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Posts from the "Traffic" Category

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Transpo Agencies Are Terrible at Predicting Traffic Levels

This chart contrasts state DOTs' projected traffic volumes with those actually recorded by the Federal Highway Administration. Image: ##http://www.ssti.us/2013/12/new-travel-demand-projections-are-due-from-u-s-dot-will-they-be-accurate-this-time/?utm_source=SSTI+Community+of+Practice+Master+List&utm_campaign=cbd2d0b53a-December_6_2013_newsletter12_16_2013&utm_medium=email&utm_term=0_f54dd1d9a6-cbd2d0b53a-45447449## SSTI##

Combined traffic projections from state and regional transportation agencies (the colored lines) have been wildly off the mark (the black line shows real traffic levels) for more than a decade. Image: SSTI

Americans’ travel behavior is changing dramatically. It seems like not a week passes without a new report about the decline in driving. But are state and local transportation agencies — which are responsible for much of the nation’s highway and transportation planning — keeping up with the facts on the ground? A review of the evidence by the State Smart Transportation Initiative finds the answer is a definitive “No.”

Forecasts and assumptions about ever-increasing traffic are often used to justify agency decisions to expand roads. But these assumptions are increasingly divorced from reality. In fact, state and regional agencies aren’t just wrong some of the time. State DOTs and metropolitan planning organizations are getting it wrong every year, over and over again, by significant margins, according to SSTI’s analysis.

In their most recent reporting to the Federal Highway Administration, state and regional transportation agencies used data from 2008 to predict that traffic volumes would reach a combined 3.3 trillion miles nationally in 2012. Last year, a few months after that forecast was publicly released, real-world data already showed that the forecast wasn’t even close. Transportation agencies had collectively overestimated how many miles Americans would drive in 2012 by 11 percent. That is the equivalent of adding five “average-sized” states to the total, SSTI reports.

What’s worse, these wildly incorrect traffic assumptions are routinely used to justify costly road expansions.

SSTI reviewed every 20-year traffic forecast submitted by state and regional agencies to FHWA since 1999 (these predictions are in a document called the Conditions and Performance Report to Congress). It turns out that the 20-year projections overestimated future traffic volumes in every single year the reports could be compared against data on actual miles driven by Americans. The 1999 report, for example, overestimated actual driving in 2012 by a whopping 22 percent.

SSTI’s Eric Sundquist concluded that states and MPOs ”generally have not updated their models and assumptions to account for current conditions, as if they expect the year to be 1980 forever.”

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Study: All Across America, Car Commuting Is Dropping

Driving is declining and non-driving transportation is increasing in urbanized areas. Image: U.S. PIRG and the Frontier Group

Since 2000, car commuting has dropped across the board while other forms of travel have tended to increase in America’s 100 biggest urban areas. Image: U.S. PIRG and the Frontier Group

U.S. PIRG and the Frontier Group are on a mission to explore the downward trend in driving. In a series of reports, they point to evidence that it isn’t just a temporary blip, but a long-term shift in how Americans get around. Today, the two organizations released a new report, “Transportation in Transition: A Look at Changing Travel Patterns in America’s Biggest Cities,” which shows that these changes are happening in regions all over the country.

In 99 of the nation’s 100 largest regions — the cities and suburbs that are home to more than half the U.S. population — fewer people got to work in a private vehicle in 2010 than in 2000. In the vast majority of those areas, households are shedding cars while more people are getting on the bus and taking up biking. These 100 regions are the engines of the U.S. economy and where most of the nation’s population growth is happening.

Since state DOT data collection leaves much to be desired, PIRG and Frontier Group encountered some situations where they couldn’t do an apples-to-apples comparison. As a result, they examined vehicle miles traveled trends in only 74 of the 100 largest urbanized areas. In 54 of those, VMT had dropped. Across the country, mileage is down 7.6 percent per capita since 2004.

“Each city has a different story,” U.S. PIRG’s Phineas Baxandall said in an email. “Sometimes the stories are hard to see because the data is messy, but the overall picture suggests real changes in how people get around.”

The report kicks off with a lovely tale about one city’s fight to keep a highway from destroying downtown:

When Madison, Wisconsin, was given the opportunity to bring the interstate into the city in the 1960s, local officials decided to keep its downtown highway-free — they believed that a highway running through Madison’s narrow downtown isthmus would make the city less attractive. But without the Interstate, city officials needed to make sure that residents had access to other modes of transportation to travel down-town. So city planners sought to build a multimodal transportation network that promoted bicycling, public transit and walking.

And guess what? Those investments are still paying off. As attitudes about transportation and urban living shifted over the past decade and more people decided to explore life outside the automobile, Madisonians had lots of good options to choose from. On average, each city resident drove 18 percent fewer miles in 2011 than in 2006 — from 8,900 miles down to 7,300. Meanwhile, biking to work soared 88 percent in the last 11 years, and bus ridership is way up.

U.S. PIRG and the Frontier Group encourage other places to follow Madison’s lead. Madison started investing in multi-modalism in the 1960s and 70s, when driving was still ascendant. Today, as Americans embrace transit and active transportation in greater numbers, driving declines, and new roads become increasingly poor investments, those same strategies should seem like ordinary common sense.

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Georgia Removes Tolls, Invites 11,000 More Drivers to Clog GA 400 Each Day

Why raise desperately needed transportation funds for a broke region when you could let people drive for free? In Georgia, the state has made up its mind: The DOT will pay $4.5 million to tear down tolls on GA 400 — and forfeit the $21 million a year the tolls brought in.

It's going to cost $4.5 million to tear down these toll booths, not to mention another $21 million a year in forfeited toll revenue. Photo: Creative Loafing

It cost drivers just 50 cents each to drive 54 miles north and east from the city of Atlanta on GA 400. But last July — just before voters in the region rejected an effort to fund a multi-modal transportation package — Gov. Nathan Deal announced that the bond debt was paid off and tolls would be removed this fall.

According to David Emory, president of Atlanta’s Citizens for Progressive Transit, the state decided to announce the toll repeal in the run-up to the T-SPLOST ballot initiative in hopes that it would appeal to voters and encourage them to vote for the transportation tax. “It ended up being a losing strategy,” Emory said, “because we’re losing the toll and the tax didn’t pass.”

It’s extraordinarily difficult to implement tolling on a road that had been free. On roads that receive federal funds, federal law prohibits tolling except for new construction. And politicians never want to ask drivers to pay for what they’re used to getting for free. So Georgia is for all intents and purposes foreclosing the possibility of having GA 400 users pay for the maintenance and upkeep of the road they drive on.

The state could also use those toll revenues for other projects that could take traffic off GA 400 and other roads, and reduce the pressure to build new highways in the future. The tolls have paid for express bus service along GA 400 and for a pedestrian bridge, among other projects, but there’s so much more that money could do.

MARTA’s red line runs right down the middle of GA 400 in places — and although the charge to drive on GA 400 is disappearing, “the fare on the MARTA line is definitely not going away,” Emory said.

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Heart Disease, Traffic Jams and ADHD Share One Simple Solution: Drive Less

This is an excerpt from “Bikenomics: How Bicycling Can Save the Economy,” by Elly Blue (Microcosm Publishing, December 1, 2013, bikenomics.com). See our interview with Elly from spring 2013. 

Car exhaust is no laughing matter. Nearly half of residents in major urban areas in North America live close enough to highways and other large roads to experience serious problems as a result. Exposure to car emissions worsens and may cause asthma and other lung conditions, including lung cancer. There is evidence to suggest that it leads to hardening of the arteries and thence to heart disease. One study has found an increased risk of heart attacks while in traffic, either while driving or using public transportation. Breathing car exhaust may increase the risk of developing diabetes; it is certain, however, that people who have diabetes suffer disproportionately from the effects of air pollution.

Traffic flows and air quality improved with the odd-even license plate restriction in Beijing during the Olympics. Photo: Traffic Technology Today

The worst effects of breathing polluted air are experienced where it is densest: in traffic. Spending time on and near highways, freeways, and other busy roads is terrible for your health. How near is a question that is still being studied, but researchers believe that the effects are worst within either a fifth or a third of a mile. People in cars or buses are exposed to considerably more air pollution, perhaps because of, rather than despite, being in a closed space. People walking and bicycling on or next to roads breathe more air, but inhale somewhat less pollution; and cyclists have been found to have even less risk if they are on paths that are separated from the road.

The burdens that come with air pollution are, as with so much else, not evenly distributed. Poverty and ethnicity are both major factors that determine the amount of car exhaust we breathe. Housing near a source of pollution, such as a freeway, busy road, or industrial site is generally where people with low incomes are able to live.

Children are particularly at risk, beginning before birth. Air pollution affects prenatal development, and a recent study suggests that exposure to air pollution such as diesel particulates, mercury, and lead may put a child at risk for autism. A separate study found double the rate of autism among children who live within 1,000 feet of a freeway in several major cities. Air pollution has also been linked, tentatively, to hyperactivity in kids and childhood cancers. And kids who have high daily exposure to car exhaust score lower on intelligence tests and have more depression, anxiety, and attention problems. This isn’t just a matter of where children live – one in three public schools in the U.S. are within a quarter mile of a highway, well within the danger zone.

Traffic jams and air pollution are often talked about at once, as though one inevitably causes the other, and that by fixing one you can also solve the other.

It doesn’t quite work that way.

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SSTI to Transport Officials: Start Planning for a Future With Less Driving

For a long time in the United States, driving activity moved in step with the economy. Since economic growth was fairly steady, consistent growth in driving was built into all the traffic modeling the engineers used to plan and build streets and transportation infrastructure.

Annual, per-capita vehicle miles traveled by Americans have been declining for eight years. Image: State Smart Transportation Campaign

But now per capita driving has declined eight straight years in America. Total vehicle miles traveled (VMT) hasn’t really budged in five years, and remains below its peak. A number of things have fundamentally changed since the time when you could chart driving behavior into the future using an upward line, according to a new paper by the State Smart Transportation Initiative, a think-tank based out of the University of Wisconsin which counts 19 state DOTs among its partners.

SSTI rejects the idea that driving declines reflect the recent recession, noting that the current slump began in 2004, well before the recession started. Driving activity actually began to decouple from economic growth in 2000, SSTI says, and today they do not appear to be strongly related.

The reasons for the current decline, SSTI reports, are broad cultural and economic trends that are likely to be “permanent,” or “remain in effect for a generation or more.”

In the decades prior, driving increases were triggered by factors like rising household income and auto ownership rates, increasing participation in the workforce by women, and the swelling ranks of Baby Boomers in their most active driving years. Today, however, those trends have abated or are moving in the opposite direction.

Baby Boomers are beginning to retire, and entering a stage in their lives when they will drive less and less. The American market for car owners is mostly saturated. Meanwhile, the growth in women’s workforce participation leveled off more than 10 years ago.

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After the Addition of Bike Lanes and Plazas, Manhattan Traffic Moves Faster

Car traffic into Manhattan has basically stayed flat since the recession, while transit ridership has started to rebound. Image: DOT

After several blocks in the heart of Times Square were pedestrianized and protected bike lanes were added to five avenues in the middle of Manhattan, motor vehicle traffic is actually moving more smoothly than before, according to the latest release of NYC DOT’s annual Sustainable Streets Index [PDF].

The report, which gathers data from the MTA, the Taxi and Limousine Commission, and DOT’s own counts, also shows that the volume of traffic entering Manhattan has basically stayed flat since 2009. At the same time, transit ridership has started to rebound from the recession and service cuts.

Even with population and employment levels increasing after the recession, car traffic into the Manhattan CBD declined 1.7 percent in 2011. Since 2003, traffic volumes are down 6.5 percent, while transit trips to the area have increased 11.3 percent.

The drop in Manhattan-bound traffic has come primarily from the Hudson River tunnels, which have seen a 3 percent drop since 2008, while volumes on the free East River bridges remained flat and traffic over the free Harlem River bridges inched up 1 percent. (It’s no surprise why: Port Authority tolls encourage people to take transit or carpool, while the city’s free bridges offer no such incentive.)

In Manhattan below 60th Street, predictions that reallocating space to walking, biking, and transit would only worsen traffic have not come to pass. In fact, average traffic speeds have picked up. GPS data from yellow cabs below 60th Street show that average speeds are up 6.7 percent since 2008. The average speed of a taxi trip, which was 8.9 mph in 2011, inched up to 9.3 mph last year. (Note that these average speeds don’t mean, as Matt Flegenheimer put it in the Times this morning, that “drivers in much of Manhattan can rarely flout the law, even if they try.” In addition to aggressive and dangerous behavior like failing to yield to pedestrians, speeding in Manhattan is still very common even if average speeds are well below the limit.)

Manhattan’s business districts aren’t the only places where transit is on the rise as driving volumes fall. According to metrics incorporating car crossings between boroughs other than Manhattan, citywide traffic volumes declined 1.8 percent in 2011 from the previous year, while transit ridership increased 0.4 percent, despite service cuts and fare hikes implemented the year before. The most recent numbers are in line with a long-term trend: Since 2003, NYC transit ridership is up 9.5 percent, while driving counts have fallen 3.9 percent.

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More Evidence That Unemployment Doesn’t Explain the Decline in Driving

Only one state shows up on the Top Ten lists for both VMT reduction and unemployment increase: Florida. But Nevada, whose jobless rate has tripled, actually increased driving. Source: U.S. PIRG

For those who say driving rates will pick right back up again when the economy’s really humming, here’s something to chew on: In a report released this morning, “Moving Off the Road,” U.S. PIRG presents further evidence that unemployment rates and driving rates have changed independently of each other.

Transportation reformers have made the case that there are multiple reasons behind the dip in driving rates, and that many of these factors will continue to have an impact long after this economic slump is over. If the change is in fact a lasting one, it signals that conventional forecasts of escalating traffic are wrong, strengthening the case for overhauling car-centric transportation policies in favor of transit, biking, walking, and more efficient land use.

Today’s report from U.S. PIRG builds on their previous, groundbreaking research showing that young people are leading the reduction in driving rates and that the Driving Boom has decisively ended. These findings have become common knowledge, frequently referenced by top federal officials, members of Congress, and even international credit rating agencies.

The Drop in VMT Isn’t About Unemployment

The PIRG report compares changes in driving and joblessness in all 50 states from 2005 to 2011. The authors call it “a useful natural experiment to examine different factors behind America’s reduction in driving,” and it provides ample evidence that unemployment doesn’t explain the drop in VMT. If the Americans were driving less because jobs are scarcer, for instance, it would stand to reason that the states hardest hit by unemployment would be those with the biggest drops in VMT. But that’s simply not true.

For example, the top state for unemployment growth was Nevada, whose jobless rate tripled between 2005 and 2011. And Nevada is one of just four states that’s actually driving more now than during the peak years of 2004-2005. (Two of those four states are in the Gulf South — Alabama and Louisiana — where the devastating Hurricane Katrina obviously affected travel during the driving peak year of 2005.)

And the number one state for VMT drop? Alaska, which has reduced its mileage by a whopping 16.23 percent since 2005. So Alaska must be suffering with staggering unemployment, right? Not so. Every state in the union experienced some growth in unemployment, but in Alaska it was just a 10 percent increase — from 6.9 to 7.6 percent.

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Car Ownership May Be Down in the U.S., But It’s Soaring Globally

The number of cars per person more than doubled in China in just four years. This BMW ad is designed for the booming Chinese market. Photo: Ads of China

Two weeks ago, transportation researcher Michael Sivak brought us the news that there are fewer cars per person in the U.S. now than there were a few years ago – and that the number isn’t expected to rise again.

But globally, the trend is in the opposite direction, and it’s alarming. The world is producing more cars than ever. A new report from the Worldwatch Institute shows that automobile production hit a new high in 2012 — and 2013 is expected to surpass that record. “According to London-based IHS Automotive, passenger-car production rose from 62.6 million in 2011 to 66.7 million in 2012, and it may reach 68.3 million in 2013,” write Worldwatch’s Michael Renner and Maaz Gardeziin. “When cars are combined with light trucks, total light vehicle production rose from 76.9 million in 2011 to 81.5 million in 2012 and is projected to total 83.3 million in 2013.”

The troubling new reality is that while the United States and other developed countries are beginning to lay off the gas, other countries are accelerating wildly. Though the U.S. still has by far the largest fleet of passenger cars, auto sales in China overtook the U.S. in 2011. In 2010, the number of cars in the world hit one billion.

Taken together, Brazil, Russia, India and China (the "BRICs") buy more cars that the United States. Image: The Economist

The number of cars per person in the U.S. has been declining since 2006. But in other countries, the trend is ever upward. According to World Bank data, there were 18 passenger cars per 1,000 Chinese in 2006 and 44 cars per 1,000 in 2010. The Arab world and Eastern Europe have seen tremendous growth in private car ownership over the same period – from 87 to 123 cars per thousand people in Jordan, 18 to 36 in Syria, 230 to 345 in Bulgaria, 351 to 451 in Poland. In the meantime, U.S. rates declined from 453 to 423 per thousand. France, New Zealand, and the United Kingdom also saw declines.

In 2011, the OECD’s International Transport Forum forecast that the number of cars worldwide would reach 2.5 billion by 2050, with the growth expected to be almost entirely in the developing world. At an ITF meeting, a Chinese professor dismissed the idea of bicycles as an alternative means of transportation, despite the fact that China is famous for its bicycle rush hour. The professor said, apparently without irony, that bicycle use in Beijing is declining “due to poor air quality and the danger from car traffic.”

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How Better Traffic Models Can Lead to More Mixed-Use Development

Here’s another obscure but significant obstacle to building walkable places in America: the Institute of Transportation Engineers’ shoddy traffic generation models for mixed-use development.

The model used by traffic engineers around the country to measure “trip generation” at new developments consistently overestimates the amount of motor vehicle traffic produced by mixed-use projects, according to the Environmental Protection Agency. This often increases the cost of building mixed-use projects, because the developers are asked to take steps to compensate for the added traffic. To address this problem, the EPA worked with transportation researchers around the United States to develop a better traffic prediction model.

Current traffic modeling overestimates the traffic caused by mixed-use development by about 35 percent, on average. Image: Kyle Gradinger on Twitter

Reid Ewing, a transportation engineering professor at the University of Utah, helped develop the new model to forecast the traffic generation of walkable development. I caught up with him at the Congress for New Urbanism conference last week in Salt Lake City.

Angie Schmitt: Can you explain the new method?

Reid Ewing: There’s a current methodology, which is the Institute of Transportation Engineers’, and it overestimates the number of external vehicle trips generated by a development if the development has mixed uses. If it’s got residential, retail, and office, those uses interact and a lot of trips stay within the development. And if it’s a development downtown, a lot of those trips that leave the development are walk and transit trips. ITE doesn’t account for that, it doesn’t account for the full number of trips that will stay within a development or the use of alternative modes for those that leave the development. So we developed a methodology.

AS: How many trips are reduced by mixed-use development?

RE: It varies from almost zero to over 50 percent. In a master planned community, it’s huge — a lot of the trips are going to stay within the community. If you have a stand-alone, freeway-oriented community that happens to have mixed-used, a much smaller percentage will stay within the community. But on average, about 35 percent. So the ITE method seems to overestimate by, on average, about 35 percent.

AS: So, how does the ITE method cause problems?

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Seven Ways Technology Is Rendering the Automobile Obsolete

As we try to understand why young people are so much less jazzed about driving than previous generations, one possible explanation always comes up: Kids today just love their smart phones.

That is part of it. But the full picture is far more nuanced.

The internet, and the ability to carry it wherever you go, has changed society in so many profound ways it’s no surprise that transportation is among them. A new study by U.S. PIRG and the Frontier Group, “A New Direction,” illustrates the myriad ways mobile technology has transformed young people’s relationship with transportation.

Yesterday, we covered the report’s critique of government travel forecasting and its analysis of why young people’s driving rates will probably remain lower than those of previous generations. Technology is one of the biggest reasons. Here’s why:

Go ahead, check your stocks online – but not if you’re behind the wheel, please. Photo: PC Mag

Constant connectivity. As you’ve undoubtedly noticed at the dinner table or on city sidewalks, people have trouble putting down their phones. It’s not just compulsive Facebook status checking that keeps people glued to their devices. People perform an increasingly broad assortment of tasks on phones: make travel reservations, go through work email, catch up on the news, diagnose children’s ailments — the list is nearly infinite. While car companies are trying heartily to incorporate digital connectivity and social media into their cars, they still need to battle the fact that such technology is dangerously distracting for drivers. Given the option, many young people would rather take transit, where they can use their phones harmlessly, making far better use of their commuting time.

Alternative social spaces. Older adults may think it’s weird when teens would rather text each other than see each other, but hey, the world is a weird place. “A survey by computer networking equipment maker Cisco in 2012 found that two-thirds of college students and young professionals spend at least as much time with friends online as they do in person,” write report authors Phineas Baxandall and Tony Dutzik.

Online shopping. More and more people are making purchases online rather than in stores. Young people are leading the way on that, too. And it can be greener than going to the store yourself.

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