Negative Externalities: Guaranteed Parking
When we have guaranteed parking, we tend to drive more.
Comparing the driving habits of residents living in 2 NYC communities, transportation researchers concluded that 31 percent more Jackson Heights, Queens residents drive to work than car owners who live in Park Slope, Brooklyn. Even though the residents of Park Slope are more affluent and they own more cars, they seem to want to avoid the hassle of looking for a parking space or walking to a parking lot near home each day. You see, many residents of Jackson Heights have their own parking spots while most people who live in Park Slope do not.
Grocery shoppers living in dense urban areas respond in the same way to supermarket parking lots. Looking at only those food shoppers living within a half mile of the store, researchers observed how they got here. When the markets had large surface parking lots, they drove. If instead, the local market had less accessible or paid parking and was pedestrian friendly, more people walked. Interestingly, parking did not significantly affect store loyalty.
Perhaps confirmed by the recent sale of 2 Boston Back Bay parking spots for $560,000, we love guaranteed parking. But the results are congestion, pollution, less green space. Economists would call those costs negative externalities because they are experienced by individuals who do not create them. And, they are encouraged by the driving incentives generated by municipal parking regulations.
Or, we could graph the negative externalities of America’s Parking Requirements:
Sources and resources: Streetsblog.org is a treasure trove of ideas about city space. For my information on parking, I used this blog post, University of Pennsylvania Professor Rachel Weinberger’s 2008 paper and her recent study on supermarket parking. The parking map was from a DC streetsblog while the Boston parking space story was documented in this article. Finally, at econlife, we have looked at the high cost of free parking and free driving.