Last week, the Texas Transportation Institute released its big annual study of traffic across the country, the Urban Mobility Report (pdf), which ranks the traffic congestion and commutes of every major city in America.
By their count, Portland has the 23rd worst commute in the nation, with drivers delayed an average of 36 hours per year thanks to traffic.
The report has some interesting and worthwhile data, like seeing how much gas and time is wasted because of traffic jams, but Portland economist Joe Cortright shows some serious flaws in their rankings. His group, CEOS for Cities notes that the traffic rankings don’t account for the length of time people actually spend driving, but just rank based on delays. That means cities that sprawl get good rankings, whereas more compact cities are dinged for density.
“For example, consider Nashville and Portland,” writes Cortright. According to the report, Portland has a worse traffic problem than Nashville, with and 36 hours of delay per year per traveler, compared to Nashville, which has an average 35 hours of delay. But the data also shows that the drivers in Nashville have to drive farther to get to their destinations and wind up spending a total of 268 hours per year commuting compared to the average Portland commuter who travels only 193 hours per year. The report “completely misses the importance of land use planning as a key to reducing the burden of peak period travel,” concludes Cortright.
This is a big deal, because congestion is used as an excuse to build more and larger freeways, when a solution to actually cut down on time wasted in traffic is to build denser cities.
Portland: – City 145.4 sq mi
Nashville: Consolidated area: 526.1 sq mi
I’d say Nashville absolutely creams us (always in the good way) in terms of commuter/miles traveled. They should have 3x the numbers they do. They don’t because their population metro area is also much smaller. So is this the best comparison, period?
Are we now blaming larger cities because they are large?
Ever notice how “economist” Joe Cortright always seem to appear out of the woodwork to make whatever argument is convenient to the Portland planning establishement?
Also his argument makes no sense. Portlanders spend longer in their cars than those in Nashville AND they are sitting in delayed traffic during that time. How is that better than driving for a shorter period on an open road?
Needless to say, I trust the hard data in the Texas study over Mr. Cortright’s feelings.
@Blabby – You’ve got one piece of it backwards, I think. Folks in Nashville spend 268 hours per year driving compared to our 193, so they spend a LOT more time driving than we do, even though we have one hour more traffic jam per year than they do.
So Smirk is saying that our very slightly more congested traffic is a lot better than their constant road tripping.
As for MY feelings – I’d rather drive an hour than spend 15 minutes in a traffic jam.
Aah, I see now. So we spend less time in our cars, but proportionately more time in congestion.
The Portlander is in congestion 19% of her driving time, while the Nashvillian is in congestion 13% of her driving time.
So compact land use makes traffic congestion worse. (I know that’s a facile argument, but it’s about as much analysis as Cortright did.)
@ Reymont – Since when is spending more time in the car something that’s desirable? If you want to take an hour to get somewhere rather than 15 minutes, that’s a choice that I think few people would really make.
Compact land use also gives people choices in how they get around, something else the TTI doesn’t measure. Driving isn’t a must for every trip. The TTI doesn’t measure a lot of things, and a lot of people other than Cortright think it’s a flawed way to measure mobility. It only measures the mobility of cars, not people.
@w9q… – You’re comparing only the City of Portland with the Nashville Consolidated Area, which is comprised of the suburbs surrounding the city of Nashville. Compare it to the Portland Metro area as a whole, which is about 460 square miles.
Apples to apples, and all that.
Blabby, I like how you come into every thread about land use and insult people on the other side of the debate. He must not be an economist if he wants cities to grow in an efficient way, amirite?
The report counts delay per auto commuter. If you add in bus and MAX and bike and walking commuters, I bet the numbers look a lot better.
Dense development both enables and results from good transit service. Compact land use makes traffic congestion less of a problem at the same level. Think of two equally congested cities, but in one you have to go 2 miles to get to work and in the other you have to go 15.
Looking at the hard data in this report to find out about congestion is like looking at fuel tank capacity to figure out which car gets the best gas mileage. Yeah,the numbers might be accurate, but they’re not measuring what is actually important.
What’s the source of the average travel time data cited by Cortright and quoted by Sarah? It’s not in the report itself.
My fear is that the 193-hours-a-year figure only includes cars. A fair comparison of efficiency should include travel time among all modes. Maybe we’ve reduced the amount of time Portlanders spend sitting in cars but increased the amount of time people spend sitting on the MAX.
eldepeche, I comment on these posts because I am a land use planner by training who realized that it is 90% bullshit.
There is very very little behind our local land use cult. It is just a collection of mushy “sounds good to me” pseudo-analysis.
We “know” that our growth management and trains are working, but really we don’t know that at all. I encourage you to start digging into local land use “facts”. There is not much there there.
The blind worship of these ideas is what gets under my skin.
I wonder how may government there are in Nashville vs. Portland’s? Maybe in Nashville they drive more because they have JOBS.
Davidson County (Nashville metro) may be 500 square miles, but many people who work in Nashville drive in from surrounding counties. Sometimes they live over an hour away. Did the study include Rutherford, Williamson, etc counties?. As a resident of both towns, I can tell you, Nashville’s traffic is horrendous because you’re in a traffic jam and you still have 40 miles to your destination. Here you’re in traffic but you’ve only got 5 miles to go. Plus you have the option of biking/maxing/streetcarring/bussing/walking those miles. In Nashville you can only drive.
23rd worst?! You’re saying that like it’s a bad thing… there are 23 cities ahead of us that are worse off, and frankly I bet you any town lower than us on the list would not be, well, a metropolitan city. I’ll take Portland over Nashville any day, thank you.
I agree with Blabby. Cortright’s presentation on the CRC was horrible. His method of drawing a black box around the I-5 bridge to eliminate crash data on adjacent interchanges was a boldfaced obscuration of relevant data that was both unnecessary and self-defeating.
…that is, if he hadn’t been preaching to the anti-CRC choir.