Monday, January 25, 2010

The Right Question

A mentor of mine used to tell me that the secret to a successful investigation is to start by asking the right question.

"The research question", he'd state, "is the most important part of the research process."

Any doubt I may have had about this mantra was whisked away by The High Cost of Free Parking by Donald Shoup.  In writing this book, Shoup has done more to influence urban planning than almost anyone else alive.  Not surprisingly, many people consider him to be one of the most influential contemporary urban thinkers.

So what is so ground-breaking about this book?  Is it a formula for eliminating pollution?  Ending sprawl?  Perhaps, but it does so by looking at a simple, far-reaching facet of accepted planning and zoning. In this book Shoup challenges a central but hidden land-use policy, one that affects virtually every community in the country: the minimum parking requirement. This policy holds that it's the planner's responsibility to provide enough parking spaces to allow everyone to park for free, wherever they go.

I had the privilege of hearing Mr. Shoup speak at Yale University last week and was amazed at the turnout.  It seemed like parking would be too dry of a topic to pack a lecture hall, but the hall was full.  It was a who's who of Connecticut transportation nerds, myself included.  He is one of the most influential thinkers in the field - his book has planners and politicians everywhere suddenly rethinking policies that have been unchallenged since World War II. 

Minimum parking seemed like a very good idea at the time.  To many people, it still does.  Who doesn't love free parking?  And who likes searching for change among the grit and gum wrappers under the car seat to feed the meter, or initiating a panicked search through wallets to pay for the garage?  Nobody, which is why the idea of requiring developers and land owners to provide enough parking seemed so attractive.  For decades, this policy was untouchable and enshrined in the planning canon.

Mr. Shoup upended this thinking.  He asked the right question: "What is the cost of providing 'free' parking to everyone all the time?"  This question matters because we tend to assume that if we aren't visibly paying for something, then there's no cost.  This is, of course, ridiculous to assume.  None of us have received an invoice for the war in Iraq, but we all know that this military action isn't free.  It turns out that the cost of providing "free" parking is very high.  It pushes up land prices, it taxes storm-water systems, it uses up land that could be put to better use.  In a nutshell, free parking is very inefficient because everyone pays no matter how much or how little they use those spaces.

When I go to a store part of the money I spend there goes to cover the construction and maintenance of the parking lot, whether or not I've used it.  If I rent a condo with "free" parking, I pay for that parking with my rent and condo fees, whether I use each allotted space or not.  Parking has been an amenity we use without paying for so long that we've become blind to the absurdity. 

Imagine for a moment that instead of parking, air travel was required to be "free".  Imagine the government raising all our taxes to dramatically upgrade air traffic control, airports, and planes, and provide tickets to anyone. Picture major travel destinations being required to help provide free tickets to anyone who wants them; the cost would of course be passed along to the consumer in the form of much higher prices for meals, hotel rooms, and amenities.  What would you do?  Well, it's "free", so you'd fly.  Immediately, there would be a shortage of seats on airplanes, and we would eventually become unaware of the staggeringly high cost being paid by frequent flier and aerophobe alike.

This is how parking works now.  We all use it as much as we can because it we've already paid for it.  Therefore, it's always being used, so there's a constant clamor for more because there never seems to be enough.  By asking the right question, Shoup cuts through conventional thinking to show that free parking isn't really free at all, and that it actually wastes resources and space.  His solution is simple: Stop requiring developers to build parking they don't want to build and charge the market price for the parking that's available.

Shoup suggests charging a price high enough to occupy about 85% of existing parking spaces.  In other words, raise the price until about 15% of people who would normally park are deterred into making another arrangement.  This will result in an efficiently utilized parking system in which those willing to pay market price can quickly and easily find a spot.

This obvious solution eluded planners and policy-makers for decades.  It's because they were asking the wrong question, namely: "How much parking do we need for everyone to park for free?"  This is a doesn't work, because there is no such thing as free.  Somebody pays.  You pay, even if you never get a bill.  Shoup was able to see this solution simply by asking the right question: "What is the true cost of a parking space, and what should we charge people for parking?"

Despite being convinced by Shoup's theory and thoroughly enjoying the book, seeing him speak last week left me somewhat disappointed.  To be fair, Donald Shoup is an excellent and engaging speaker.  What disappointed me was the realization that Shoup had asked and answered one critical question but left its corollary wide open.  Shoup tells us how to price parking but not how much parking to build in a community.  A town could have 20,00 spaces priced for 85% occupancy or 5,00 spaces priced for 85% occupancy.  In both cases the town would be following his advice. But would either one would be optimal for the town's economic vigor, ease of movement, and efficiency?

Too many spaces, and you arrive at an urban wasteland that welcomes cars but repels people.  Too few, and businesses can't serve all their customers, residents circle the block in frustration, and traffic builds.  Although it is tempting to say "the fewer parking spaces, the better", it's just not practical.  Until our land use policies change to create communities less dependent on private automobiles, a certain amount of parking is necessary. 

So my question for Donald Shoup, and everyone else out there, is, "How do we decide how many parking spaces to build in a community?"


  1. This is kind of a top-down solution, but why not build significantly less spaces (say, 25% less + convert the old spots to greenspace), charge more for them, as Shoup suggests, and see what the results are. Adjust. Repeat.

    In other words, this is going to have to be a trial and error scenario which the general public will probably get frustrated with. Politicians and advocates like Shoup will have to try and convince them that it's necessary, which will not be easy, but certainly worthwhile.

  2. We have such an excess of parking spaces in our cities - the question is not how many to build, but how many to dispose of.