Roads
Congestion report pushes sprawl through flawed analysis
The Texas Transportation Institute today released the final version of their report on congestion, which ranks the DC area tied for first with Chicago in hours wasted in traffic. Unfortunately, the report's methodology completely misleads as to the seriousness of traffic, and TTI is pushing the wrong policy solutions.
The TTI report narrowly looks at only one factor: how fast traffic moves. Consider two hypothetical cities. In Denseopolis, people live within 2 miles of work on average, but the roads are fairly clogged and drivers can only go about 20 miles per hour. However, it only takes an average of 6 minutes to get to work, which isn't bad.
On the other hand, in Sprawlville, people live about 30 miles from work on average, but there are lots and lots of fast-moving freeways, so people can drive 60 mph. That means it takes 30 minutes to get to work.
Which city is more congested? By TTI's methods, it's Denseopolis. But it's the people of Sprawlville who spend more time commuting, and thus have less time to be with their families and for recreation.
Sadly, despite CEOs for Cities pointing out these methodological problems last year, TTI went ahead and finalized its report without fixing them (PDFs). TTI ranks Portland as worse than Nashville, with a Travel Time Index (TTI) of 1.23 1.15 for Nashville and 1.15 1.23 for Portland. However, because of greater sprawl, Nashville commuters spend an average of 268 hours per year commuting, while the average Portland commuter spends 193 hours per year.
What does this mean for public policy and the Washington region? TTI's data is often used to justify spending money on new freeway capacity, since congestion sounds bad. TTI even promotes this approach. Tim Lomax, a co-author of the report, told the Post's Ashley Halsey III, "You can do little things like stagger work hours, fix traffic-light timing and clear wrecks faster, but in the end, there's a need for more capacity."
"That we are congested is not news, but TTI's report does tremendous damage, because they fail to recognize the primary cause of our congestion and imply that we could simply widen roads to build our way out of the problem," said Stewart Schwartz, Executive Director of the Coalition for Smarter Growth.
What Lomax didn't say, and which Halsey didn't print even though he should know better, is that there are other approaches besides those "little things." What you can do is concentrate future growth around existing hubs with more residents, jobs, and multimodal transportation.
That's what the Metropolitan Washington Council of Governments (COG) is trying to push with its Region Forward plan and the related "What Would It Take?" scenario (PDF). These involve focusing development in places like Tysons Corner and the Route 1 corridor in Fairfax, around underutilized Metro stations in Prince George's, future ones in Loudoun, and MARC and VRE hubs in Maryland and Virginia.
Arlington achieved substantial job and resident growth in its Rosslyn-Ballston corridor without adding to traffic congestion, as has Montgomery with growth in Silver Spring and Bethesda and DC development in places like NoMA and the Capitol Riverfront area. Regional leaders should be less concerned with speeding up existing cars, which just leads to sprawl farther out, and invest more in finding ways to grow the region without adding traffic.
In fact, that's just what the DC region has done. Another, better part of TTI's analysis measures the amount of time savings that come from each region's transit; DC is 3rd best. That metric still doesn't account for the value of people living nearer to their jobs, however.
Between better location and transit, to page 50, congestion has not increased since 1999 even on TTI's flawed scale. That means our region has been successfully growing without adding traffic. Instead of "Washington area tied with Chicago for traffic congestion, study finds," this morning's Post headline this morning could have read, "Washington area's traffic hasn't gotten worse in a decade thanks to smart growth."
It's more than a little baffling, though, that Halsey didn't make any reference to the CEOs for Cities report or the COG work. He also wrote, "Researchers said the depth of the data used in this year's study far surpassed the quality of information used in past years, giving the results an unprecedented degree of accuracy."
So, the researchers at this supposedly very highly regarded institute say that their data is super great, but they and the reporters ignored the widely-publicized critiques of their methodology. Maybe it's time for TTI to stop being so highly regarded.
Comments
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A few pushbacks:
1. I said this AM that we have two Washington: one very road dependent, the other less so. I'd actually say three: WMATA DC, freeway DC, and suburban DC. I know plenty of people who live in Fairfax and use the freeway for one exit, or don't use it at all. Plenty of others works in MD and drive to VA everyday.
Is development the low-cost fruit? Stop charging so much for long distance metro and parking? More commuter rail? I'm not sure.
Development DOES work -- as Arlington shows, or parts of Mont. County -- but not sure if it scalable. Tysons, for instance.
2. Too much focus on commutes. What really kills you, driving, in the suburbs is errand run day. And schools. Commute driving focus on a few key choke points, which are then overbuilt to deal with the traffic. I'd rather look at development and find ways to shave 2-3 miles off. (Wegmans, despite being a car mecca, is a pretty good example of that).
by charlie on Jan 20, 2011 3:26 pm • link • report
The paragraph in this blog post about Arlington's growth along Wilson Boulevard makes a good point, though, and you can very easily compare Arlington's planning with Fairfax County's. I assume many folks here have read Zachary Schrag's book on the history of the DC Metro system. His discussion of Fairfax County's dithering about the Metrorail back in the 1960s, and about their fear of allowing development near the stops, is really damning. The Dunn Loring stop is finally seeing some development, but they utterly dropped the ball when it came to the Vienna stop in particular. (I think Franconia-Springfield has some wetlands issues that prevent too much development, so I suppose they get a pass on that one.) Arlington grafted growth onto the transit lines. Fairfax let growth happen and is now trying to graft a transit line (rail through Tysons) onto that growth, which seldom works nearly as well.
by Rich on Jan 20, 2011 3:37 pm • link • report
by David Alpert on Jan 20, 2011 3:45 pm • link • report
WTOP, for example, reported on the story, but also noted that the region is 3rd in reducing delay thru public transportation. That's one part of the report that you completely left out.
by Froggie on Jan 20, 2011 3:57 pm • link • report
by Steve D on Jan 20, 2011 4:05 pm • link • report
#2. The problem with the CEOs for Cities report is that they basically only used their analysis to bash the TTI and didn't use it to try to promote anything positive. "Sprawl is the problem and the TTI doesn't measure that" - well we know that! Their only answer to the sprawl problem seemed to be an implied suggestion that people should live differently, without any sort of discussion on HOW you make people do that.
It's said time and again here that the reason people live in sprawlville is because we enable them to live in sprawlville through massive road building. So if you want to create a report that says sprawl is the problem, then come up with some solutions like more transit service, more development in urban settings, etc. Just saying "sprawl is bad and makes peoples' commutes longer" isn't going to get anybody to move.
by MLD on Jan 20, 2011 4:54 pm • link • report
by Tim on Jan 20, 2011 5:18 pm • link • report
by David Alpert on Jan 20, 2011 5:41 pm • link • report
Our transportation system is a balance between the modes used by different groups: pedestrians, bicyclists, rail and bus riders, drivers and passengers. Each mode has a role, some more, some less depending on a community's consensus. To suggest the report has one answer doesn't answer the question. Maybe you should contact Mr. Lomax for his perspective to DC's issues, that would lead to some insightful dialogue instead of an anti-highway screed.
by Some Ideas on Jan 20, 2011 7:33 pm • link • report
Actually, at least as far back as 1999, I've been reading in the Post that the Washington Metro area was 2nd worst. However, LA was always cited at 1st worst in the past. Did Chicago and LA somehow switch rankings? Or is this a different study than the one the Post quotes annually. I guess it points to the fact that you can find a statistic to back up whatever point you're trying to make.
by Lance on Jan 20, 2011 10:37 pm • link • report
"Good reporting not just tells people that a particular report is out but also informs people about various points of view that inform thinking about it."
The writers on this site, David included, also often fail to do this. Opposing viewpoints are rarely, if ever, presented, and then only in mocking terms.
Pot, meet kettle.
by Anon on Jan 20, 2011 10:39 pm • link • report
by William on Jan 20, 2011 11:09 pm • link • report
http://mobility.tamu.edu/ums/congestion_data/tables/national/table_8.pdf
compared to Table 1, pg 22 of this years report here: http://tti.tamu.edu/documents/mobility_report_2010.pdf
Example to consider related to my earlier question -- Seattle has moved a 0.10 lower in the index -- what changed in the data to drive that number? Then in turn what lessons can we glean for the Washington Metro area?
by Some Ideas on Jan 21, 2011 3:35 am • link • report
GWW continues to earn that respect by seeking out and reporting on information that is relevant and of interest to a wide enough section of folks and by starting important conversations about policy issues that make a difference in the lives of just about everyone. But there are definitely more than a few clunker posts here by folks with a point to make and who seem unaware of any broader responsibility to fairness, truth, rhetoric, etc. I'd lay the blame for that firmly in David Alpert's lap - it's his site and so his responsibility to establish the standards for those who are allowed to write here.
Because of the subject matter and breadth of coverage, it's still one of the first blogs I check on a daily basis but I definitely find myself wincing from time to time at the immaturity and simplicity of some of the writing.
by Josh S on Jan 21, 2011 8:50 am • link • report
Journalistic news articles are supposed to provide readers with different valid points of view.
And you can thank Fox News for blurring the line between opinion and news so much that now we have to explain to people what the difference is.
by MLD on Jan 21, 2011 9:08 am • link • report
by Frog on Jan 21, 2011 10:21 am • link • report
by KadeKo on Jan 21, 2011 1:04 pm • link • report
by Johne37179 on Jan 21, 2011 1:43 pm • link • report
I don't want to sound like I'm flat-out defending Ashley Halsey. I remember when he used to contribute to Dr. Gridlock's blog and a lot of complaints were made because his postings tended to be sloppy and hard to read (the thing I most recall is that he never put a blank line between paragraphs). To the extent the editors want a certain thing, though, it's not necessarily his "fault" that he didn't critique the report. There's a fair chance that critiquing it wasn't part of his assignment, and there's also a very good chance that if he were to go beyond his assignment (I do not know whether he would, mind you), the editors might cut it. Newspapers tend to lay out their pages prior to the stories being handed in, and the reporters either have to write their stories to fit the space or see the stories cut down.
by Rich on Jan 21, 2011 3:09 pm • link • report
That is hardly necessarily true regarding the Washington Post:
http://wwwtripwithinthebeltway.blogspot.com/2007/01/washington-post-lies-about-inside.html
And such error comes along with more error correlated to a bias:
http://wwwtripwithinthebeltway.blogspot.com/search/label/Washington%20Post%20Lying
by Douglas Willinger on Sep 22, 2011 6:15 pm • link • report
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