Surface Transportation Innovations Newsletter

Surface Transportation Innovations #36

Topics include: Reason's new book on congestion; driving restrictions and air quality; the latest update from the guru of commuting data; two very different models of managed lanes; and other news.

In this issue:

New Book Explains Congestion to Non-Experts

Those of us who spend our full-time efforts on transportation often despair that the average voter, the average reporter or editorial writer, or the average legislator doesn’t know what we know. If only they did, we believe, many more of them would support concepts like value pricing, HOT Networks, design-build, long-term concessions, etc. So I’m especially pleased to tell you that two of my Reason colleagues, Ted Balaker and Sam Staley, have written a serious but very accessible book about traffic congestion and what we can do about it. The Road More Traveled (Rowman & Littlefield) was released several weeks ago, and is available from Amazon, among other book sellers.

In many respects, this is a book I wish I had written (though other time commitments made that impossible-and these guys are better writers in any case). But I was certainly involved in helping Ted and Sam think through the issues, and I reviewed and critiqued chapter drafts and then the final manuscript. As a product of Reason’s Galvin Mobility Project, it also had the benefit of inputs from the project’s distinguished Advisory Board (see

One of the book’s real strengths is its thoughtful discussion of how much mobility matters, both to people and to urban areas—and therefore how costly (not just in dollars) congestion really is. A lot of research on these issues is being done as part of the Mobility Project, and Ted and Sam draw on that in these chapters. I’m also partial to the chapters explaining why so much of what passes for conventional wisdom in transportation planning these days is “things that everybody knows that just ain’t so.” But the real payoff comes in the book’s last five chapters, in which the authors draw on lessons from here and abroad to lay out a bold approach for attacking and dramatically reducing congestion, thereby increasing urban mobility and restoring vitality to impacted urban areas. It will not surprise you, as a reader of this newsletter, to learn that this approach leans heavily on pricing, technology, and new construction.

The book carries impressive endorsements, including one from Mary Peters, before her recent appointment as Secretary of Transportation. Let me leave you with a quote from Joel Kotkin: “The Road More Traveled should be required reading not only for planners and their students, but also for anyone who loves cities and wants them to thrive as real places, not merely as museums, in the twenty-first century.”

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Driving Restrictions and Air Quality

Mexico City pioneered the approach of restricting car usage in order to reduce vehicle-caused air pollution, an approach subsequently emulated in Bogota, Santiago, and Sao Paulo (and sometimes proposed in this country). Implemented in 1989, Mexico City’s “Hoy No Circula” (HCN) bans all vehicles with a specific last digit on their license plate from driving one weekday per week. It is evidently well-enforced, and has definitely kept most of the targeted vehicles off the roads one day out of five. But has it improved air quality?

That question is examined in some detail in a new paper by economist Lucas W. Davis of the University of Michigan (“The Effect of Driving Restrictions on Air Quality in Mexico City,” available at Lucas used extensive data from the metro area’s network of emission-monitoring stations to compare the levels of five criteria pollutants before and after HCN went into effect. He finds no direct reductions in any of the pollutants due to HCN. A sharp decline in sulfur dioxide after 1992 is likely due to dramatic reductions in the sulfur content of diesel fuel in the early 1990s.

This finding raises several important questions, which Lucas goes on to explore. First, why didn’t HCN do what it was intended to do? It apparently did cause some shifting of trips by owners of the restricted vehicles to late night or very early morning travel (outside the ban), but those trips (while lessening peak congestion) still polluted the air. There was also an increase in emissions on weekends, as people made trips then that they could not make on their driving-ban day. What did not happen was a shift by drivers of those vehicles to subway or bus on the days when they could not drive. In fact, both bus and subway lost mode share in the years following implementation of HCN. What most drivers did turn to was taxicabs. Lucas finds evidence of a sharp increase in demand for taxis in the Mexico City market during 1990-93. And from data on the average age and condition of typical cabs, “taxis during this period were likely to be among the highest-emitting vehicles in Mexico City.”

Since HCN did not do what it was intended to do, and indeed, appears to have made air pollution worse in its early years, what should Mexico City (and others like it) do now? It turns out that in 1994, Mexico did what it should have done in the first place: it adopted U.S. emission standards for all new vehicles. While this change will take several decades to have its full effect (thanks to fleet turnover), it is probably the most cost-effective approach.

The Mexico City experience is another reminder that even in a far less-affluent society than ours, the enormous benefits of personal mobility led to massive resistance to the attempt to shift people’s behavior away from door-to-door transportation at the time of their choosing.

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Commuting in America, Mark III

Every 10 years the U.S. Census develops detailed data on how Americans commute. And like clockwork, Alan Pisarski crunches the numbers and produces the definitive interpretation of what it all means. Commuting in America III was released earlier this month by the Transportation Research Board. My copy has not arrived yet, but I can give you a preview, based on some tidbits that Alan shared with me.

First, he concludes that we are in a time of transition, with new factors shaping the American commute. The baby boom generation is on the verge of retirement age, but no one knows how many will actually “retire” and how many will continue working, either with a daily commute or by telecommuting. The large entry of women into the labor force has pretty much topped out. African-Americans are rapidly increasing their vehicle ownership, becoming more like the rest of America. And the immigrant population seems to begin as heavy transit users, migrate to car-pooling, and only gradually adopt the individual automobile as their commuting mode of choice.

Second, the changes in modes of commuting between 1990 and 2000 were pretty small, by and large reinforcing the significant changes from 1980 and before. The single occupant vehicle gained about 11 percentage points over the 20-year period, while car-pooling dropped from 20% of all commute trips in 1980 to about 12% in 2000. But for the first time in 2000, drive-alone shares decreased slightly in five metro areas (all in the West). Most carpooling and transit shares changed little from 1990 to 2000. Interestingly, while about 32% of all commuting takes place in areas with more than 4,000 persons per square mile, 80% of transit use occurs in such areas (which should not be surprising).

In terms of commuter travel times, congestion is taking its toll. The national average commute took 21.7 minutes in 1980, 22.4 minutes in 1990 and 25.5 minutes in 2000. Despite congestion, driving alone is still the fastest, door-to-door (which is what counts), with commuter rail the longest. Average transit travel times are about double the time of driving alone.

But the shortest commutes of all are for telecommuters like me. As Alan notes, telecommuting is the only commuter mode besides driving alone that increased its mode share over both decades. And it will be a key factor in the commuting impact of the growing over-65 population in coming decades. As of now, telecommuters are mostly either younger women in service occupations or older men in professional activities.

Commuting in America III will be the standard reference work on the subject for the next decade, just as its predecessors have been. You can order your copy from

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What Kind of Managed Lanes?

On a number of occasions this year I have given a presentation before transportation groups contrasting two different models for priced managed lanes (whether called HOT lanes or something else. Model 1, as I call it, conceives of the lanes essentially as HOV lanes that sell any excess capacity to paying customers. Their purpose is to maximize ride-sharing, helping to meet the goal of reducing peak-period driving. Model 2, by contrast, conceives of the lanes as congestion-relievers, offering fast, reliable, trips to paying customers, and as incidentally assisting in various transit and ride-sharing goals (e.g., by letting buses and vanpools use the lanes at no charge). California’s two pioneering projects serve as role models. The I-15 HOT lanes in San Diego are a classic Model 1 project, with all net toll revenues dedicated to subsidizing commuter bus service in the corridor. The 91 Express Lanes in Orange County are a classic Model 2 project, offering half-price rates to HOV-3 vehicles but no other freebies.

The differences I summarized may not sound like much, but they make an enormous difference. Model 1 projects, because they give top priority to car-pooling, generally let as many HOV-2s as possible use the lanes, even to the point of excluding any paying customers. That’s just what happens in some of the HOT lane feasibility studies I’ve reviewed for several large metro areas recently: precisely at the busiest peak periods, when congestion relief is needed most and people are willing to pay the highest price, the lanes are shown as generating zero revenue, because demand for HOV-2s must be accommodated.

It’s this kind of nonsense that leads some to conclude that “HOT lanes can only generate enough revenue to pay for operating and maintenance costs, not for capital costs.” And because building a network of HOT lanes in a large congested urban area would be a multi-billion-dollar effort, it’s clear that as long as Model 1 prevails, we aren’t going to see anything like HOT networks get built. Whereas, we already know that the Model 2 approach in Orange County is paying the entire capital cost of those four new lanes, as will the Model 2 approach being planned for the Washington, DC-area Beltway HOT lanes.

I’m pleased to report that the Dallas/Fort Worth metro area has recently adopted a largely Model 2 approach. The North Central Texas Council of Governments developed the draft policy and engaged public and private-sector stakeholders in debate and discussion earlier this year (including a presentation by me in Ft. Worth). You can download the resulting “Managed Lane Policies” by going to and clicking first on Regional Transportation Council, then Toll Policies, and then Managed Lanes Policy. The same approach will be used for all managed lanes in the metro area. Each ew managed lane will begin with a six-month introductory phase, during which it will operate with a fixed toll rate of up to 75 cents/mile, adjusted monthly. After those initial six months, the pricing will be dynamic (as in San Diego), at whatever rate is needed to manage traffic flow with a minimum average corridor speed of 50 mph. Transit vehicles will go free, and HOV-2s will get a 50% discount during peak hours but pay the full rate other times. The HOV discount will phase out after the region has demonstrated attainment of air-quality goals; at that point, the lanes will become pure Express Toll Lanes (i.e., Model 2).

Several other details are worth noting. Once the system goes to dynamic (market-based) pricing, drivers will receive rebates if the average speed drops below 35 mph. And there will be no discounts for “green” vehicles—a proper distinction between transportation finance policy and environmental/energy policy. It’s contemplated that many of these managed lanes will be developed and operated by the private sector under long-term partnership or concession agreements. The policy recognizes that the length of such agreements should permit developers to maximize their potential revenue. It also acknowledges that pricing will be essential to sustain the performance of the lanes, so that “tolls will remain on the managed lanes” after the PPP agreement terminates.

This is one of the best managed lanes policy statements I’ve seen. Other Metropolitan Planning Organizations that are looking into HOT lanes and HOT networks should take a careful look at this policy.

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Speaking Engagements Update

  • I was scheduled to be on a panel at Bond Buyer’s transportation finance conference in Houston, Oct. 19th, but then got invited to make a presentation to the National Surface Transportation Policy and Revenue Study Commission on that very same day in Washington, DC. Needless to say, I’m doing the latter; many thanks to friend and colleague Dan Dornan for filling in for me on short notice at the Bond Buyer conference.
  • On Monday, Oct. 23 I will be speaking at two events in Honolulu. The first is a breakfast forum on transportation, hosted by the Hawaii Chamber of Commerce. The second is a transportation forum sponsored by the Hawaii Highway Users Alliance.
  • I will be in New York on Oct. 26, speaking at the Strategic Research Institute’s conference on “Infrastructure: A Growing Asset Class.” This takes place at the Marriott Marquis Hotel.
  • Although I’m not speaking at it this year, I will be attending the Public-Private Ventures conference of the American Road & Transportation Builders Association in Washington, DC Nov. 16-17; this is always an excellent event.
  • On Nov. 29 I will be speaking at the Greater Miami Chamber of Commerce’s Transportation Summit.
  • And on Dec. 5 I am chairing a panel on truck toll lanes at the International Bridge, Tunnel, and Turnpike Association’s Transportation Finance Summit in Washington, DC.

I hope to see you at one or more of these events.

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Robert Poole is director of transportation policy and Searle Freedom Trust Transportation Fellow at Reason Foundation. Poole, an MIT-trained engineer, has advised the Ronald Reagan, the George H.W. Bush, the Clinton, and the George W. Bush administrations.