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InTransition Magazine : Transportation Planning, Practice & Progress

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Research Exchange

About Research Exchange

  • Research Exchange gathers brief summaries of ongoing or recently completed research about critical topics in transportation. We invite readers to suggest studies that merit inclusion.

Study: Red Light Cameras Helping Stop Texas Crashes

red light camera

A study by the Texas Transportation Institute (TTI) concludes that red light cameras are an effective means of minimizing crash-related deaths and injuries, having reduced crashes on red at intersections where they were installed statewide by a quarter.

The study, conducted by TTI’s Center for Transportation Safety, examined more than 11,000 crash records at the 275 Texas intersections where cameras were in place. According to the study, red light violations are responsible for more than 100,000 crashes and 1,000 fatalities annually in the U.S., and right-angle crashes account for 46 percent of all intersection-related collisions.

  • The analysis compared crash frequencies in each of the three years before and after the installation of each red light safety camera to measure the degree of change in crash data. Key findings of the study include:
    There was an overall reduction of 633 crashes at sites where cameras were installed, representing an
    11 percent decline in total crashes statewide.
  • Red light-related crashes dropped by 25 percent.
  • Right angle or T-bone crashes (the most severe type) dropped by 32 percent.
  • Reductions in crashes occurred across the board on all types of roadways, including business/primary roads, farm-to-market roads, interstate access roads, state highways, and U.S. highways.
  • There was a 23 percent reduction in crash frequency from one year before to one year after cameras were put into use.

“These findings show clearly that red light cameras offer significant safety benefits,” said Troy Walden, the author of the TTI study. “Most important, they help prevent the most severe and deadly type of intersection crashes.”

The full report, “Evaluation of Photographic Traffic Signal Enforcement Systems in Texas,” is available for free download

— Researchers: Troy D. Walden, Texas Transportation Institute.

Dog-Toting Motorists Show Risky Behavior

Dogs are, among other things, frequent travel companions for their owners. A July survey conducted by AAA and Kurgo, a manufacturer of pet travel products, found that motorists participated in a number of potentially dangerous activities while driving with man’s best friend.

For example, more than 50 percent of the respondents have taken a hand off the steering wheel to pet their dogs, a potentially distracting and dangerous activity. In addition, 23 percent respondents used a spare hand to restrain their dogs while braking and 19 percent used a hand to keep their dogs out of the front seat.

These behaviors can distract drivers and increase the risk of a crash. The AAA Foundation for Traffic Safety found that looking away from the road for only two seconds doubles the risk of an auto accident. The report noted that 56 percent of dog owners have driven with their pets at least once a month in the past year. Failing to restrain dogs while driving is an obvious threat to the dogs’ lives, but it is also potentially dangerous for anyone else in the car.

An unrestrained 10-pound dog in a crash at only 30 mph will exert roughly 300 pounds of pressure, while an unrestrained 80-pound dog in a crash at only 30 mph will exert approximately 2,400 pounds of pressure, a AAA spokesperson noted in a press release.

The survey was conducted among 1,000 dog owners who drove with their pets over the last year. While 83 percent acknowledged that an unrestrained dog in a moving car can be dangerous, only 16 percent currently use a pet restraint. A variety of such products are available to keep pets safe and help dog owners reduce potential distractions caused by pets while driving.

For more on “The 2011 AAA/Kurgo Pet Passenger Safety Survey,” visit

— Researchers: AAA and Kurgo, Salisbury, Mass.

Major Growth Projected in Mobile Transit Ticket Sales

Half a billion people worldwide will use their mobile devices as travel tickets on public transportation systems by 2015, more than five times as many as did in 2010, according to new forecasts from the English business research and consulting form Juniper Research.

While mobile ticketing has been in existence for several years in Japan and large cities in Scandinavia and Central and Eastern Europe, the report predicts that recent momentum in Near Field Communications (NFC)—technology that enables phones to interact with other electronic devices and images on printed materials from a short range—will add to market growth. As metro authorities begin the transition to open contactless payment systems, NFC ticket usage is forecast to grow significantly beginning in 2013. Furthermore, mobile ticketing also has growth potential with air travel, driven by mobile-delivered, bar-coded boarding passes.

Among other key findings from the report, Western Europe and the Far East & China are projected to be the leading mobile ticketing regions by volume in 2015. Also, poor user experience from problems such as bar code reading issues was cited as an obstacle to implementation.

A white paper and further details on the study, “Mobile Ticketing for Transport Markets: Airlines, Rail, Metro & Bus 2011-2015,” are available at

— Researchers: Howard Wilcox, Juniper Research.

Fatal Crashes Fell to Record Low in 2010

Traffic fatalities in 2010 fell to the lowest levels since 1949, despite an increase of nearly 21 billion miles in vehicle miles traveled by Americans during the year, according to a National Highway Traffic Safety Administration (NHTSA) report.

The number of traffic fatalities fell 3 percent between 2009 and 2010, from 33,808 to 32,788. Since 2005, fatalities have dropped 25 percent, from a total of 43,510 fatalities in 2005. There were an estimated 1.09 fatalities per 100 million vehicle miles traveled in 2010, down from the 1.13 fatality rate for 2009.

A regional breakdown showed the greatest drop in fatalities occurred in the Pacific Northwest states of Washington, Oregon, Idaho, Montana and Alaska, where they dropped by 12 percent. Arizona, California and Hawaii had the next steepest decline, nearly 11 percent.

However, some of the country’s most heavily trafficked regions did experience increases. New England saw an 18 percent rise in fatalities, while the Great Lakes region from Minnesota to Ohio rose 3.9 percent.

In a press release, the U.S. Department of Transportation (USDOT) credited the gains in part to a comprehensive national approach to reducing roadway fatalities that involves promoting strong traffic safety laws, high-visibility enforcement campaigns such as Click It or Ticket, rigorous vehicle safety programs and public awareness campaigns. The USDOT also noted that the Federal Highway Administration’s incorporation of new technologies such as Safety Edge—which reduces drivers’ risk of running off the road by shaping pavement edge—and safety features like rumble strips and cable median barriers in new road projects has also been effective.

The report, “Early Estimate of Motor Vehicle Traffic Fatalities in 2010,” can be viewed in its entirety at

— Researchers: The National Highway Traffic Safety Administration (NHTSA) National Center for Statistics and Analysis.

Stop-Start Vehicle Sales Projected to Far Outpace Hybrid EVs

A report from the clean technology market research firm Pike Research projects that one-third of all light-duty vehicles sold a decade from now will be stop-start vehicles, rising from 3 million units in 2011 to 37.3 million units per year by 2020.

Stop-start vehicles (SSVs) enable gasoline engines to turn off when vehicles are slowed down or stopped. SSV sales have been boosted worldwide largely by an effort to meet mandated carbon emissions reduction goals for vehicle fleets, according to Pike. SSVs are also commonly called micro hybrids, idle stop vehicles, or a variety of technologies branded by automakers.

The vehicles are estimated to provide 5 percent to 10 percent reductions in both fuel consumption and CO2 emissions. SSVs require more robust batteries and starter systems than are found in internal combustion engine vehicles and are more expensive, but cost considerably less than hybrid electric vehicles.

Pike’s analysis indicates that Europe has seen by far the greatest selection of vehicles with stop-start technology and the greatest volume of vehicles sold. North America has experienced a relatively slow penetration of the technology due to less stringent emissions reduction goals and other factors, according to the report. Although the technology is not as well known in North America, the report notes that SSVs are already outselling hybrids globally, with 3.5 vehicles expected to be sold in 2011 for each hybrid. That gap was forecasted to widen to a 16 to 1 ratio by 2017 because of the lower cost of SSVs compared to hybrid electrics.

More information on the report, “Stop-Start Vehicles,” is available on the firm’s website,

— Researchers: John Gartner, Pike Research.

Data Shows U.S. Congestion Increase in 2010

A report by INRIX showed that congestion increased nationwide for 11 consecutive months in 2010, particularly in the largest metro areas. The traffic data company speculated that population growth and a rise in interstate commerce brought on by the mending economy were the cause.

Seventy of the 100 largest U.S. cities experienced increases in traffic congestion. The top 10 most congested U.S. cities were determined to be: Los Angeles, New York, Chicago, Washington, D.C., Dallas, San Francisco, Houston, Boston, Philadelphia and Seattle. Increases of almost 20 percent in New York, San Francisco and Philadelphia were attributed to rebounds in the technology, healthcare, manufacturing, freight movement and services sectors that are the backbone of these local economies. The report estimated that Los Angeles’ freeway system was more congested than any other city in the U.S., U.K., France, Germany, Belgium or the Netherlands.

Americans traveling the nation’s worst traffic corridors experienced up to 80 hours of delay annually on the afternoon commute alone. Over 500 miles of roads were congested 25 hours a week or more, and nearly 200 of those miles were congested 40 hours a week or more—higher than any previous year.

The following were among the other findings to emerge from the analysis:

  • Worst/Best Weekday for Traffic: Thursday/Monday
  • Worst/Best Weekday Morning: Tuesday/Friday
  • Worst/Best Commuting Hour: Friday 5-6 p.m./Friday 6-7 a.m.

The Annual INRIX Traffic Scorecard is based on analysis of raw data from INRIX’s own historical traffic database generated by more than 4 million GPS-equipped vehicles traveling the roads each day, including taxis, airport shuttles, service delivery vans, long haul trucks as well as consumer vehicles and mobile devices. The full 166-page “INRIX National Traffic Scorecard” report is available for download at

— Researchers: Rick Schuman, INRIX vice president of public sector.

Compacts Rather than Hybrids, Electrics

Although high gasoline prices are driving strong sales of fuel-efficient compact cars, that demand hasn’t yet translated into major growth for electric and hybrid vehicles or subcompact cars, according to an analysis of recent statistics by GfK Custom Research North America’s Automotive sector.

As of May, when national gas prices hovered around the $4 mark, compact cars accounted for 18.1 percent of six-month light vehicle demand compared to 3.6 percent for smaller subcompact cars, such as the Honda Fit or Hyundai Accent. Alternative energy vehicle demand represented 9.4 per- cent of light vehicle demand, about half of the demand for compact cars like the Ford Focus or Honda Civic. GfK’s researchers contend that demand for hybrids and electrics is hindered by three major obstacles—lower familiarity, higher purchase prices and lack of convenience.

“For the average consumer looking to purchase a new vehicle, especially during these times of rising gas prices, they see more value in smaller vehicles with traditional gas engines—some of which approach 40 mpg—rather than hybrids or even electric vehicles,” GfK Senior Vice President Doug Scott said. “However, while consumers are looking at smaller vehicles due to high gas prices, they aren’t willing to go all the way down to a subcompact car. Consumers are discovering that newer compact cars offer the comfort features before only reserved to larger cars, combined with the fuel economy that was only available in much smaller cars.”

GfK also identified the factors that automakers must overcome to move buyers towards purchasing hybrids and electrics. Automakers should focus their marketing strategies on communicating the environmental benefits, while also addressing the obstacles consumers face with purchasing the vehicles.

More on GfK’s “Automotive Intentions and Purchases Study” can be found at

— Researchers: GfK Automotive, New York City.

Study Estimates Public Health Costs of Traffic Congestion

A study by Harvard University researchers estimates that the additional fine particulate matter emissions produced by traffic congestion in the nation’s largest urban areas lead to more than 2,200 premature deaths and $18 billion in related public health costs in the U.S. last year.

The public health toll of traffic congestion was estimated to be highest in some of the nation’s largest urban areas. The Los Angeles area was first, with an estimated additional 426 premature deaths and $3.3 billion in public health costs. It was followed by the New York City metro area (337 premature deaths, $2.6 billion), the Chicago area (251 premature deaths, $2 billion) and the San Francisco area (124 premature deaths, $1 billion).

On a positive note, the study noted that the number of additional premature deaths and public health costs due to traffic congestion has been on the decline because older, more polluting vehicles are being replaced with today’s low emission vehicles. The public health cost of traffic congestion in 2000, the Harvard researchers estimated, was approximately 4,000 premature deaths with a monetized public health cost of approximately $31 billion. They forecast that the toll in 2030, absent remedial actions to significantly reduce traffic congestion in the U.S., will be 1,900 premature deaths and $17 billion in social costs.

“Our estimates of the total public health costs of traffic congestion in the U.S. are likely conservative,” the authors wrote. They noted that their research considers “only the impacts in 83 urban areas and only the cost of related mortality and not the costs that could be associated with related morbidity, health care, insurance, accidents, and other factors.”

The authors also acknowledged some clear limitations to their research. Perhaps most significant, the results assume that the roadway and public transportation capacity would remain at 2005 levels while the population continues to increase out to 2030, a scenario that would mean worse than likely congestion.

The study, “The Public Health Costs of Traffic Congestion: A Health Risk Assessment,” was published in the scientific journal Environmental Health. The full report can be viewed at

— Researchers: Jonathan I. Levy, Jonathan Buonocore and Katherine von Stackelberg, Harvard University.

Rural Access to Intercity Transportation Has Declined, BTS Reports

As many as 3.5 million rural residents lost access to intercity air, bus, ferry, or rail transportation between 2005 and 2010, dropping the rate from 93 to 89 percent, according to a new report from the U.S. Department of Transportation’s Bureau of Transportation Statistics (BTS).

The BTS defined access to transportation as living within 25 miles from a small airport, bus station, ferry terminal, or rail station providing intercity service, and as 75 miles from a medium- or large-hub airport. Of the 71.7 million rural residents retaining access in 2010, 3.7 million lost access to more than one intercity transportation mode during those five years.

The report noted significant changes to several modes from 2005 to 2010, including bus service reductions by Greyhound and the suspension of the New Orleans– Jacksonville route previously provided by Amtrak’s Sunset Limited. According to the BTS, intercity bus transportation provided access to 78 percent of rural residents in 2010, more than any other mode, but fell from 89 percent in 2005. Air service coverage remained unchanged at 72 percent, while intercity rail access declined from 42 percent to 40 percent of the rural population.

All rural residents in Connecticut, Delaware, Massachusetts, New Jersey and Rhode Island had access to at least one intercity public transportation mode in 2010, as they did in 2005. North Dakota had the lowest percentage; 52 percent had access to at least one mode in 2010, down from 59 percent in 2005. Alabama faced the largest decline between 2005 and 2010 in the number of rural residents with coverage, from 94 percent in 2005 to 65 percent in 2010.

Nationally, rural residents had the following access to intercity transportation in 2010: one mode only, 15.7 million; two modes, 29.1 million only; three modes, 25.3 million; four modes, 1.6 million; no access, 8.9 million.

The report, “The U.S. Rural Population and Scheduled Intercity Transportation in 2010: A Five-Year Decline in Transportation Access,” can be viewed here.

— Researchers: Theresa Firestine, the Bureau of Transportation Statistics (BTS) of the U.S. Department of Transportation Research and Innovative Technology Administration.

Car Subsidy Schemes, Trade-Ins have Tradeoffs

A recent international study concluded that car fleet renewal programs introduced in the U.S., France and Germany fell short of their intended impact on environmental and safety objectives. The study, published by the International Transport Forum, focused on the effects that each program had on CO2 and NOx emissions from trading 2.8 million old cars in for newer vehicles. The report also assessed the monetary value of the different schemes and identified critical design elements for ensuring success in meeting the environmental and safety objectives.

The U.S. program, the Car Allowance Rebate System (CARS), also known as “Cash for Clunkers,” had positive results with regard to improved fuel economy, but failed to achieve improvements in fuel consumption and pollutant emissions, according to the report. The German program had larger-scale participation, but minimal effectiveness due to a greater share of smaller vehicles being traded in for larger vehicles. Meanwhile, the French program benefited from imposing restrictions wherein older, heavy CO2 emitters were traded for newer, more efficient vehicles. However, this led to a higher share of new diesel vehicles, which strongly limits lifetime NOx benefits.

The cost-effectiveness portion of the study compared the monetary cost of destroyed assets to the societal cost, which accounted for CO2 and NOx reductions and safety (avoided injuries and casualties). With this approach, Cash for Clunkers was relatively the most cost-effective, with an 80 percent cost recovery. The German program recovered only 25 percent of its cost while France’s recovered about 45 percent of its costs.

While all three programs helped reduce CO2 emissions, the report concluded that the monetized value of that impact was small: less than $7 million in the U.S. and less than $14 million in France and Germany. The monetized impact on NOx emissions was significantly higher, reaching about $430 million in the U.S., $430 million in Germany and $144 million for France.

In terms of road safety, the car renewal program estimated avoiding 40 fatalities and 2,800 serious injuries in the U.S. For Germany, the estimated impact was 60 deaths and 6,100 serious injuries avoided and in France, 330 injuries and 20 fatalities avoided.

The full report, “Car Fleet Renewal Schemes: Environmental and Safety Impacts,” is accessible online at

— Researchers: Filipe Fraga, TNO, Netherlands; International Transport Forum, Paris; Organisation for Economic Co-operation and Development (OECD) Environment Directorate, Paris

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