US DOT keeps overestimating future Vehicles Miles Traveled

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afigg

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The Washington Post Wonkblog section has a short article that I found of interest on the question of whether the US highway departments are getting too much money for building new roads and highways in expectation of future traffic volume that may never happen. There are obviously multiple reasons for the near plateau in total VMT since circa 2005, but I suspect that most policy planners and politicians are oblivious that total VMT has been flat since then. The numbers have bearing on the issue of whether passenger rail and transit systems should get a bigger piece of the transportation funding pie, although I expect these stats will have little effect on the roads vs passenger rail funding in the near term in most states and in Congress.

The U.S. government keeps predicting we’ll drive more than we actually do Excerpt:

Sundquist and Tony Dutzik of the Frontier Group sifted through a half-dozen old U.S. Department of Transportation reports to Congress and found a trend: Since 1999, the agency has consistently predicted that U.S. vehicle-miles traveled would rise dramatically (based on state and local forecasts). In reality, the opposite happened. The growth in vehicle travel slowed and then appeared to "peak" around 2007.

There's still lots of debate about why Americans are driving less since 2007. Some of it may be due to temporary factors like the recession (unemployed people tend to drive less). Some may be due to long-term trends like the aging of America (retirees drive less). Or higher gasoline prices (a deterrent against road trips). Young people are also driving less, and there are a slew of theories as to why: It's getting more expensive to buy a car, the barriers to getting a license are increasing, Facebook makes it easier to hang out with friends without driving...

Few people were predicting that shift (though here's one exception) — so it's not surprising that official forecasts missed it. But what's notable is that the forecasts still haven't caught up. Even as the number of vehicle-miles traveled drooped after 2007, the agency kept predicting significant increases. (We'll see how these forecasts get updated in the agency's 2012 report, which is due out soon).
Here is the chart of the forecasts for total Vehicle Miles Traveled (in trillions!) going back to 1999 with the black line as the actual number measured. The gap between the actual VMT in 2012 and the 1999-2004 forecasts for 2012 is really big.

VMT-C-P-chart-big.png
 
There was a similar phenomenon with respect to Japanese birth rates for about 40 years, with all forecasts predicting a substantial bump in birth rates over what was happening. Aside from one or two small bumps, the rate trended flat-to-down, but the official forecasts never really caught up.

Of note, this problem is also showing up in land use planning for WMATA, among others. Partly because of federal policies trickling down onto local policy, a number of suburban areas are projecting sprawl-y growth patterns that are very clearly not panning out. However, because a number of agencies are largely tied to bad forecasts, you're getting awful long-term plans that aren't accommodating what's happening. I'll grant some skepticism about trends continuing indefinitely, but you'd think there would be some acknowledgment of this at one level or another in the form of less aggressive forecasts.
 
Another thought: The number of occupants per vehicle also declined during the past WW2 years. During my course in highways engineering (in the mid 1960's) the professor pointed out, as a fallacy in making straight line projections, that if the trend contiued, that by 1990 (or some other day, I can't remember) one-fourth of the cars on the road would be empty.
 
Another thought: The number of occupants per vehicle also declined during the past WW2 years. During my course in highways engineering (in the mid 1960's) the professor pointed out, as a fallacy in making straight line projections, that if the trend contiued, that by 1990 (or some other day, I can't remember) one-fourth of the cars on the road would be empty.
Don't know how I missed this one? Here in Austin (Gridlock Capitol of America!) Estimates are that over Half the Vehicles on the Road are Empty due to Drivers that are Engrossed in Hi-Tech Operation/Useage! :help: :rolleyes:
 
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http://usa.streetsblog.org/2014/03/03/lets-do-the-time-warp-again-u-s-dot-fails-to-get-travel-forecasting-right/

For all that Streetsblog has an evident bias on some things, they've been pretty spot-on with the constant driving over-projection in a bunch of forecasts. Granted, USDOT's hands seem to be at least somewhat tied by state reports, but I'm seriously wondering why they haven't either (A) fired whomever is doing the analysis (assuming the issue is on their end), (B) started refusing to use some state projections that apparently have absurdly flawed projections of years that have already happened, or © openly called some of the projections unrealistic and pointed out that they're being forced into a GIGO situation. Even assuming the DOT doesn't have the ability to produce their own data, I'd think that either (B) or © would be doable considering how wrong the projections have been/continue to be.
 
The issue of slower growth or decline in car and truck traffic since the early aughts is popping up in local news articles on plans for ever wider roads and bridges. Philadelphia Inquirer: Drop in traffic on area highways forces review of plans. Article discusses the plan hatched some years back to use PA Turnpike toll revenue as a piggybank which has not worked out very well, widening of the NJ Turnpkike, a bridge replacement project,

The leveling off in VMT growth over the past 10 years is starting to sink in. If you are a transportation planner and you have a 4 lane bridge that needs to be replaced, and let's say that is a busy bridge with only occasional traffic jams at rush hour, what do you replace it with? Another 4 lane bridge with wider shoulders, a 6 lane bridge, or go all out with an expensive 8 or 10 lane bridge megaproject? What happens if the really expensive 8 or 10 lane toll bridge is built, but traffic and toll revenue fall far short of the projections 10 and 15 years out? If you overshoot on the bridge capacity and toll revenues fall far short of the amounts needed to pay off the bonds, who ends up holding the bag? The bond holders or the local taxpayers?

Some excerpts from the article:

Before beginning a $2.5 billion project to widen the New Jersey Turnpike, turnpike officials said the construction was necessary to reduce existing congestion and to cope with future traffic.

"Turnpike traffic is on the rise," the state Turnpike Authority said in its justification for the project. "By 2032 northbound traffic volume is expected to increase by nearly 68 percent [above 2005 levels]; southbound traffic is forecasted to increase by 92 percent."

Now, one-third of the way through that 27-year forecast, turnpike traffic is actually about 10 percent lower than it was in 2005.

Similar traffic declines have occurred around the region, challenging long-established assumptions about the need for bigger highways and bridges.

"If these trends continue, it would definitely change the way we need to plan for our transportation future," said Chris Puchalsky, associate director of systems planning at the Delaware Valley Regional Planning Commission. "But I think the jury is still out on that . . . we need two or three more years of data."
Traditional expectations of economic growth - which typically fuel traffic growth - were undone by the recession of 2001, the Great Recession of 2007-2009, and anemic job growth for the entire decade, Hughes said.

Add to that the unprecedented behavior of young adults, driven by technology, lifestyle choices, and economic prospects.

"The millennials are really changing the world dramatically," Hughes said. "We have a younger generation that is driving less and doesn't want to live in Valley Forge. They want to live in Center City Philadelphia."

"We had a 50-year period of unrestricted suburbanization, and now there's a dramatic shift."

Cars and driving are less important to young adults, who find that trains and buses allow them to work and socialize on mobile electronic devices, he said.

That may mean fewer cars on future roads.

"Nobody was really anticipating this," Hughes said. "The models have to be recalibrated."
 
I'm wondering...how much of this behavioral shift might be similar to what happened in the 50s and 60s, where deteriorating transit services soured a generation on taking transit? I've seen a lot of charts that have shown that highway congestion basically went to hell in the 90s in a lot of cities. A decade of hearing mom and dad complain about their commute (or being late to games, etc.) can go a long way towards souring someone on driving.

Edit: This is just another factor that hadn't hit me until now, but I can't help but think back to many, many years of hearing my parents talk about the commute into Newport News (and notice it getting worse as time went on). I was spared the worst of it (I had a "reverse commute" to school when I moved in with my grandmother), but a couple of years of shuttling back and forth didn't do wonders for my outlook on it all the same.
 
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Can DOTs Help Themselves?
There’s an old fable about a scorpion and a frog: the frog generously offers to carry a scorpion across a river…but halfway across, the scorpion stings the frog, drowning them both. With its dying breath, the frog asks why the scorpion did something so stupid, and the scorpion replies: “I can’t help myself. Stinging is what scorpions do!”

I thought of this fable when a saw this new chart from the State Smart Transportation Initiative, comparing the US Department of Transportation newest vehicle travel forecasts with previous versions. Like the scorpions in the fable, it seems the nation’s traffic forecasters just can’t help themselves: forecasting rapid traffic growth is just what DOTs do....

The dotted green line, however, seems to be USDOT’s attempt to develop a more nuanced forecast, based on actual traffic growth over the 15 years prior to 2010. But even that forecast is already badly wrong!! It projected 1.36 percent annual traffic growth, starting in 2010. The actual trend: -0.7 percent, +0.3 percent, and +0.6 percent. That adds up to almost no net growth since 2010, instead of the extra 120 billion miles of vehicle travel the USDOT had been projecting.

The scorpion could blame its DNA. But the stubbornness of transportation professionals requires a different explanation. One place to start is to look at the incentives that DOT forecasters (and their bosses) face. Many state DOTs exist largely to plan and execute major highway expansion projects. So if the forecasters aren’t projecting rapid growth, the new highways may not seem all that necessary…and the gravy train of new projects could dry up.

So perhaps the reason that state DOTs don’t make accurate forecasts is that they simply can’t afford to make accurate forecasts....
 
Yes, there seems to be an inherent conflict of interest and a natural unwillingness to say "Hey, we're not going to need as many resources next year - please take some of our money and fire half of us".
 
Yes, there seems to be an inherent conflict of interest and a natural unwillingness to say "Hey, we're not going to need as many resources next year - please take some of our money and fire half of us".
True, though at some point it would behoove some of the elected officials being faced with wasteful projects and horribly misguided projections to start either re-directing money or, frankly, sending DOT secretaries in with a mission to clean up the mess.

I can sorta give them a pass for the first few years of this, but a decade should be long enough to at least start slowing the growth projections.

Edit: Even putting in a watchdog to deal with atrociously bad projections (both here and elsewhere) might be helpful.
 
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Here in Washington state, inaccurate VMT projections have been talked about since at least 2008. But we're potentially talking about reversing the conventional wisdom that the future holds more cars and more driving: something that's been taken for granted for a century. It may take a long time for that reversal to happen, unless "we the people" make it a priority.
 
I do not expect Congress to do anything about it. Afterall they have fought reduction in production of individual items that the armed forces say they don't need anymore too, in order to preserve the flow of the gravy. As long as road building contracts are considered to be gravy to be brought home, Congress will resist. Cynical? Moi? ;)
 
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I think I know what will spark a change...

Given how these projections likely get mentioned in some highway bond issuances and/or in prospectus material for toll road investments, at what point does including chronically and excessively wrong projections become securities fraud?
 
I do not expect Congress to do anything about it. Afterall they have fought reduction in production of individual items that the armed forces say they don't need anymore too, in order to preserve the flow of the gravy. As long as road building contracts are considered to be gravy to be brought home, Congress will resist. Cynical? Moi? ;)
No, I would call it realistic. Especially at the state level where the state political leadership and political appointees are of the generation(s) where economic progress has been measured by the new highways, road, and suburban/exurban sprawl that are built. The cost of maintaining all those roads and sprawling exurbs is the next generation's problem. Meanwhile, take those campaign donations from the highway and road lobbyists.
 
I do not expect Congress to do anything about it. Afterall they have fought reduction in production of individual items that the armed forces say they don't need anymore too, in order to preserve the flow of the gravy. As long as road building contracts are considered to be gravy to be brought home, Congress will resist. Cynical? Moi? ;)
No, I would call it realistic. Especially at the state level where the state political leadership and political appointees are of the generation(s) where economic progress has been measured by the new highways, road, and suburban/exurban sprawl that are built. The cost of maintaining all those roads and sprawling exurbs is the next generation's problem. Meanwhile, take those campaign donations from the highway and road lobbyists.
At the rate things are going, I think there's a very good chance that the "next" generation is simply going to choose not to keep up some of those roads (or at the very least, kick the cost onto the residents of those neighborhoods).
 
Driving Declines Spell Big Trouble for Turnpikes

What the New Jersey Turnpike Authority did in 2005 was no different than what almost every other state and regional transportation agency was doing at the time. It predicted that traffic volumes would rise at a healthy clip every year for about 30 years into the future. Then it estimated its revenues based on those figures and issued bonds for a $2.5 billion road widening project.


Today we know that traffic hasn’t risen at all since 2005. New Jersey’s projections weren’t just a little wrong — they were wildly inaccurate. The bonds were predicated on a 68 percent increase in traffic by 2023. It’s not going to happen: The Philadelphia Inquirer reports that turnpike traffic has actually dropped 10 percent since 2005....

The Pennsylvania Turnpike Commission made a similar gamble in 2007, when it predicted traffic would rise 3 to 5 percent annually and started issuing up to $900 million in bonds annually for road and transit projects around the state based on those projections. Rather than rising, the Inquirer reports, traffic has been flat. Pennsylvania hoped to repay the bonds with the increased toll revenues and by adding tolls to I-80.

But the additional traffic never materialized, and the Federal Highway Administration rejected the proposed toll on I-80. Now the turnpike is paying much less every year for state transportation projects, but it is still saddled with a rising debt load — $8 billion, according to the Inquirer.

Here’s the kicker. Nikolaus Grieshaber, the turnpike’s chief financial officer, told the Inquirer that Pennsylvania is revising its projections downward. It will now predict a traffic increase of 1.5 percent annually.

Nationally, vehicle miles traveled increased 0.6 percent last year, so Pennsylvania is still predicting its traffic will increase two and half times faster than the nation as a whole in 2013.
 
State DOTs Let Roads Fall Apart While Splurging on Highway Expansion

Even though 33 percent of its roads are in “poor” condition, West Virginia spends about 73 percent of its road budget building new roads and adding lanes. Mississippi spends 97 percent of its road money on expansion. Texas, 82 percent.


Smart Growth America reports that the 50 states and the District of Columbia, combined, devote 55 percent of their road spending — $20.4 billion a year — to expansions, according to data states provide to the Federal Highway Administration. Between 2009 and 2011, that investment added 8,822 lane miles to the nation’s highway system — meaning that more than half of states’ road dollars were dedicated to less than 1 percent of their roads.

Meanwhile, states spent $16.5 billion annually, or 45 percent of their total road budgets, maintaining and repairing the other 99 percent of the nation’s roads.

In total, 21 percent of America’s roads are in “poor” condition, based on an international index that measures ride quality and surface smoothness. And the condition of the nation’s roads is getting worse. The last time Smart Growth America checked in, in 2008, 41 percent were in “good” condition. By 2011, that figure was down to 37 percent.
 
Overestimating traffic is hitting home here in Seattle.
One (Unanswered) Question for WSDOT on the Tunnel


...Traffic on the viaduct [the waterfront freeway that is to be torn down and replaced by a tunnel] has actually declined precipitously since deep-bore tunnel construction began, declining from more than 110,000 trips per day in 2009 to 62,000 in 2012. And that reduction can't be attributed to people simply driving on alternate routes; ...traffic through downtown Seattle declined overall during the same period, dropping 8 percent, "meaning that between 2010 and 2012, about 1 trip out of 12 vanished."

During the debate over whether to build the tunnel, proponents of the surface/transit option argued that when you eliminate highway lanes that primarily serve cars, people make different choices, opting to take transit, choose alternate routes, combine trips, drive at different times, or avoid unnecessary trips altogether. Now, it looks like that's exactly what they're doing.

So, during a tunnel press call today, I asked what seemed like an obvious question: What was tunnel deputy project manager Matt Preedy his reaction to plummeting traffic volumes on the viaduct? Given that people are using the viaduct less and less, is the tunnel—which, again, was justified in part by the argument that the state must preserve traffic capacity on a critical highway—even necessary anymore?

With the tunnel-boring machine stuck until at least September, and delays and cost overruns looking increasingly likely, this seems like an opportune time for WSDOT to consider that question.

Preedy, however, declined to answer. "I really don't have any comments on that. I wasn't a part of the development team for the tunnel concept," he said.
 
Vehicle Miles Driven: Another Population-Adjusted Low

The Department of Transportation's Federal Highway Commission has released the latest report on Traffic Volume Trends, data through December.
Travel on all roads and streets changed by -1.3% (-2.9 billion vehicle miles) for January 2014 as compared with January 2013 (see report). However, if we factor in population growth, the civilian population-adjusted data (age 16-and-over) is at a new post-Financial Crisis low and total population-adjusted data are only fractionally above its low set in June of last year.
 
Looks like Virginia is in for a significant change of course at VDOT in transportation funding priorities under the McAuliffe administration. The deputy secretary of Transportation showed the actual VMT versus projected VMT chart to the Commonwealth Transportation Board as part of arguing for a re-appraisal of former Gov. McDonnell more controversial road projects. How about take 1/2 of the state funds that were to the go to the questionable Rt. 460 Connector and use them for freight & passenger rail upgrades between Richmond and Norfolk and Newport News?

Bacons's Rebellion: Virginia’s Behind-the-Scenes Transportation Planning Revolution

The McAuliffe administration is generating big headlines by re-thinking mega-projects like the Charlottesville Bypass and the U.S. 460 Connector favored by the previous administration. Those projects came to the fore because federal regulatory authorities made it clear they had major problems with them, leaving Transportation Secretary Aubrey Layne scrambling to keep ahead of the situation. But if you want clues to what long-term transportation strategy will look like under Governor Terry McAuliffe, the man to watch yesterday was Nicholas Donohue, the deputy secretary of transportation.

Donohue briefed the Commonwealth Transportation Board (CTB) about VTrans, Virginia’s long-term transportation planning process, explaining how the McAuliffe team would take a different approach to forecasting travel demand and how the process for allocating road dollars would be subjected to a more rigorous cost-benefit analysis.
 
Dueling Forecasts: Does the Energy Dept. Know Something U.S. DOT Doesn’t?

DOT%20EIA%20forecast%20comparison%202_0.jpg



The U.S. Energy Information Administration (EIA) — the data and analytical wing of the Energy Department — is out today with a fascinating analysis of changing driving trends and their implications for America’s energy future. The analysis, part of the EIA’s annual package of forecasts called the “Annual Energy Outlook,” reviews recent changes in demographic, economic, technological and other factors affecting the number of miles Americans drive.

It also serves as a telling contrast to the U.S. Department of Transportation’s own recent forecast of vehicle travel, presented in the biennial “Conditions and Performance” report.

We’ve criticized the U.S. DOT before for regularly overshooting the mark when it comes to forecasting vehicle travel, exaggerating the need for spending on highway expansion and maintenance. The EIA report, on the other hand, takes a more nuanced and thoughtful approach to forecasting than the DOT’s reliance on untrustworthy state data and straight-line projections. It also gives us some key indications of what slower VMT growth might mean for our energy future....

The EIA and DOT have very different thoughts about how the future will play out when it comes to trends in driving. The DOT forecasts an immediate resumption of rates of vehicle travel growth that haven’t been seen for a decade, while the EIA assumes that, while driving might pick up again soon, it also might not, and that, to the extent driving does increase in the future, it is likely to grow way more slowly than it did during the post-war Driving Boom. This is the case we made in our 2013 report, A New Direction.

Incredibly, even the EIA’s “high VMT” case forecasts a level of driving that is below the DOT’s “low” forecast.
 
Vehicle Miles Driven: Another Population-Adjusted Low


The Department of Transportation's Federal Highway Commission has released the latest report on Traffic Volume Trends, data through March.

Travel on all roads and streets changed by 0.2% (0.5 billion vehicle miles) for March 2014 as compared with March 2013 (see report). However, if we factor in population growth, the civilian population-adjusted data (age 16-and-over) is at a another new post-Financial Crisis low, as is the total population-adjusted variant.
 
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