800 million parking spaces can be wrong

Civil engineers from the University of California, Berkeley, looked into how many parking spaces have been built in the US, and the most likely estimate is 800 million. Assuming each parking space is 200 square feet (10 by 20 feet is the standard), that amounts to 160 billion square feet or 3.67 million acres of concrete and asphalt. The mind boggles.

"Estimating the environmental cost of all that parking reveals that parking alone adds 10 percent to the CO2 emissions of your average automobile," Scientific American reports. "And the amount of soot added to the atmosphere as a result of all our cars nearly doubles. That's thanks to all that asphalt and concrete and the emissions that go along with making it."

The authors of the study note: "The environmental effects of parking are not just from encouraging the use of the automobile over public transit or walking and biking (thus favoring the often more energy-intensive and polluting mode), but also from the material and process requirements in direct, indirect, and supply chain activities related to building and maintaining the infrastructure."

The Infrastructurist reports that "over the course of a car’s lifetime, emissions of sulfur dioxide and soot rise 24 percent and 89 percent, respectively, once parking is properly considered."

"Those are just part of a broad “suite of impacts” that includes previously studied costs like the “heat island effect” — the term for when dark pavement raises the temperature of a city, leading to additional energy demands for cooling. And atmospheric costs are only part of the suite. According to the paper’s lead author, Mikhail Chester, there may be a larger infrastructure for parking than for roadways. If that’s the case, there would seem to be another great cost to all this parking: the relative cost of useful space."