Car Sharing (PDF)

Example: Boston’s Proposed Comprehensive Car Sharing Strategy (MA)

Summary: The easy availability of shared cars in transit-rich neighborhoods and transit-oriented developments may reduce automobile usage and ownership and allow residential developments to be built with fewer parking spaces.

Car sharing organizations, which may be non- or for-profit, distribute cars around a city or region for the use of their members. Members have access to a fleet of vehicles for short term use, allowing them to either supplement their own vehicles or choose not to own an automobile. Studies show that car sharing reduces vehicle travel and ownership. One study of San Francisco’s City CarShare program found that nearly two-third of members lived in zero-vehicle households and nearly 29 percent had gotten rid of one or more of their cars (Cervero, 2009). Zipcar, the largest car sharing company in the US, reports that 90 percent of members drove 5,500 miles or less per year and that its members report a 47 percent increase in public transit trips after joining.

Several transit-served cities encourage provision of parking spaces for car sharing in residential developments and some even allow the developer to reduce the required amount of parking to be provided for residents. As part of the development review process in Boston, Massachusetts, for example, the number of parking spaces that can be provided in ownership developments near transit is frequently restricted and the developer is required to provide parking for one or more car sharing vehicles to reduce the risk that resident households with more than one vehicle will park on neighborhood streets. Seattle’s zoning code grants reductions in minimum parking requirements for multi-family developments that allow dedicated, on-site parking for the city’s recognized carsharing operator. Rich Sorro Commons in San Francisco’s Mission Bay was permitted to provide only 85 parking spaces for its 100 affordable housing units due to a combination of its excellent proximity to transit, provision of below-market units to tenants less likely to own a car and provision of two parking spaces for City CarShare ((EPA, 2006).

The City of Boston may soon move forward with a comprehensive proposal, developed by the mayor’s Climate Action Leadership Committee, to maximize car sharing by Boston residents. The goal is to “ensure that every Boston resident lives within one-quarter mile of a shared car by 2020.” The Boston area is home to Zipcar, which has more than 18,000 members and 450 cars in Boston. The committee decided that “ensuring citywide access to shared cars is, therefore, a potentially powerful way of reducing vehicle miles traveled while ensuring that Boston residents have access to cars when needed.” The strategy for citywide access to shared cars involves actively promoting car sharing through a partnership with one or more shared-car companies; working with community-based organizations to promote car sharing, particularly in neighborhoods where market demand may not yet exist; revising zoning laws as necessary to allow for shared car parking as of right throughout the city; and creating opportunities for placing shared cars on municipal property.

Cervero, R. (2009). TOD and car sharing: A natural marriage. Access, 35, 25-29.

Environmental Protection Agency. (2006). Parking spaces/Community places: Finding the balance through smart growth solutions.