By Earl J. Ritchie, Lecturer, Department of Construction Management
In Houston, a quick way to get agreement in a conversation is to bring up the subject of traffic. You’ll almost certainly get comments about how bad it is and that it’s getting worse.
And it’s not anybody’s imagination. Statistics show that despite considerable expansion of the freeways and the addition of HOV, or high occupancy vehicle, lanes, commute times are increasing.
And the largest increase has come over the past few years.
Data from the Texas A&M Transportation Institute’s latest Mobility Scorecard illustrates the problem, and the cost in our daily lives. More than 2.4 million Houston-area commuters are trapped by congestion every day, costing the average commuter 61 hours a year in 2014. That’s up by almost one-third since 1982, when congestion cost commuters about 42 hours a year.
About half of that increase occurred between 2010 and 2013.
It’s not just Houston. Cities of all sizes from around the country have seen similar trends, as this graph from the Mobility Scorecard shows. It illustrates trends in traffic congestion in 471 urban areas.
But more than personal inconvenience is at stake. The institute reported that all this time in traffic adds up to $160 billion in additional costs nationally, or $960 per commuter in lost time and wasted fuel. The researchers project that will grow to $192 billion by 2020.
There is no shortage of literature extolling the virtues of mass transit, carpooling, bicycling and other alternatives to driving to work. Despite these virtues, and in spite of complaints about congestion and significant expenditures on mass transit ($69 billion in 2014, according to the Congressional Budget Office), we continue to not only drive to work, but overwhelmingly drive by ourselves.
Source: Fusion (Wile 2015)
There is a wealth of statistical analysis of U.S. and international driving habits. You can see how we drive by location, income level, ethnicity, age, gender, price of gasoline, state of the economy and virtually any other category you can imagine, but the literature does not have good agreement on why we choose to drive alone. Some articles attribute it to a preference for independence or convenience. Elon University economists Stephen B. DeLoach and Thomas Tiemann mentionedthe possible influence of the cultural trend described in Robert Putnam’s Bowling Alone. They also cite “assembly time,” effectively a measure of the added duration of commute, as a factor.
Cost of operation, including gasoline prices, is often cited as a factor, although this seems to have a minor influence.
Single driving increased from 1980 to 2000 despite a significant decrease in gasoline price. The flattening from 2006 to 2014 is likely partly due to gasoline prices, and partly due to the 2008 recession. The increased price did not materially change driving patterns.
Similarly, demographic factors, such as population density and length of commute, have some influence, but they do not change the strong preference for driving alone. The graphic below shows the fraction of commuters carpooling from the 2011 American Community Survey.
By way of scale, the value for Chicago is 8.6 percent; for Houston, it’s 11.1 percent. Nationally, almost twice as many people carpool as ride public transportation, although proportionately more commuters in a few densely populated cities, such as New York, San Francisco, and Chicago, use public transportation. Washington. D.C., Boston, Seattle and Portland stand out as having high public transportation usage relative to their population density. This suggests local attitudes can affect commuting mode.
Some insight into the psychology of commuters is provided by a 1976 study of ridesharing fromAbraham D. Horowitz and Jagdish N. Sheth. They identify differences in attitudes between solo drivers and carpoolers, with solo drivers perceiving ridesharing as significantly less convenient, reliable, pleasant and time-saving than carpoolers did. Interestingly, there was not a significant difference in perception regarding cost, energy use, traffic and effect on the environment. They conclude that arguments of cost saving and pollution reduction would have little influence on solo drivers.
Apparently, a significant majority of drivers perceive the convenience, independence and time savings of driving alone to outweigh cost and environmental considerations. This would explain why HOV lanes, expanded light rail, ride matching services and the numerous arguments for mass transit have not decreased single driving.
Drivers haven’t been convinced by the argument that increased carpooling and mass transit usage would decrease traffic and commute time.
Some environmental advocates want to raise gasoline prices, thereby forcing people to reduce automobile usage, citing the European model. Based on the evidence above, this would require a large increase and is not likely to be politically acceptable in the U.S.