by BEN BROESAMLE

Sustainable Urbanism: development and transportation practices based on a long-term economic model that accounts for the costs of their ecological effects. Future urban sustainability requires a holistic consideration of our ideas about the relationship between the built environment and mobility. Ultimately, that means we must reconsider parking.

Consider Seattle’s urban future in light of the following estimates:

1. Population Growth. There are no official Seattle-only population forecasts, but we can extrapolate from recent history. According to Environmental Systems Research Institute, Inc. (ESRI), the City of Seattle gained 17,355 people between 2010 and 2012. A Census Bureau estimate puts the gain at 25,875. Assuming that ESRI’s nominal figure is the constant biannual growth rate, that’s 156,195 new residents by 2030. If this estimate is accurate, Seattle faces a projected growth pressure of nearly twenty-five percent over eighteen years. How will we move these people? Where will we house them? How will we make Seattle an increasingly walkable, enjoyable, activity rich, sustainable, economically successful and economically diverse place to live? Our answers to these questions will determine whether Seattle is a sustainable city going forward.

2. Mobility Spatial Efficiency. According to the Institute of Transportation Engineers (ITE), typical on-street auto parking requires 200 square feet of space per vehicle, exclusive of right-of-way for maneuvering; a parked car in a garage takes up 300-450 square feet depending on the specifics of maneuvering aisles and structural design. On the other hand, a seated human using public transit or a bicycle consumes about twelve square feet. This comparison demonstrates how private cars steal precious space from the urban fabric of a sustainable and growing city. A study shows that cars are parked ninety-five percent of the time. Do we really wish to incur the costs of allocating at least two-hundred square feet of our city’s built environment for each usually-parked private car when only twelve square feet are needed for each resident to be comfortable and highly mobile?

Let’s imagine that half of these 156,195 additional residents by 2030 brought a car with them: 78,097 cars. According to ITE standards, we would need to allocate approximately 200 square feet to park each one in on-street parking spaces. To park them would require 358 acres of parking spaces—imagine a square lot composed entirely of parking the length of thirteen football fields on each side. If we leveled downtown Seattle and paved everything from James Street to Olive Way, from First Avenue to Summit Avenue, that entire area could be covered with the added cars. Scarce space in our built environment has more valuable purposes than storing seldom-used assets, especially in places where we concentrate sustainable mobility investments. Seattle, like many other cities, faces a stark choice: park more cars or have active, walkable, aesthetically pleasing, sustainable urban environments.

To fit more people, more activities, and more economic drivers into the same space comfortably we must enable people to live comfortably and conveniently without a private car. Doing so recovers 200-450 square feet of space per adult currently under-utilized as car storage. We can use that space gained for human-oriented activities: sidewalk cafes, parklets, housing, and activated space inside buildings. People already demand those spaces in our urban villages and urban centers through their willingness to pay higher rents. Further, by focusing development on people, not underutilized cars, we can save on overall development costs.

I propose that ‘urban villages’ are the places to start. If we want to live in an ‘urban village’ that is within ¼ mile of a frequent transit stop, in an ‘urban center’, in a station area overlay district, in an area where there is a lot to do and a lot of people to meet and where there are cycle tracks, parklets, and side walk cafes, then we should consider the idea that what we want is to live without the car-related infrastructure that steals precious space from our happiness, comfort, and convenience for something we use only five percent of the time. Those who want a personal private car could choose to live in Seattle’s other wonderful neighborhoods or to rent unbundled, monthly parking in a commercial parking structure located on the periphery of the urban village or the quarter-mile (5-minute) walkshed around transit stations, and pay market rates that recover the costs of building and maintaining that parking space.

As a commercial mortgage loan underwriter I know two things. 1) The cost of parking is a loss leader for development given the present rates most apartments charge for subterranean parking spaces. In urban and CBD areas off-street parking generally requires over $200 per month in income to break-even. 2) Banks aren’t exactly visionaries and at times neither are developers. Their primary worry is risk: before this decade, there was a risk that no one would want to live, work, or shop in buildings without parking. It’s becoming increasingly clear that Millennials want to live without the hassle of owning a car and still have convenient, reliable, rapid mobility options. Boomers, while far more attached to their cars as a generation, will likely drive less with age.

Seattle zoning regulations already allow this convenient, sustainable lifestyle. New commercial and multi-family residential developments without parking are permissible under Seattle zoning code, in an ‘urban village’ that is within ¼ mile of a frequent transit stop, in an ‘urban center’, or in a station area overlay district (see: Seattle Municipal Code, Tables A & B for 23.54.015, sections II). Still, developers often over-park their developments in the belief that units will be more marketable, in order to obtain financing from risk adverse lenders or because they don’t fully realize what the market trends are. Currently, developers typically build about one parking space for every two apartments in the Belltown Urban Village and Denny Triangle Urban Village of the Downtown Urban Center. If we think this is a good idea, we’re not thinking ahead.

What will residents do without private cars if we still haven’t finished our Seattle Subway network, if bicycles and walking won’t do, and if buses don’t serve our destinations? In fact, we already have alternatives. Instead of parking privately-owned cars in our new, close-in, human- and transit-oriented developments, we can substitute off-street parking for private cars with reserved spaces for car sharing services such as Zipcar and Car2Go, spaces that could even serve electric vehicles.

According to Zipcar, one shared car can replace fifteen privately-owned cars. Car sharing reduces the required parking for 105 single-person apartment units to 7 spaces, with cars serving as a supplement other transportation modes. Removing personal private-car parking in favor of car-share spaces frees up fourteen out of fifteen off-street parking spaces for other uses, increases mobility choices, reduces negative externalities, increases the amount of active space in new buildings, and creates more sustainable neighborhoods with easy access to sustainable mobility.

As a matter of policy, if a developer wants to build a new building in an ‘urban village’ that is within ¼ mile of a frequent transit stop, in an ‘urban center’, or in a station area overlay district then that developer should only be allowed to provide at most on- or off-street parking for share-cars, bicycles, and handicapped, essential service, and commercial delivery vehicles. By removing personal private-car parking in favor of car-share spaces we can reactivate the gained space for more sustainable uses, uses that prioritize people over cars.

I believe we can build a successful, sustainable Seattle. Most of the regulations and opportunities are already in place. The Puget Sound Regional Council has even produced a “Parking Management Plan Checklist for Regional Growth Centers” (2003) that begins to move towards some of what is discussed here, including thinking long-term about urban development, providing for bicycles, encouraging shared parking, unbundling parking, moving parking away from centers, and preferring carpools, rideshares, and (by extension) car sharing. While most developers may not have caught on yet, Seattle is ready. We can grow sustainably and compactly without the negative effects of more privately-owned cars. It’s simple. It’s all about the parking.

Ben Broesamle is an aspiring real estate development and investment leader specializing in human- and transit-oriented development. He presently works as an analyst in commercial real estate finance and is on the board of Seattle Subway. He holds a BA in geography from UCLA where he concentrated in urban and regional development studies and minored in environmental studies. He moved from Los Angeles to Magnolia in 2010 where he now commutes via the 33 or 24.