decidedly average? The 23rd-largest city ranked 21st worst in fuel waste, 25th in cost of congestion and 23rd for congestion cost per peak auto consumer.
Lomax acknowledged that the report needs to get better at tracking other alternatives to vehicle commuting. But, he said, inconsistencies in data reported by states makes it difficult.
"Let's see about looking at cycling, walking or working at home, and give you credit for those activities," he said. "That will lead us towards not just a roadway-based, but more of a person-based report. That's something we'd really like to do."
Cortright, who released a report last year saying Portland's traffic was the 44th worst in the country among the 51 largest cities, said a new national benchmark – not just the Texas Transportation Institute's study – would benefit policymakers as they look at transportation planning.
"What's needed here is for the U.S. Department of Transportation to convene a diverse group of people and go through a peer review process and assess the metrics and have a good open debate," he said.