Marcos Paulo Schlickmann, a transportation specialist and collaborator at Caos Planejado, our Brazilian partner website, recently interviewed Professor Donald Shoup, who answered questions about private and public Parking issues.

Private parking

Marcos Paulo Schlickmann: What is your opinion on legal parking minimums? 

Donald Shoup: In The High Cost of Free Parking, which the American Planning Association published in 2005, I argued that minimum parking requirements subsidize cars, increase traffic congestion, pollute the air, encourage sprawl, increase housing costs, degrade urban design, prevent walkability, damage the economy, and penalize poor people. Since then, to my knowledge, no member of the planning profession has argued that parking requirements do not cause these harmful effects. Instead, a flood of recent research has shown they do cause these harmful effects. Parking requirements in zoning ordinances are poisoning our cities with too much parking. Minimum parking requirements are a fertility drug for cars.

MPS: What would happen if we were to abandon parking minimums?

DS: Reform is difficult because parking requirements don’t exist without a reason. If on-street parking is free, removing off-street parking requirements will overcrowd the on-street parking and everyone will complain. Therefore, to distill 800 pages of The High Cost of Free Parking into three bullet points, I recommend three parking reforms that can improve cities, the economy, and the environment:

• Remove off-street parking requirements. Developers and businesses can then decide how many parking spaces to provide for their customers.
• Charge the right prices for on-street parking. The right prices are the lowest prices that will leave one or two open spaces on each block, so there will be no parking shortages. Prices will balance the demand and supply for on-street parking spaces.
• Spend the parking revenue to improve public services on the metered streets. If everybody sees their meter money at work, the new public services can make demand-based prices for on-street parking politically popular.

Each of these three policies supports the other two. Spending the meter revenue to improve neighborhood public services can create the necessary political support to charge the right prices for curb parking. If cities charge the right prices for curb parking to produce one or two open spaces on every block, no one can say there is a shortage of on-street parking. If there is no shortage of on-street parking, cities can remove the off-street parking requirements. Finally, removing off-street parking requirements will increase the demand for on-street parking, which will increase the revenue to pay for public services.

MPS: Is abundant and free parking at destinations an incentive for driving and a disincentive for using other modes?

DS: Consider the three main elements of city planning. First, divide the city into separate zones (housing here, jobs there, shopping somewhere else) to create travel between the zones. Second, limit density to spread everything apart and further increase travel. Third, require ample off-street parking to spread everything even farther apart and make cars the easiest and cheapest way to travel. Cities have unwisely adopted these three car-friendly policies. Separated land uses, low density, and ample free parking create drivable cities but prevent walkable neighborhoods. Although city planners did not intend to enrich the automobile and oil industries, they have shaped our cities to suit our cars.

Parking requirements in zoning ordinances are particularly ill advised because they directly subsidize cars. We drive to one place to do one thing, and then to another place to do another thing, and then finally drive a long way back home, parking free almost everywhere.

MPS: What is your opinion on park-and-ride programs?

DS: I think park-and-ride schemes are another way to subsidize cars. It would be better to devote the land around transit hubs to denser development. If parking is provided, it should be on the periphery of the development, not adjacent to the transit stop, so commuters walk past all the stores and restaurants on their way to and from their cars. And drivers should pay the market price for parking, so transit riders who don’t drive to the transit stations don’t have to subsidize the transit riders who do park at the stations.

MPS: Many employers supply a parking space for free for their employees. Why might this not be a good policy and what might be a suitable alternative?

DS: Employer-paid parking is an invitation to drive to work alone. It subsidizes many commuters who would have driven to work anyway, but it also persuades more commuters to drive to work alone instead of carpooling, riding public transit, biking, or walking to work.  A survey of 5,000 commuters and their employers in downtown Los Angeles showed that, on average, employer-paid parking stimulated a 34 percent increase in the number of cars driven to work.

In 1992, California enacted legislation that directly addresses the problems caused by employer-paid parking. California requires employers who provide a parking subsidy to employees to offer employees the option to choose a cash allowance to an employee equivalent to the parking subsidy that the employer would otherwise pay to provide the employee with a parking space.

The employer must offer an employee the option to take cash in lieu of a parking subsidy only if the employer makes an explicit cash payment to subsidize the employee’s parking. Therefore, the employer saves the cash paid for the parking if the employee takes the cash allowance instead. The employer’s avoided parking subsidy directly funds, dollar for dollar, the employee’s cash allowance, so there is no net cost for the employer when an employee forgoes the parking and takes the cash. The employer must offer the cash allowance only to each employee who is offered a parking subsidy. And each employee’s cash allowance is equal to the parking subsidy offered to that employee, so if some employees are offered smaller parking subsidies than other employees, their required cash allowance is smaller. Thus, the law is tightly written to avoid imposing a net cost on employers.

Giving commuters a choice between a parking subsidy and its cash value reveals that free parking has a cost—the foregone cash. Commuters who forego the cash are, in effect, spending it on parking. Employers can continue to offer free parking, but the new option to take cash instead of parking will increase the share of commuters who walk, bike, or ride the bus to work.

Case studies of firms that have complied with California’s cash-out law found that for every 100 commuters offered the cash option, 13 solo drivers shifted to another travel mode. Of these 13 former solo drivers, nine joined carpools, three began to ride public transit, and one began to walk or bicycle to work. Overall, the share of commuters who drove to work alone fell from 76 percent before the cash offer to 63 percent afterward. These mode shifts reduced vehicle miles traveled and vehicle emissions for commuting to the eight firms by 12 percent. This reduction in vehicle travel is equivalent to removing from the road one of every eight cars driven to work at the case-study firms. The larger shift to carpooling than to transit shows that parking cash out can work even in places with limited public transit.

More information about parking cash out is available at this link:  http://shoup.bol.ucla.edu/ParkingCashOut.pdf

Public parking:

MPS: Why shouldn’t public/on-street parking be free and how should it be priced?

DS: Charging too much or too little for on-street parking can cause a lot of harm. If the price is too high and many curb spaces are vacant, adjacent businesses will lose customers, employees will lose jobs, and cities will lose tax revenue. If the price is too low and no curb spaces are vacant, drivers searching for a place to park will congest traffic, waste fuel, and pollute the air. Consequently, the right price for curb parking is the lowest price that can keep a few spaces open to allow convenient access. This is the Goldilocks principle of parking prices—not too high, not too low, but just right.

With conventional parking meters, the price stays the same throughout the day but the occupancy rate varies. With dynamic parking meters, the prices vary but the occupancy rate stays the same—one or two spaces are open. Goldilocks prices will give all drivers great parking karma, and will guarantee front-door access to all businesses.

MPS: Please tell us a little bit about SFpark and smart parking systems.

DS: In 2011, San Francisco adopted SFpark, a pricing program that aims to solve the problems created by charging too much or too little for curb parking. In seven pilot zones across the city, with a total of 7,000 curb spaces, San Francisco installed sensors that report the occupancy of curb space on every block and parking meters that charge variable prices according to location and time of day. The meters were also the first in San Francisco to accept payment by credit cards, and this convenience provided good publicity for SFpark.

SFpark adjusts parking prices every six weeks in response to the average parking occupancy during the previous six weeks. If the occupancy rate on a block is higher than 80 percent during a time period (such as from noon to 3 pm), the hourly price of parking increases by 25 cents. If the occupancy rate is below 60 percent, the hourly price of parking decreases by 25 cents. Consider the resulting prices of curb parking on a weekday at Fisherman’s Wharf, a popular tourist and retail destination, after almost two years of price adjustments.

Before SFpark began in August 2011, the price for a space was $3 an hour at all times. With SFpark, each block can have different prices during three periods of the day—before noon, from noon to 3 pm, and after 3 pm. By May 2012, most prices had decreased in the morning hours. Some prices increased between noon and 3 pm—the busiest time of day—and most prices declined after 3 pm. Prices changed every six weeks, never by more than 25 cents per hour.

SFpark based these price adjustments purely on observed occupancy. City planners cannot reliably predict the right price for parking on every block at every time of day, but they can use a simple trial-and-error process to adjust prices in response to past occupancy rates. The only way to tell whether the price is right is to look at the results. Here is the link to a short article that explains how Sfpark has worked: http://www.uctc.net/access/43/access43_sf_park.pdf

MPS: How can we have a low-cost version of SFpark/smart parking systems for cities with low smartphones/credit card penetration such as in Brazil?

DS: The technology used for demand-based pricing in San Francisco is getting both cheaper and more sophisticated. Other cities will therefore find it easier to mount similar programs. Berkeley and Oakland in California have begun to charge demand-based parking prices with simple technology. Boston and Washington, D. C. have also begun to charge demand-based parking prices with newer and cheaper technology.

The results in Los Angeles and San Francisco show that cities can make huge improvements even without frequently adjusting prices in response to demand. Simply extending the operating hours for existing meters into the evening in places with high demand rather than turning the meters off at 6 p.m. is a demand-based strategy, and it does not require any new investment. The meters are already there, so they will reduce parking and traffic congestion and bring in new revenue without any new cost.

In downtown San Francisco, the people who beg for a living are out until midnight but the parking meters quit work at 6 p.m. Why not run the meters during the times of high parking demand in the evening and use some of the money to help the homeless? Similarly, cities can operate their meters during times of high demand on Sundays. If cities carry the argument for demand-based pricing to its logical conclusion, they can extend the hours of meter operation for as long as needed to manage demand, and thus provide large benefits where meters already exist. If cities continue to put their meters to sleep at 6 p.m. and on Sunday, they have learned little about demand-based prices for curb parking.

Parking was for many years the most stagnant industry outside North Korea. Now, however, nothing in parking is the last word for long. The parking industry is taking advantage of everything Silicon Valley has to offer, and the humble parking meter has improved rapidly in recent years. Meters now accept payment by credit cards and cell phones. They can charge different prices by time of day or day of the week, depending on demand. Parking officials can remotely reconfigure the price schedule in any neighborhood, and the new rates are sent wirelessly to all the meters in the neighborhood. They can be multilingual and guide the users through transactions, displaying messages such as “Please insert your card other side up.”

Parking occupancy sensors have also evolved rapidly. The first generation of sensors used in San Francisco and Los Angeles were embedded in the pavement and had to be dug up or abandoned when the batteries needed replacement, but new forms of occupancy sensing have developed. Some single space meters have occupancy sensors embedded in the meter heads, which lower the power requirements and simplify the battery replacement. Parking enforcement vehicles equipped with cameras to record license plate numbers can also count the number of parked cars. Fixed-mount cameras can also analyze parking occupancy.

The technology of metering and occupancy sensing is becoming cheaper and better so fast that programs like SFpark and LA Express Park will be much easier for other cities to adopt. We may soon consider coin-in-the-slot parking meters as primitive as the Wright brothers’ first airplane at Kitty Hawk.

MPS: Do you know any city that redirects part of the parking revenues to transit, public services, etc.? And do you know how much parking fees can be expected to contribute to pay the costs of those services?

DS: Most cities use their parking revenues to fund public services. San Francisco uses all of its meter revenue to fund public transit.  To create local support for user-paid parking in commercial areas, some cities have created Parking Benefit Districts that spend the meter revenue for public services in the metered areas. These cities offer each district a package that includes both priced parking and better public services. Everyone who lives, works, visits, or owns property in a Parking Benefit District can see their meter money at work, and the package is much more popular than the meters alone. Localizing the parking revenue will generate local support for the parking meters. Here is the link to a short article that explains the benefits of spending the parking meter revenue to finance neighborhood public services on the metered blocks: http://tinyurl.com/3vmvz

MPS: Some experts agree that a good public parking policy might replace or be as good as congestion charging. What is your opinion on this?

DS: The average car is parked 95 percent of the time, so if most parking remains free, most drivers will pay congestion tolls only during the brief time they are traveling between two free parking spaces.  Parking charges complement congestion tolls, and one study showed that parking fees and congestion tolls combined will make transportation more efficient than either one alone can (The High Cost of Free Parking, Chapter 7). When parking fees and congestion tolls are introduced together, both the optimal parking fee and the optimal congestion toll are lower than when either one is introduced alone.  But the study also found that parking fees alone produced 96 percent of the benefit that parking fees and congestion tolls together would produce, while congestion tolls alone produced only 72 percent of this benefit.  If a city had to choose either parking fees or congestion tolls, parking fees can produce higher benefits.

Here is the link to a series of short articles that explain all the parking reforms I recommend: http://www.shoupdogg.com/reforms/

MPS: How will autonomous cars impact public and private parking?

DS: Autonomous cars will be most valuable where parking is expensive.  All of parking reforms I recommend will shift the cost of parking to drivers and they will therefore accelerate the adoption of autonomous cars. So, if cities want to encourage autonomous cars, they should adopt the parking reforms that shift the cost of parking to drivers, where it rightly belongs.