Sunday, September 03, 2006

Reason calculates the cost of congestion relief

Last week, the Reason Foundation released a major report on traffic congestion trends in America and what it would cost to fix it. Here's the overview from Bob Poole's Surface Transportation Innovations newsletter:

Adding Capacity is Key to Cutting Congestion, New Study Says

Every year the Texas Transportation Institute’s Urban Mobility Report has a little section that shows, with real numbers, that those urban areas which came the closest to keeping highway capacity growing in pace with vehicle miles traveled (VMT) had the smallest increases in congestion. But more and more of America’s metropolitan planning organizations (MPOs) have been ignoring this point. In a new Reason Foundation study, David Hartgen and Greg Fields of University of North Carolina at Charlotte show that the long-range transportation plans of many urban areas downplay highway expansion, devoting well over half their total planned spending over the next 25 years to non-highway aspects of transportation ( This is true not just in those places with traditional central business districts where transit can play a meaningful role (e.g., New York, Chicago, Boston) but also in large suburbanized areas such as San Jose, Salt Lake City, Charlotte, and San Diego, where transit can serve only niche markets.

What’s happened over the past two decades is the triumph of the idea that “we can’t build our way out of congestion,” and hence that the only sensible policy is demand reduction. That accounts for the tremendous shift of resources from highways to transit, bike paths, and smart growth. The idea is that by dramatically reducing demand (VMT), we can thereby reduce congestion. Except that somewhere along the line, many of these same MPOs seem also to have lost sight of reducing congestion. As Hartgen and Fields note, in many long-range plans this no longer appears even as a goal. And if the plan’s authors are honest enough to include their projected conditions in 2030, most show that congestion will be even worse than today’s intolerable levels.

What this new study sets out to do, then, is to ask and answer the question: What if we wanted to expand highway capacity in response to the demand that’s clearly there? More specifically, Hartgen and Fields worked with 32 MPOs to run their traffic assignment models so as to answer the question: How many lane-miles would you need to have, by 2030, to eliminate all serious congestion (defined as Level of Service F)? And then, using generic cost data for various types of lane-miles (freeway, major arterial, etc.), they estimated what it would cost to add this capacity over the next 25 years. Finally, using some rather clever techniques, they extrapolated these results to all 403 urbanized areas in the United States.

The resulting numbers look big at first glance: 104,000 added lane-miles costing $533 billion in 2005 dollars. But they aren’t really that large when put in perspective. That cost of $21 billion per year is about 10 to 15% of already planned highway spending. It’s about 28% of current MPOs’ long-range transportation budgets. Thus, if none of the existing budget allowed for highway capacity expansion, the worst-case spending increase would be 28%. But in fact, most of these plans include some highway capacity additions, especially HOV lanes. And most of them include large sums that do little or nothing to reduce congestion, which conceivably could be shifted to capacity expansion, so the net cost increase might be zero.

What about the benefits? Hartgen and Fields estimate (based on the modeling results) that by 2030, nationwide travel time savings would be 7.7 billion hours per year. The cost of producing those savings varies considerably from city to city, ranging from as little as 9 cents per trip to about 75 cents per trip (in large cities). Overall, the average cost per hour saved is $2.76, far below even very conservative estimates of the average value of people’s time.

To be sure, we know that incident-related congestion amounts to about half of total congestion, so adding capacity is not the only solution. But this paper makes a solid case that it can be a major part of the solution.

This paper is the first in a whole series of studies to be published by Reason over the coming year, as part of our Mobility Project ( Forthcoming papers will address topics such as the full economic and social cost of high levels of congestion, the best ways to use road pricing to reduce congestion, innovative design ideas for adding capacity, the role of transit in reducing congestion, and many related issues.

There's some mostly good news for Houston in this report. The first is that we're not in this list:
How bad is your commute going to get? Twenty-five years from now, Los Angeles, home to the nation's worst traffic today, will still have the nation's worst delays, with a trip during peak hours taking nearly twice as long as it would during off-peak times.

But by 2030, drivers in 11 other major cities – Atlanta, Baltimore, Chicago, Denver, Las Vegas, Miami, Minneapolis/St. Paul, Portland, San Francisco-Oakland, Seattle-Tacoma, and Washington, D.C. - will all be sitting in daily traffic jams worse than the infamous traffic jams that plague Los Angeles today, according to a Reason Foundation study.
Here are the Houston specifics:

Houston's Travel Time Index (TTI) is expected to rise from 1.42 to 1.61 by 2030 (Texas' stated goal is 1.18). This means that in 2030, travel times during peak traffic hours will be 61 percent longer than during off-peak times. Such congested conditions are seen today only in Los Angeles, the most congested city in the United States.

Houston could significantly reduce severe congestion and have room for the incoming population growth by adding 2,660 new lane-miles by 2030 at an estimated cost of $9.2 billion, in today's dollars. That's a cost of $111 per resident each year. This investment would save 134 million hours each year that residents currently lose sitting in traffic, at a cost of $2.74 per delay-hour saved. (a bargain, IMHO)

While $9.2 billion may sound like an exceedingly large investment, it is actually just 12 percent of the planned transportation spending under the Houston-Galveston Area Council (H-GAC) long-range plans. (H-GAC is the regional Metropolitan Planning Organization, or MPO.) Those plans call for $77.3 billion over the next 25 years—$46.7 billion on highway improvements, $17.9 billion on mass transit, and $12.7 billion on other projects. While about 3.3 percent of Houston area commuters now use mass transit to commute, transit accounts for 23 percent of the area's planned spending over the next 25 years. While some of the planned highway improvement funding may be used for capacity expansion, the majority is often allocated to preserving, maintaining, and operating the highway system.

That projected 1.61 congestion index (ratio of peak travel times to off-peak) is still only 23rd in the nation (cool Google ranking map). Not bad for what will probably be one of the five largest metros nationally in 2030. Almost all other large metros are in much worse shape than we are, including DFW with a TTI of 1.73, which they calculate needs over $26 billion for the same relief as our $9.2B. Of the top 15 metros, only Seattle and Minneapolis need less money than Houston.

I do have some quibbles with their population numbers for Houston, which are based on something called "urbanized area" - a definition I'm not familiar with. It shows us with only 2.6m today growing to almost 4m by 2030. Today's stats are roughly 2.1m in the city, 3.5m in the county, and 5.3m in the metro, with 3m more by 2030 for a total of 8+ million - more than double their numbers. The nice side of that discrepancy is it cuts that cost per resident per year number in half, to less than $56.

They don't say this, but I suspect that the reason Houston is in so much better shape than most other metros is we never abandoned or slashed highway capacity expansion plans as many have, and they've fallen into a much deeper hole as a result. We've also stayed more realistic about what transit can and can't do, and invested in more cost-effective transit solutions (like HOV express buses, vanpools, and carpools instead of commuter rail). Here's to staying the course.


At 2:02 PM, September 05, 2006, Anonymous Anonymous said...

This is possibly slightly off topic, but I've always been puzzled by the idea that when new road capacity fills up it is somehow a failure and thus shouldn't have been built in the first place. If the goal of any transportation system is "mobility", that can still go way up even if "congestion" doesn't go down.


At 2:43 PM, September 05, 2006, Blogger Tory Gattis said...

Agreed. To quote from one of my old op-eds on the Katy freeway expansion:

Let’s start with the “common wisdom” that new freeway lanes just get filled up with new congestion, leaving nobody better off. While new capacity does create “induced demand”, adequate freeway capacity can confine congestion to narrow windows during rush hour as opposed to the all-day congestion currently occurring on the Katy Freeway - just ask 59 Eastex commuters if they’d rather go back to its pre-widened days. What’s invisible is that all that capacity allows tens or hundreds of thousands of people to live in better and cheaper homes while staying within a reasonable commute to work. Studies have shown that people typically buy the best value housing they can within about a 30-45 minute one-way commute to their job, and more freeway capacity gives more people more options. Houston has been able to maintain some of the lowest major-city housing costs in the nation through a combination of aggressive freeway capacity expansion and no zoning.

At 2:48 PM, September 05, 2006, Anonymous Anonymous said...

I found the article to be a huge load of bull...We Simply can't continue to build ourselves out of this mess...

Here's my full view:

At 3:15 PM, September 05, 2006, Blogger Tory Gattis said...

Read your post, and I disagree. While a commuter line has the *potential* to move 50,000/hour, most move far, far less - usually less than one car lane's worth, at much higher cost. Your best bet are high-occupancy express toll lanes that can offer any commuter bus/van/carpool 65+ mph express point-to-point service from any suburb to any business/jobs center. Trying to concentrate jobs a la Chicago or NYC is a lost cause - employers will gravitate to cheaper office space more easily accessible by their employees with more affordable housing. "Build rail and the jobs will come downtown" has not worked for Atlanta, Dallas, or LA. Only DC has pulled it off in recent history, and that's because the feds dictate the jobs will be in downtown DC.

At 1:42 PM, September 08, 2006, Anonymous Anonymous said...

I agree with the premise: we can build ourselves out of congestion (or almost anything for that matter if we devote the resources, and have the patience and political will to do so). However, I question their population numbers for Houston as you do, Tory. I think the "urban area" definition has something to do with FIPS (see

The data they have presented seems to agree pretty reasonably with the following source (which also uses the urban agglomeration definition):
(Click on City Population, then click on United States of America, then click Display)

For the first 22 cities in the congestion report, there seems to be reasonable agreement (considering that the congestion report uses 2003 estimates while the UN data is for 2000 and 2005) except for Atlanta (2,924,000 vs. 4,304,000) and Houston (2,620,000 vs. 4,320,000).

These two points aren't essential to their thesis, but it strains their credibility when they are this far off for these two very car-dependent metro areas.

I enjoy your posts. Keep up the good work.


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