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Posts from the VMT Category


Planning for Less Driving, Not More, Would Lead to Big Savings


Chart: MassPIRG

What if, instead of basing policy around the presumption that people will drive more every year, transportation agencies started making decisions to reduce the volume of driving? And what if they succeed?

A new report from the Massachusetts Public Interest Research Group quantifies what would happen in that state if driving rates come in one percentage point lower than the state DOT’s current annual projections. For instance, in a year that the DOT forecasts 0.49 percent growth in driving, MassPIRG hypothesizes a 0.51 percent decrease. MassPIRG estimates that the statewide effect from now until 2030 would add up to about $20 billion in savings and 23 million metric tons of carbon emissions avoided.

The effects grow as the decline compounds over time. In the first year, a one percentage point change in driving rates would save about $167 million in avoided costs of gas, road repairs, and traffic collisions. By 2030, the savings would rise to $2.3 billion per year.

Broken down by category, the state would save about $1.9 billion on road repairs over the 15-year period. Drivers would net $3.8 billion in savings on car repairs and another $7.7 billion on gas purchases. And auto collisions would cost $6.7 billion less to society, as people avoid medical expenses, property damage, and lost wages.

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Why Creating Meaningful Transportation Change Is So Hard

Cross-posted from City Observatory.

At his blog, The Transport Politic, Yonah Freemark pushed back this week on the idea that we’re seeing a revolution in the way people get around cities and suburbs, largely thanks to new transit-and-bike-friendly Millennials.

In fact, he cites one of City Observatory’s posts as an example of a narrative he doesn’t think is quite right: that despite an uptick in driving as a result of dramatically cheaper gas prices, economic and preference-based fundamentals suggest that we are still in the midst of a historic decline in driving after generations of consistently rising car dependence.

Freemark, who also works at Chicago’s Metropolitan Planning Council, is an excellent commentator on transportation and urban development, and we are all very much on the same page in believing in diverse, inclusive cities whose transportation systems contribute to walkable, integrated, sustainable neighborhoods.

Moreover, the central point of his post is not just correct, but hugely important for all transit advocates and urbanists to understand. As we’ve written, changing preferences are not enough to change transportation behavior, because a person’s behavior heavily depends on their options. Those options, in turn, depend on available transit services and land use patterns.

If the only available public transit is a very slow bus that comes once every 30 minutes—or the only bike route is along a high-speed stroad without a bike lane — it’s likely that even the most car-hating Millennial will get behind the wheel to get to work. Land use is similarly important: if your job isn’t anywhere near a transit station, it’s extremely unlikely you’ll be able to avoid driving, even if you’d really like to. In effect, land use patterns lock in place the mode choice preferences of previous generations and changes in behavior can happen only slowly. We can’t have a transportation revolution without major improvements to transit services and road design, and major reforms to our land use laws.

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The End of Peak Driving?

Cross-posted from City Observatory

A little over a year ago, a gallon of regular gasoline cost $3.70. Since then, that price has plummeted, and remains more than a dollar cheaper than it was through most of 2014.

Over the same period, there’s been a small but noticeable uptick in driving in the US. After nearly a decade of steady declines in vehicle miles traveled per person, car use has suddenly pushed upwards. Average miles traveled per person, which were 25.7 a year ago, have jumped up to 26.4 in July—the first sustained increase in driving in more than a decade.

Some in the highway community have heralded the growth in driving in recent months as a sign that we need to invest much more in road construction.

The increase isn’t very big, however. In historic terms, Americans are now driving at about the same rate as they were in 2000. It would take nearly a decade of growth at the current rate of expansion just to get back to the level of driving of 2004. But there’s little reason to believe anything like that is in the cards.

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Without Transit, American Cities Would Take Up 37 Percent More Space

Even if you never set foot on a bus or a train, chances are transit is saving you time and money. The most obvious reason is that transit keeps cars off the road, but the full explanation is both less intuitive and more profound: Transit shrinks distances between destinations, putting everything within closer reach.

A new study published by the Transportation Research Board quantifies the spatial impact of transit in new ways [PDF]. Without transit, the researchers found, American cities would take up 37 percent more space.

Transit-oriented development in Portland's Pearl District. Photo:

Transit-oriented development in Portland’s Pearl District. Photo:

The research team from New York, San Francisco, and Salt Lake City modeled not just how many driving miles are directly averted by people riding transit, but how the availability of transit affects the way we build cities.

By allowing urban areas to be built more compactly, the “land use effect” of transit reduces driving much more than the substitution of car trips with transit trips. Total miles driven in American cities would be 8 percent higher without the land use effect of transit, the researchers concluded, compared to 2 percent higher if you forced everyone who rides transit to drive.

On average, the study found, the “land use effect” of transit is four times greater than the “ridership effect,” or the substitution of car trips with transit trips. But the land use effect of transit varies a great deal across urban areas, the study found. In places like Greenville, South Carolina, it’s responsible for reducing driving 3 percent. In San Francisco and New York City, it’s 18 and 19 percent, respectively.

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FHWA Gleefully Reports That Driving Is Rising Again

Chart: Doug Short

Chart: Doug Short

After flatlining for nearly a decade, the mileage driven by Americans is rising once again. That means more traffic overwhelming city streets, slowing down buses, and spewing pollutants into the air. But to the Federal Highway Administration, it’s a development to report with barely contained glee.

This June, Americans drove 8.7 billion more miles than last June, according to FHWA, a 3.5 percent increase. Total mileage in 2015 is on pace for a new high — finally “beating the previous record” of 1.5 trillion vehicle miles set 2007, the agency reports, as if the further entrenchment of America’s car-dependence is some sort of achievement.

Low gas prices, population growth, and an expanding economy are three factors nudging traffic back onto an upward trajectory, not to mention a transportation policy regime that remains tilted overwhelmingly toward highway construction.

The recent growth in traffic, however, does not negate lasting signs of a long-term shift away from driving. Economist Doug Short gets into more detail about the nuances in the trends, pointing out that on a per-capita basis, Americans are now driving about as much as we did in 1997.

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Putting the Recent Uptick in Driving in Perspective

Driving is on its way up again after a decade of stagnation, but it's still not what it was. Graph: Federal Highway Administration

Total driving mileage has risen recently after a decade of stagnation but remains below its 2007 peak. Graph: Federal Highway Administration

With gas prices plummeting and employment figures rising, America’s per capita driving rate increased in 2014 for the first time in nearly a decade. But experts warn driving is far from back to its previous historical pattern.

According to new data from the Federal Highway Administration, total driving mileage climbed 1.7 percent in 2014, higher than the rate of population growth. Gas prices are likely a major factor. In the first half of 2014, driving rose only about 0.8 percent, about the rate of population growth, compared to the same period in 2013. But during the second half of the year, as gas prices dropped substantially, total miles driven shot up 2.5 percent.

Phineas Baxandall, a researcher with the U.S. Public Interest Research Group, says the increase needs to be put in perspective: This doesn’t look like a return to historical driving trends. Prior to about 2005, traffic rose at a fairly steady rate, with some fluctuation around recessions. But this latest increase doesn’t signal a return to that path of constant growth — the kind that has been continually used to justify highway projects.

“This past year saw big increases in employment and a precipitous dip in gasoline prices, yet the rate of increase in driving was still smaller than the normal increases for six decades before 2005,” Baxandall said in a statement. “The total volume of driving in 2014 still fell below 2007 levels, even despite the nation’s larger population.”

Of course, policy makers could also act to spare Americans from the burden of increasing traffic, congestion, and emissions. “The volume of driving could be even lower if public policies in coming years give Americans more choices about whether or not to drive,” Baxandall added. “We hope that this past year’s data does not distract public leaders from the profound changes underway in transportation.”


Americans Are Driving Less, But Road Expansion Is Accelerating

Notice how the new lane miles and miles driven depart in the upper right hand corner of this chart, via FHWA.

Starting around 2005, driving leveled off, but transportation agencies continued to expand roads. Click to enlarge. Chart: FHWA

Americans drive fewer miles today than in 2005, but since that time the nation has built 317,000 lane-miles of new roads — or about 40,000 miles per year. Maybe that helps explain why America’s infrastructure is falling apart.

The new data on road construction comes from the Federal Highway Administration and reached our attention via Tony Dutzik at the Frontier Group, which studies trends in driving. In 2005, Americans drove just above a combined 3 trillion miles. Almost a decade later, in 2013, the last year for which data was available, they were driving about 45 billion less annually — so total driving behavior had declined slightly. Meanwhile, road construction continued as if demand was never higher.

Between 2005 and 2013, states and the federal government poured about $27 billion a year into road expansion. According to FHWA data, road expansion was spread across highways and surface streets fairly uniformly.

That’s actually a faster pace than in previous decades, Dutzik points out. For the whole of the 1990s — when gas was cheap and sprawl development was booming — the country added, on average, about 17,000 lane-miles a year, less than half the current rate.

This is further evidence that America’s “infrastructure crisis” is due in large part to spending choices that favor new construction over maintenance.


The Feds Quietly Acknowledge the Driving Boom Is Over


After years of erroneously predicting rapid growth in driving, the FHWA finally made significant downward revisions to its traffic forecast last year. Graphic: U.S. PIRG/Frontier Group

The Federal Highway Administration has very quietly acknowledged that the driving boom is over.

After many years of aggressively and inaccurately claiming that Americans would likely begin a new era of rapid driving growth, the agency’s more recent forecast finally recognizes that the protracted post-World War II era has given way to a different paradigm.

The new vision of the future suggests that driving per capita will essentially remain flat in the future. The benchmark is important because excessively high estimates of future driving volume get used to justify wasteful spending on new and wider highways. In the face of scarce transportation funds, overestimates of future driving translate into too little attention paid to repairing the roads we already have and too little investment in other modes of travel.

The forecast is a big step forward from the FHWA’s past record of chronically aggressive driving forecasts. Most recently, in February 2014 the U.S. DOT released its 2013 “Conditions and Performance Report” to Congress, which estimated that total vehicle miles (VMT) will increase between 1.36 percent to 1.85 percent each year through 2030. This raised some eyebrows because total annual VMT hasn’t increased by even as much as 1 percent in any year since 2004.

Comparing the 20-year estimates of the “Conditions and Performance Report” issued at the beginning of 2014 to the new 20-year estimates shows the agency has cut its forecasted growth rate by between 24 percent to 44 percent.

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The Great Traffic Projection Swindle

This is the final piece in a three-part series about privately-financed roads. In the first two parts of this series, we looked at the Indiana Toll Road as an example of the growth in privately financed highways, and how financial firms can turn these assets into profits, even if the road itself is a big money loser. In this piece, we examine the shaky assumptions that toll road investments are based on, and how that is putting the public at risk.


A consultant predicted traffic on the Indiana Toll Road would rise 22 percent in seven years. Instead, traffic fell 11 percent in eight years. Photo: Jimmy Emerson/Flickr

For privately financed toll road deals, traffic projections are critical. These forecasts tell investors how much revenue a road will generate, and thus whether they should buy a stake in it, and what price to pay. While traffic projections have underpinned the rapid growth in privately financed highways, the forecasts have a dismal track record, consistently overstating the number of drivers who will pay to use a road.

Private toll roads have been sold to the public as a surefire something-for-nothing bargain — new infrastructure with no taxes — but it turns out that the risk for taxpayers is actually substantial. The firms performing traffic projections have strong incentives to inflate the numbers. And the new breed of private finance deals are structured so that when the forecasts turn out wrong, the public incurs major losses.

Given the large sums of money involved, even small errors in traffic projections can result in huge problems down the line — and, as Streetsblog has reported, traffic projections everywhere have tended to be wildly off-target. A whole financing scheme, meant to last for generations, can easily be sunk in just a few years by exaggerated traffic projections. The Indiana Toll Road, purchased in 2006 for $3.8 billion, is a great example. The firm that owned it, ITR Concession Co. LLC, declared bankruptcy in September.

Wilbur Smith Associates had predicted that traffic volumes on the Indiana Toll Road would increase at a rate of 22 percent over the first seven years. Instead, traffic volumes shrank 11 percent in the first eight. The result was financial disaster for the concession company, owned jointly by Australian firm Macquarie and Spanish firm Ferrovial. By the time they filed for Chapter 11, debt on the road had ballooned to $5.8 billion.

The company blamed the recession for putting a damper on truck traffic. The same story was offered on another bankrupt Macquarie-owned project, San Diego’s South Bay Expressway. But is that explanation sufficient?

UK-based consultant Robert Bain literally wrote the book on traffic projections, warning in 2009 against forecasters who blamed faulty predictions on the economy [PDF]. Commenting on the flurry of global toll highway bankruptcies that was just starting then, Bain said they had “less to do with the present economic climate, and more to do with a market readiness to be seduced by hopelessly optimistic traffic and revenue projections.”

Bain went on to list 21 ways in which forecasters systematically overestimate future traffic. Each one may tilt the forecast by a tiny amount, but cumulatively they result in significant errors. Some of the typical mistakes indicate that forecasters have not yet acknowledged the broader decline in driving and sprawl underway, while others “underestimate the reluctance of some to paying tolls.” Bain argued for a paradigm shift in the use of traffic projections, recognizing that many of them “resemble statements of advocacy rather than unbiased predictions.”

Phineas Baxandall, a senior researcher with the U.S. Public Interest Research Group who’s written extensively for Streetsblog on trends in driving, says the engineering firms that provide the figures know how things work. “Companies seeking investment for privatized toll roads shop for the forecasting they want,” he said. “[There’s] no incentive to tell bad news. And if the deal appears promising, then the forecasting company gets other opportunities to sell further analysis, legal advice, raising debt, selling equity, etc.”

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Not Just a Phase: Young Americans Won’t Start Motoring Like Their Parents

Image: U.S. Public Interest Research Group

Young adults in 2009 were driving less and walking, biking, and riding transit more than young adults in 2001, according to the National Household Travel Survey. Chart: U.S. Public Interest Research Group

A raft of recent research indicates that young adults just aren’t as into driving as their parents were. Young people today are walking, biking, and riding transit more while driving less than previous generations did at the same age. But the vast majority of state DOTs have been loathe to respond by changing their highway-centric ways. 

A new report by the U.S. Public Interest Research Group points out the folly of their inaction: If transportation officials are waiting for Americans born after 1983 to start motoring like their parents did, they are likely to be sorely disappointed.

Though some factors underlying the shift in driving habits are likely temporary — caused by the recession, for instance — just as many appear to be permanent, the authors found. That means American transportation agencies should get busy preparing for a far different future than their traffic models predict.

“The Millennial generation is not only less car-focused than older Americans by virtue of being young, but they also drive less than previous generations of young people,” write authors Tony Dutzik, Jeff Inglis, and Phineas Baxandall.

There’s a good deal of evidence that the recession cannot fully explain the trend away from driving among young people. Notably, driving declined even among millennials who stayed employed, and “between the recession years of 2001 and 2009, per-capita driving declined by 16 percent among 16 to 34 year-olds with jobs,” the authors write.

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