The High Cost of Free Parking: Updated Edition

by Donald C. Shoup

Requiring Peter to pay for Paul’s parking, and Paul to pay for Peter’s parking, was a bad idea. People should pay for their own parking, just as they pay for their own cars and their own gasoline.

Off-street parking requirements collectivize the cost of parking because they allow everyone to park free at everyone else’s expense.

Free parking gives the largest subsidy per mile to the shortest vehicle trips—the ones that, without a parking subsidy, we would most likely make by walking, cycling, or public transport.

Palo Alto, California, for example allows reductions of up to 50 percent in parking requirements if the difference is made up through a landscaped reserve. Not one of these landscaped reserves has subsequently been converted to parking.

How far is it from San Diego to San Francisco? An estimate of 632.125 miles is precise but not accurate. An estimate of somewhere between 400 and 500 miles is less precise but more accurate because the correct answer is 460 miles. Nevertheless, if you had no idea how far it is from San Diego to San Francisco, whom would you believe: someone who confidently says 632.125 miles, or someone who tentatively says somewhere between 400 and 500 miles? Probably the one who says 632.125 miles because precision creates the impression of certainty. ITE’s parking and trip generation rates illustrate a familiar problem with statistics used in transportation planning. Reporting data with extreme precision implies confidence in their accuracy, but transportation engineers and urban planners often report highly uncertain estimates as precise numbers. Placing unwarranted trust in the accuracy of these precise but uncertain data then leads to bad transportation and land-use policies.

Similarly, land uses don’t make vehicle trips; people make vehicle trips.

Reporting statistically insignificant estimates with misleading precision creates serious problems because many people rely on ITE manuals to predict how urban development will affect parking and traffic.

But as another great economist, John von Neumann, said, “There’s no sense being exact about something if you don’t even know what you’re talking about.”109

planners should also ponder this warning from Lewis Mumford: “The right to have access to every building in the city by private motorcar, in an age when everyone possesses such a vehicle, is actually the right to destroy the city.”112