THE BLOG
12/12/2011 06:04 pm ET | Updated Feb 11, 2012

The High Cost of Free Walking

"If you seek a plenty of parking, look about you." 

While Michigan is home to 14,037,931 off-street parking spaces, well more than 5,000 of these are within a half-mile of Comerica Park.  And while off-street parking accounts for 6.57% of urban land uses nationally, the area surrounding Comerica Park devotes 21.66% of its parcel area to public off-street surface parking lots.  These lots aren't without societal costs, however.  Numerous studies document the damaging impact of large surface parking lots on pollution levels, economic growth, the tax base, public health, and urban vitality.  Despite these impacts, however, the number of parking spaces in downtown Detroit has grown considerably over the last 20 years.  Three groups have contributed to this state of affairs: parking lot owners, local government officials, and those of us who park downtown.  I wanted to look in the mirror -- as a downtown parker -- and turn attention to those who use surface parking lots.

Using the final regular season Tigers game as my laboratory, I inventoried the cost of all the parking facilities in the hour before the game on September 28. That day offered a unique opportunity in that there were no other major events downtown, so the vast majority of those seeking parking were heading to a singular destination.  Using 2010 SEMCOG othroimagery and parking data, I was able to identify all of the parking facilities within a half-mile of the stadium, a rough estimation for a 10-minute walk.  The results of that survey paint interesting pictures about those who use downtown parking.

2011-12-12-Parking_Lot_Context_Map.jpg

In economic terms, downtown baseball game parking seems a perfect market.  The sellers offer relatively homogeneous products  (all of the lots I examined had an attendant, for example), buyers have perfect information (it is impossible to get to the most expensive lots without first passing a cheaper option), and no seller has a monopoly.  Given the similarities between all of the options, buyers presumably make their choice between lots on two inputs -- the cost and the distance to their destination.

As these two maps suggest, the relationship between price and distance is highly correlated -- the parking lots closest to Comerica Park were the most expensive, and those furthest away were the least expensive.

2011-12-12-Parking_Distance_Diagram.jpg

2011-12-12-Parking_Price_Diagram.jpg

In fact, the relationship between price and distance is relatively linear.  Parking lots of similar distances from Comerica Park had similar prices, even if on opposite sides of the stadium.

2011-12-12-Parking_Cost_Diagram.jpg

The most interesting thing about this pattern, however, is that the median fans valued their energy at two cents per stride -- $0.02 a yard.  A small minority of fans who paid a great deal of money -- $25 -- to park within a few feet of the stadium, however, biased the same numbers for the average fan.  The average fan valued their stride at nine cents.  Extrapolating from these numbers paints a dim portrait of fans, however.

2011-12-12-walkingdiagram.jpg

This seemingly inconsequential fact about metro Detroiters has significant implications for downtown parking, however.  Because those using downtown parking are seemingly unwilling to park at even a modest distance from their destination, parking lot owners are unable to consolidate into a smaller number of shared parking facilities.  For example, only a small minority of lots is able to serve attendees of both Comerica Park and Joe Louis Arena, creating a great deal of wasted parking when only one of the two is in use.  If attendees were willing to walk slightly further, downtown would need far fewer parking lots, because a smaller number of shared lots could service a greater number of destinations.

Next time you go out to the ball game, literally vote with your feet, and go for a walk to avoid the premium parking -- it'll benefit you, the environment, and Detroit.