A recent study by U.S. Pirg sheds light on a beneficial trend for energy security--decreased driving and car usage in America’s urban areas. Increasingly, Americans are seeking mobility options other than the passenger vehicle, and the research provides some quantitative insights into where, how, and why the nation’s driving habits are in decline. The findings show that in the nation’s largest metro areas, there has been an increase in the proportion of the workforce working at home, a decrease in commuting by private vehicle, a decrease in the number of households with two or more cars, and increases in biking, car-free households, and public transit miles per-capita. Perhaps most telling overall has been the decrease in per-capita vehicle miles traveled (VMT)—one of the surefire best ways to reduce petroleum consumption.
Pirg’s findings by the numbers:
- The average American drives 7.6 percent fewer miles today than when per capita driving peaked in 2004
- Between 2006 and 2011:
- Per-capita VMT fell in three quarters of the nation’s 100 largest urban areas
- The number of workers commuting via car fell by almost five percent in New York, Washington D.C., and Austin
- Transit passenger miles increased in 60 out of 98 of the nation’s largest urbanized areas
While this all bodes well for decreasing oil dependence, there is one problem: some of the study’s major findings don’t pass the sniff test. Specifically, the most significant declines in VMT per capita were in New Orleans, LA, Milwaukee, WI, Madison, WI, Harrisburg, PA, Pittsburgh, PA, and Poughkeepsie, NY.
Hmm. Ranked first on the list is New Orleans, which was devastated by 2005’s Hurricane Katrina. While the report's commentary does recognize this factor, stating “New Orleans has seen the largest drop in per-capita VMT—22 percent—since 2006, possibly a result of Hurricane Katrina,” a lack of controls on the data set implies that the findings shouldn’t be taken at face value.
The study also seems to gloss over key economic changes. While it states that “variations in the economy do not appear to be responsible for variations in the trends in driving among urbanized areas,” unemployment levels in many of the cities topping the VMT decline list have increased dramatically, far above the national average—a factor that the “straight face test” says probably weighed on driving rates.
According to the Bureau of Labor Statistics, national unemployment rose 83 percent during the period studied. While unemployment rose in all of the cities in question, some rose by far more than the national average (shaded red), suggesting that VMT declines in these cities is at least partially caused by economic decline. Furthermore, population growth in many of these cities was below the national average. The study states that growth in all the nation’s urban areas outpaced the average population growth of the entire country, with a 14.3 percent growth rate in urban areas between 2000 and 2010, compared to a 9.7 percent national average growth rate. This suggests a 1.43 percent annual population growth rate in the urban areas studied, and a 7.15 percent rate of growth in the general population during the period of research (2006-2011).
While the VMT decreases can’t be attributed to population decreases since they are calculated per-capita, lagging population growth is a known indicator of poor urban health—especially when the rest of the country is seeing increasing urbanization. Although the unemployment rates of Pittsburgh and Milwaukee increased by less than the national average, they also saw flagging population growth, suggesting gainful employment is scarce enough to drive people out of the city and making the city less attractive for newcomers.
Let's be clear: VMT declines are only a positive sign when they accompany economic growth.
Many of the Pirg study’s other findings are helpful, reporting increases in bike usage and telecommuting. However, the findings on VMT declines must be taken with a large grain of salt. This is not to suggest that some of the cities listed have not taken any measures to reduce vehicle miles traveled, but is designed to draw attention to the fact that falling VMT can often be a sign of economic decline. Although dynamics are gradually shifting, the longstanding trend in the United States has been one in which increased fuel consumption is associated with economic productivity—an unsustainable and problematic paradigm. Now, both technology and willpower exist to break away from this dynamic for the first time in the country’s history. However, the list of cities identified by Pirg don’t necessarily represent effective implementation of traffic management systems. Cities shouldn’t need to suffer through hurricanes, a 200 percent increase in unemployment, or zero percent population growth to reduce VMT.
However, after removing cities facing stagnant population growth and unusually high unemployment, two cities remain: Madison, and Tulsa. Madison is well known for its aggressive approach toward reducing congestion and fuel consumption, as city planners have invested in many innovative measures over the past decade to reduce the city’s traffic burden. Some of Madison’s approaches were profiled in SAFE’s previous reports, “Congestion in America
” and “Transportation Policies for America’s Future
,” which present research on how strategic transportation policies can reduce oil dependence and improve energy security. Some of the measures recommended include:
- Dynamic Tolling
- Urban Area Congestion Pricing
- VMT Pricing
- Intelligent Transportation Systems
- Public Transit
- Multimodal Urban Planning
Both reports offer a number of policy recommendations, as well as forecast oil savings with strategic implementation (see below). Continued work at both federal and local levels is needed to implement sound policy, to ensure VMT reduction can exist as part of robust economic growth.