The United States is utterly dependent on private cars. Every day, American cities are clogged with cars of suburbanites commuting into business districts and back out to suburbs. During the workday, cars in cities must be stored in downtown parking lots and parking garages. And because of the volume and dimensions of all the cars attempting to park, parking lots must consume enormous amounts of land in our cities.

Dedicating this excessive amount of land to parking lots has a number of detrimental effects on the physical design of American cities:

First, enormous amounts of land must be dedicated to parking cars rather than to serving people. It is taken as a matter of course these days that the land dedicated to many of the facilities people actually use (restaurants, offices, grocery stores, etc.), will be dwarfed by the parking lots those facilities must provide to support America’s automobile addiction. If we didn’t have to provide these parking lots, more space throughout our cities could be dedicated to the facilities we actually use.

Second, parking lots induce water runoff by replacing water-absorbent surfaces (grass, shrubbery or trees) with water-repellant surfaces (asphalt and concrete). Replacing absorbent surfaces with repellant surfaces greatly increases the cost of transporting runoff water to areas where it can be properly stored. Failure to channel runoff water into storage areas like retention ponds, swales or ditches can easily result in flooding. The localized flooding related to these water-repelling surfaces can contribute to larger flash floods, threatening public safety.

The amount of land consumed by parking lots often dwarfs the amount of land dedicated to human uses. Source: Google Earth

The amount of land consumed by parking lots often dwarfs the amount of land dedicated to human uses. Source: Google Earth

Thirdly, parking lots increase infrastructure costs by forcing the facilities humans actually use to be further apart from one another. For example, if a big box grocery store requires a 600-foot-wide parking lot, expensive water, sewer, stormwater, electrical, and gas lines must all be extended an additional 600 feet to arrive at the next store. If you consider a city-worth of stores, apartments, businesses and offices that all collectively provide on-site parking, the additional infrastructure that must be installed and maintained to service a city can quickly become financially unsustainable.

Autonomous vehicles may provide us with an opportunity to both reduce our reliance on private automobiles and parking lots. Autonomous vehicles could achieve this through a number of means:

First, autonomous vehicles will be able to drive away from their passenger’s final destinations to pick up new passengers. The effect of this will be a more efficient use of each automobile. Cars today sit unused an average of 95 percent of the time. Autonomous vehicles will be able to leverage that time to pick up other passengers. The overall effect of this could mean that many fewer vehicles can provide the same transportation services we have now. Therefore, fewer parking spaces will be needed.

Second, the consolidation of similar routes via autonomous cars or busses should additionally reduce the overall number of automobiles on the road. Because these shared autonomous rides will be far cheaper than owning a private car, many more people will choose to save money by pooling their trips with others instead of taking an individual car. By bundling trips together, autonomous bussing and carpooling should further reduce the cars and parking spots needed to serve the population.

Finally, when this reduced fleet of autonomous vehicles does need to park, each car will possess coordinated knowledge about where the ideal parking lot for its service is located. The vast majority of these parking lots should be located on the outskirts of downtowns, ready to serve rush hour customers in the morning and the afternoon. A small number of public parking lots will still exist within dense urban areas to serve off-peak customers, but the vast majority of parking lots in cities will become unnecessary.

When the demand for parking lots collapses, we will be left with a question: How should our cities utilize their existing parking lots once they are no longer necessary to facilitate transportation? What should America do with its vacant parking lots in life after parking?

Parks and Plazas

Savannah’s system of regular parks often serves as a public backyard for its dense downtown. Source: Alexander Dukes

Savannah’s system of regular parks often serves as a public backyard for its dense downtown. Source: Alexander Dukes

Perhaps the most straightforward way to transform a parking lot into an amenity more useful for humans is to simply transform it into a park or plaza. Savannah, Georgia is famously home to a park system that regularly spaces parks, gardens, and public squares within a rectilinear street grid. Savannah’s parks are not some frivolous amenity for the wealthy. Studies have shown that parks with greenery improve both public health and property values. Parks are an asset, while parking lots are a liability. It makes sense to replace America’s parking lots with gardens, yards, plazas, and parks.

To create these parks and plazas, cities will need to identify a regular spacing of parking lots to be converted. This will require planners to identify target parking lots roughly a quarter mile apart. A quarter mile distance will mean these parks will be about a five-minute walk from one another. Having so many parks in walking distance will establish a sense that every home, office, factory, and storefront has access to a public “backyard” of sorts. Generously providing space for pickup soccer games, a lazy Sunday grilling session, or just a place to chill with friends goes a very long way toward making dense downtown apartments more pleasantly livable. In fact, the quality of life improvements green parks provide are precisely the reason lands around parks are sold at a premium.

The Guardian has published a helpful design guide of sorts for parks and plazas, based on a soon-to-be published study by SWA Group. All of these ideas are compatible with the Strong Towns ethos of incremental development and New Urbanism’s tactical urbanism concepts. You can start building parks and plazas in your community’s empty parking lots today!

New Housing

Another use for these soon-to-be depreciating parking lots will be housing. Large parking lots next to significant retail facilities are the perfect place to site multifamily housing developments. Placing dense housing adjacent to retail improves the experience of both the housing residents and the retailers. Retailers gain a “captive audience” of shoppers, while the adjacent residents gain easy access to the goods and services they use daily. In addition, when more people live within walking distance of their daily needs, the need for transportation across town (via cars or busses) is greatly reduced. In short, building homes adjacent to retail is actually likely to further reduce car use and therefore compound the volume of parking lot space that can be repurposed.

Public Amenities

Many parking lots can also be repurposed to provide public amenities. This is especially true where housing and green parks are attached to an existing parking lot. Recreative facilities like public pools, tennis, basketball and urban soccer courts go well with apartment complexes and encourage kids and adults to engage in active socialization with one another. Public services can also be provided in these former parking lots. Imagine if afterschool programs for kids were run directly adjacent to where those same children lived. Picture small kindergartens, preschools and church programs taking place next to parks that double as platforms for recreation on the weekends. The synergies that arise from combining public amenities with parks and housing encourage people to get out of the house to mingle with their neighbors. Positive externalities like community groups, business deals, and friendships are born from this socialization and begin to establish the tight, personal bonds indicative of a strong town.

Recreational amenities can also play host to popular community events which increase the visibility and popularity of a city. Source:  Wikimedia Commons

Recreational amenities can also play host to popular community events which increase the visibility and popularity of a city. Source: Wikimedia Commons


Entrepreneurial Space

 Once green parks, housing, and public amenities have consumed much of the former parking lots in an area, it may be a good idea to set aside the remaining parking lots as incubator space for entrepreneurs. Starting a business is hard. Incubator spaces give the industrious among us a low-risk platform to give their business ideas a shot. Incubator spaces can take many forms: They can be a simple retail stand, or they can exist as office or industrial space where goods and services are produced. Don’t overthink it. This is especially true with respect to food retail. Much of the world’s people get along just fine being served meals and produce from open-air markets that are little more than stands. Communal kitchens, food storage areas, and restrooms can help allay regulatory fears around food poisoning. Of course, other incubators of entrepreneurial activity such as offices, markets for non-perishable goods, and “maker spaces” (wood/metal/art/design shops), are easier to administer.

Food truck parks provide small-scale entrepreneurs with a lower barrier to entry to the market and enhance the community’s quality of life by providing greater variety. Source:   Isaac Benhesed

Food truck parks provide small-scale entrepreneurs with a lower barrier to entry to the market and enhance the community’s quality of life by providing greater variety. Source: Isaac Benhesed


Case Study: Mount Holly Gateway

Let’s take a look at how we can put some of these ideas into practice. Mount Holly is a moderately sized town in central New Jersey. Mount Holly’s downtown is an active, pristine example of American colonial urbanism. Unfortunately, the western entrance leading to downtown Mount Holly is an un-inviting, mundane example of American car addicted development. It serves as a perfect example of how we can use the opportunity autonomous vehicles may provide us to repurpose wasteful parking lots. The before and after illustration below demonstrates how this might be accomplished:

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First of all, note how much more space in the Mount Holly Gateway plan is dedicated to human use than in the existing Mount Holly parking lots. Millions of dollars worth of developable real estate, park and plaza space has be reclaimed from parking stalls. Assuming the Gateway’s land use zoning permits the construction of residences above shops, retailers in the area should acquire a captive consumer audience ready to buy the products being sold just below their homes. Also, because the area is surrounded by acres of uninterrupted housing and bisected by major boulevards, retailers will have plenty of people to sell their products to people outside the Gateway. In fact, despite its age, this retail area is already well trafficked as it is.

The residents of Mount Holly Gateway and the surrounding area will also appreciate the parks and swimming pools in close proximity to their homes. All of these amenities are within a walking distance of five minutes or less, making them accessible to children without their parents acting as chauffeurs. Demand permitting, a small preschool or after school center could be constructed in any of the leasable spaces on the lot. I began my academic career in a Montessori preschool built into a similar development that was primarily intended for retail use. I’m sure my mom would have appreciated it if I could have walked home from school like she did as a kid.

All of those amenities will further draw in residents from the surrounding area to create an even more fertile for retailers and entrepreneurs. These are prime conditions to establish an entrepreneurial space. Because seasoned proprietors are going to demand the prime locations for their stores, I suggest establishing a space for entrepreneurs on the northeast corner of the Gateway (on the triangular lot) or the elongated, knuckled building attached to the parking lot on the western edge of the Gateway. This will provide budding entrepreneurs with a well-sited incubator space to test their business ideas. Once an entrepreneur’s business becomes successful they could potentially buy a lot to permanently establish their business in the Gateway, or move out of the Gateway to one of the commercial areas in close proximity.

Finally, note the parking lot in the northwestern corner of the Mount Holly Gateway. This parking lot is where autonomous cars will be staged to wait for customers when they are not in use. It is intended to be out of the way of the human activities, but still close enough to conveniently pick up people when they finish their grocery shopping or serve as an electronic designated driver for bar patrons. With this arrangement, the parking lot and the autonomous cars it will stow regulate the car to its proper place in society: a tool for transportation, rather than an unhealthy addiction.