I recently (actually last July; parenting has done a number on my free time) read a book I’ve been meaning to get around to for a long time: Donald Shoup’s The High Cost of Free Parking. For me, that’s been one of those books where it comes up in conversation and then you have to add the disclaimer that you’ve never actually read it, you’ve just heard interviews with the author or whatever.
The central idea is pretty well covered by this seven-minute video:
But if you watch that and think, “That was interesting, but does it come in the form of a six-hundred-page academic text?” then I definitely recommend the book! More seriously, the book is worthwhile reading for anyone in fields related to urban development, and I’d recommend it for those interested in the topic in general if they’ve got the time for it. Shoup explains the topic in a deep and compelling way, and the book is pretty lively reading for its length.
The part of the book about how urban planners model parking demand was a really interesting case study in a failure of engineering design. Off-street parking requirements were designed with one priority above all: Avoid any burden on on-street parking. That means they’re designed to predict peak demand and overestimate that, based on factors that can be easily measured and known in advance. Planning standards ended up with these detailed formulas for estimating parking demand that model the actual factors involved very poorly. To the extent that these models are empirically validated before joining the pantheon of planning best practices, the validation is presented in a way that’s statistically misleading, if not outright academic fraud.
The book also presents interesting case-studies that make clear the negative externalities of parking policy. Even some cities end up dedicating vast amounts of their core space to parking, pushing apart destinations and making the built environment inhospitable. Furthermore, crowded free street parking often accounts for a substantial percentage of urban traffic, with negative effects on everyone.
It’s been encouraging to see some of Shoup’s ideas catch on. The idea of limiting parking requirements and allowing for the “unbundling” of parking and housing costs have definitely come up in development in my neighborhood (where public transit is good enough that people might get by without a car, or at least families might get by with fewer cars). It seems likely to me that offstreet parking requirements are a major government regulation that’s been driving housing prices up. I think an important way to make housing more affordable is to allow a wider variety of housing; people can buy housing more affordably if there’s something available with just the quantity of space that they need. Same goes for quantity of parking.
I also wonder how the adoption of these ideas will be affected by a trend in young Americans driving later and less, which is quite a strange trend given a built environment that’s so dedicated to cars. Some of that trend is due to easier access to on-demand transportation services. But some of it is children’s sphere of freedom diminishing to nothing (IRL anyways) and I’m not sure what effect that will have as those teens grow up.