Even major oil companies admit that we are reaching peak oil—the point when the maximum rate of petroleum production is reached and begins to go into an unstoppable decline. But one thing could, at least somewhat, mitigate that problem. We may have also reached peak car usage in our major cities.
A study (PDF) from the Curtin University Sustainability Policy Institute says that many cities—including Vienna, Zurich, Atlanta, Los Angeles, and Houston—have already seen a decline in car usage between 1995 and 2005. Driving rates in the U.S. did rise in 2010 by 0.7%, but the study's authors believe a number of factors could come together to decrease our overall car use: The first is that cities are hitting what's known as the Marchetti wall. Most people don't like having to travel more than an hour each way to work, and cities tend to not get larger than one hour via car in every direction. The growth of public transport and the reversal of urban sprawl have also played a role, as more people in concentrated areas leads to more central shopping locations. Cities have also seen the growth of a culture of urbanism, resulting in more people who enthusiastically take public transportation, walk, and ride bikes. There's also, of course, the rise in fuel prices, which is probably the largest factor.
If all of these factors actually do cause a dramatic decline in car usage, city planners will have to think more about factoring light rail, buses, cycling, and walking routes into their plans. The study's authors speculate:
Traffic engineers will need to fundamentally change their traffic models and their assumption that increasing road capacity is their main raison d’etre. Road diets and traffic calming will become the skill they need to lead with rather than being pushed into....Peak car use will generate a growing rationale for removal of high capacity roads and conversion of space to support transit, walking and cycling and the urbanism of the new city.
There's just one caveat: The study only looked at car usage patterns in Europe, North America, and Australia. In rapidly developing countries like India and China, car use is likely to grow for the foreseeable future. So while peak car use may be an an important factor for urban planners to consider, it isn't a reason to stop searching for alternatives to fossil fuels.