Surface Transportation Innovations Newsletter

Surface Transportation Innovations #28

Topics include: Reason's new Mobility Project; occupancy detection for HOV/HOT lanes; more HOV lane concerns; truck-only toll lanes moving forward; and other news.

In this issue:

Mobility Project Takes on Urban Traffic Congestion

I am pleased to announce a major new Reason Foundation project. The Mobility Project is a multi-dimensional effort to rethink how America deals with urban traffic congestion. We have concluded that it is a far bigger and more damaging problem than is generally realized, but that it is not an inevitable part of urban America that we must learn to live with. In fact, the project aims to develop a set of policy recommendations to effectively remove traffic congestion as a serious problem for American cities.

We’ve assembled a large and distinguished research team, most of whom have been hard at work since last summer or fall on a whole series of research papers. Some explore the dimensions of our urban landscape and demographics, to explain why we (and our goods) travel so much-and will continue to do so. Others are looking at what has worked and what has not worked in reducing or alleviating congestion. Still others are looking at the planning, decision-making, and institutional arrangements that deal with transportation today, and how they might be changed and given somewhat different objectives. We are also doing a set of case studies, showing how our approach might be applied in a handful of specific urban areas of different sizes and types.

There will be a whole series of policy papers coming out this year from the Mobility Project, as well as a book distilling much of the project’s thinking into a form accessible to the intelligent general reader. A number of the project’s researchers will be making presentations at conferences around the country.

For more information, you can go to the Mobility Project’s new web site, at There you will find a project overview, a brief synopsis of each of the planned research papers, and a listing of the project’s distinguished Advisory Board. The web site will be updated regularly as the project proceeds—and I will also provide some highlights in future issues of this newsletter.

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New Technology for Occupancy Detection

In issue #22, I criticized then-current proposals to detect the number of persons in a vehicle (for determining HOV/HOT lane eligibility). Those proposals were based on in-vehicle technology (such as air bag sensors) and were therefore ridiculously expensive, having to be built into all new vehicles even though only a handful of them ever use HOV or HOT lanes. But now from Scotland comes a new approach which looks as if it might work well enough to use for HOV and HOT lanes.

Developed at the University of Loughborough, it’s based on looking through the windshield with both visible and near-infrared light detectors simultaneously. Tests on the U.K.’s first HOV lane (on A467 in Leeds) claim a 95% success rate in detecting real people and rejecting dummies. Apparently, the system is able to detect, uniquely, human skin. It is claimed to work under all weather conditions, but a recent article in Urban Transportation Monitor says that “although the infrared camera works well in bright sunlight, dull days and nighttime pose a challenge.”

It is now being tested for use in a new electronic toll collection/variable pricing system to be installed on the Forth Road Bridge in Scotland in 2007. That system, while charging peak and off-peak tolls, will also give discounts based on the number of occupants in the vehicle. The Forth Estuary Transport Authority is jointly funding the test with the Scottish government.

Lead researcher John Tyrer has formed a spin-off company, Vehicle Occupancy Ltd., to market a vehicle occupancy detection system called Cyclops, based on the technology. The UTM article above estimated that “an installation”—presumably outfitting one tolling location—costs an estimated $165,000. The company website is

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But Should We Continue with HOV Lanes?

Giving people incentives to carpool is the underlying rationale for HOV lanes (and for HOT lanes that let multi-occupant vehicles in for free or at a reduced toll). But growing evidence is accumulating that this policy is accomplishing less than many people believe.

In the recent Reason study on Virtual Exclusive Bus Lanes, my colleague Ted Balaker assembled considerable data on carpooling and HOV lanes. Among his findings:

  • Despite the quintupling of HOV lane-miles between 1990 and 2000, the fraction of commuters who carpool declined from 13.4% to 12.2%.
  • Between 33% and 75% of carpool members (depending on the city) are members of the same family, raising the question of how much real change in trip-making behavior the HOV lanes are bringing about.
  • Vehicle occupancy is lowest for work trips (and commuting is the focus of most ride-sharing efforts); every other category of trips has higher vehicle occupancy.
  • Vehicle occupancy is also lowest during commute hours; it’s significantly higher in the evenings and on weekends.

So the policy of promoting ride-sharing to ease peak-period congestion does not seem at all well-targeted.

But the most interesting new findings I’ve seen in quite awhile are in an article by Pravin Varaiya of UC Berkeley, in the Fall 2005 issue of Access titled “What We’ve Learned About Highway Congestion.” Varaiya has crunched mountains of data from the Caltrans PeMS (Performance Monitoring System) database of traffic on California freeways. Looking at data on HOV and general-purpose (GP) lanes on I-880, he concludes that HOV lanes increase congestion in two ways. First, by keeping non-HOV vehicles out of that reserved lane, the policy adds to congestion in the GP lanes. Second, in part since nearly all HOV facilities use a single lane in each direction, those lanes have less inherent capacity than regular freeway lanes, and hence operate almost as slowly as the GP lanes. He illustrates these effects with measurements of speed and flow on I-880 before, during, and after the peak periods when the HOV restrictions apply.

Interestingly, Varaiya also points out that every HOV lane in the Caltrans districts encompassing the San Francisco Bay Area, Orange County, and San Diego experiences “degraded conditions,” defined as speeds below 45 mph during peak hours for at least 18 days in a 180-day period. The new federal authorization to allow hybrid vehicles into HOV lanes does not allow this if the lanes operate under degraded conditions. Yet the political correctness of both hybrids and HOV lanes is so strong that Caltrans has asked the U.S. DOT for a waiver from this requirement!

We could get so much more real value out of these lanes if we re-purposed then as super-HOT lanes, usable only by paying vehicles (of whatever occupancy or engine type), emergency vehicles, and truly high-occupancy vehicles like vanpools and buses. And that way we wouldn’t need to count occupants, whether by hand or via new technology.

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Toll Truck Lanes on a Roll

Truck-only toll lanes continue to attract serious interest. Several months ago the Federal Highway Administration’s Public Roads magazine (Sept./Oct. 2005 issue) published an excellent survey article, “Issues in the Financing of Truck-Only Lanes.” Written by David Forkenbrock (University of Iowa) and Jim March (FHWA Office of Policy), it identifies and discusses the key issues that need to be addressed and identifies key research reports that have discussed aspects of the issue (including recent work from Reason).

There is a very useful discussion of the four potential benefits of such lanes to the trucking industry and the three potential benefits to passenger car operators. There is also a thoughtful discussion of who might pay how much—including reference to a paper I’d never heard of estimating Oregon drivers’ willingness to pay to not have triple-trailer rigs on the highways with them (estimated at $41/year in 2004 dollars). You can find this very worthwhile survey article at

I was also pleased to see three toll truck lane projects in the latest round of Value Pricing Pilot Program grant announcements. Georgia’s State Road & Tollway Authority, which sponsored the pioneering Atlanta TOT Lanes study I wrote about in issue #25, got two of the three grants: one to study implementation of TOT lanes on I-75 South and the other to study a Northwest Truck Tollway in Savannah. The other one went to Texas DOT to look into the feasibility of diverting trucks off of congested I-35 in Austin and onto the new SH 130 toll road.

Other exciting toll truck lane projects are being explored in several parts of the country, but are not yet ready for public discussion. I will report on others as it becomes possible to do so.

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Recommended Reading

Two excellent new books have crossed my desk in the last couple of months that I want to be sure you know about. Both concern the future of America’s highway infrastructure.

The first is actually a long booklet, but it’s packed with provocative thinking. “A Forum on the Future of Highway Transportation in America” provides detailed highlights from a day-long roundtable discussion on this subject convened by the International Bridge, Tunnel & Turnpike Association last July 27th. The 16 participants are some of the brightest and most thoughtful people involved with transportation, as you will see when you read this report. The discussion was divided into two parts: the challenges facing today’s highway system and a better vision of what it could be in this new century. There are so many provocative things in both parts of this discussion that it’s virtually impossible to single out one or two to quote here. And I’m pleased to note that even though I was unable to accept IBTTA’s invitation to be part of this discussion, many of Reason’s ideas were ably presented by others. Fortunately, IBTTA has the whole thing posted on their website, and you can find it at

The second is a new book from Heritage Foundation called 21st Century Highways: Innovative Solutions to America’s Transportation Needs, edited by my friends and colleagues Wendell Cox, Alan Pisarski, and Ron Utt. Ken Orski and I have a chapter in this one called “21st Century Toll Roads,” which includes a scenario for how we might evolve from today’s tax-funded system to one in which the limited-access system is both tolled and privatized. Other chapters cover the history of the federal highway program, performance-based transportation programs, devolution of some or all of the federal program to the states, and other topics. I want to especially call your attention to the chapter by Joel Schwartz of AEI on “The Social Benefits and Costs of the Automobile,” which provides a data-driven antidote to much of the conventional wisdom on this subject. The book is described on the Heritage web site ( and can be ordered there for $7.95.

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Updates from Last Issue

In my write-up of Reason colleague Ted Balaker’s new study on telecommuting, I made an error that many readers quickly spotted. I wrote that telecommuting’s mode share had increased by 23% between 1990 and 2000. Wrong. The number of telecommuters rose by that percentage, but the mode share increase was 10% (from 3.0% to 3.3%). Sorry about that!

The FHWA-sponsored synthesis report by Dan Dornan that documents and analyzes the global growth of public-private partnerships in transportation infrastructure is available on the web site of the National Council for Public Private Partnerships. You can find it at:

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Quotable Quotes

“I’ve seen, during my career, a sea change in the political acceptance of tolling. I don’t see us going back. . . . The time may be right to readdress how we fund transportation infrastructure in this country.”

-John Worthington, President, TransCore, ITS International, Sept./Oct. 2005.

“[A]s shippers, carriers, and others with a stake in national transportation infrastructure have rightly and loudly called for improvements in the country’s economic pipelines, the highway bill itself and the proverbial sausage-making process used to create it has become a caricature ill-serving the shipping community.”

-Paul Page, Editor, Traffic World, August 8, 2005.

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