Too much parking hobbles America’s TODs

In July, the City of Seattle cut in half the volume of parking required in new developments within a quarter-mile of a light rail line, bus rapid transit route, or regular bus route that offers frequent service. The decision is the latest recognition by an American municipality that parking requirements need to be pared down, especially in areas where rail or bus service is frequent.

Seattle’s City Council authorized a 50 percent reduction in off-street parking in areas that are within a quarter-mile of a transit stop where there is generally service at least every 15 minutes.

Mike Podowski of the Department of Planning and Development said the reduction will:

• Make housing more affordable by reducing the amount of money that developers have to spend on land and structures for parking.

• Help meet the City’s environmental goals by reducing automobile use and thereby cutting carbon emissions.

Seattle has been paring down or eliminating parking requirements for years. The willingness to deemphasize parking has helped to reinforce City and King County initiatives aimed  at fostering compact development and improving the public transit network.

Transportation analysts such as Robert Cervero at the University of California, Berkeley, have found that in much of the US, high parking requirements pose an obstacle to transit-oriented development. “Are Suburban TODs Over-Parked?”—a study by Cervero, Arlie Adkins, and Cathleen Sullivan in a 2010 issue of the Journal of Public Transportation—concluded that many multi-family developments near rail stations have more parking than needed.

Cervero and his graduate assistants looked at multifamily housing in 31 TOD projects in suburban areas of metropolitan Portland, Oregon, and San Francisco’s East Bay that have rail service. On average, the projects contained 1.57 parking spaces per dwelling unit—31 percent more parking than recommended by the Institute of Transportation Engineers (an organization that is hardly a foe of asphalt).

When Cervero’s researchers counted the number of parking spaces occupied during peak times (in the wee hours of the morning, when the great majority of residents, and their vehicles, are at home) they found 27 percent of the spaces empty. On average, only 1.15 parking spaces per unit were occupied.
ITE has calculated that in suburban multifamily housing, there’s a need for 1.2 parking spaces per unit. Local governments, however, often require more. Cervero, in surveying parking requirements in transit-oriented multi-family housing in 80 US cities, discovered that on average, municipalities required 1.37 off-street parking spaces per one-bedroom unit and 1.61 spaces per two-bedroom dwelling.

Developers sometimes provide even more parking than the regulations demand. “In the past,” Cervero, Adkins, and Sullivan pointed out, “the Urban Land Institute recommended that suburban commercial projects be parked above conventional standards as a ‘marketing advantage’ and cautioned ‘when in doubt, over-build parking.’”

The expense of providing parking can be sizable. Podium, tuck-under parking or underground parking spaces can add upward of $60,000 to the cost of housing in expensive regions like the San Francisco Bay Area. “Excessive parking could explain why transit-oriented development (TOD) in the United States has often failed to yield hoped-for benefits, like substantial ridership gains, more affordable housing, and land conservation...,” Cervero’s suburban study suggests.

Potential remedies

Cervero has found that much of the parking desired by residents of transit-oriented developments is the result of residents’ reliance on cars for their non-work trips—shopping, going out to eat, and other purposes. One way to reduce the need for car ownership, the Cervero team suggested, is through establishment of car-sharing programs in neighborhoods where there’s rail service. If car-sharing services (such as Zipcar or City CarShare) were more widely available, some residents would probably shed one or more cars, they predicted. The researchers suggested that governments encourage or require car-sharing in locations near rail.

In the Fall 2009 issue of ACCESS, Cervero wrote that after the nonprofit City CarShare operated for four years, 29 percent of its members had gotten rid of one or more of their cars. TOD and car-sharing are, he said, “a perfect marriage.” Yet, he added, “Strangely, as of now, there are few TODs in the US with carsharing options.”

What might cities do to change this? They could, says Cervero, “play the role of matchmaker between TOD and carsharing” by allowing developers to provide a shared-car parking space instead of several private parking spaces.

Unbundling the cost of a private parking space from the cost of renting an apartment in the building would further reduce car ownership and increase the demand for shared cars,” he adds.

Through programs such as car-sharing, Cervero believes cities could get by with less off-street parking than the ITE recommendation of 1.2 parking spaces per multifamily dwelling.

Nearly 40 percent of the cities he surveyed allow developments to reduce their parking supply if they’re close to rail transit. Twenty-one percent of cities allowing variances permitted them for projects near a bus line.

The shorter the walk to a transit station, the more the parking demand usually falls. Consequently, says Cervero, there’s a strong case for “clustered development with good internal pathways that provide fairly short, direct connections to rail stops.” Liberty Station, a proposed mixed-use project in Libertyville, Illinois (see story on page 5), is one TOD in which efficient and comfortable pedestrian routes are being promised.

Another recommendation, from UCLA planning professor Donald Shoup: Allow TOD tenants to opt for deeply discounted transit passes instead of 300 square feet of pavement for vehicles.

Seattle’s shift

Ref Lindmark, a transit advocate in Seattle, says one aspect of his city’s parking policy that’s “a little more progressive” than those of most cities is its authorization of off-street parking reductions not just near rail transit but also near bus lines—including bus rapid transit (BRT) and ordinary bus routes. This policy, in turn, has been supported by public decisions to improve the routing of buses, he says. In recent years, a larger proportion of buses have been routed through neighborhood centers, making those mixed-use centers, in Lindmark’s view, “more transit-rich than they had been historically.” 

Seattle Council member Richard Conlin, who shepherded this summer’s changes through five months of public hearings, says 5,670 acres in the city had no minimum parking requirement for residential development as of early July. The new legislation adds about 540 acres.

The 50 percent reduction in required off-street parking applies to areas that are outside designated “growth areas” but within a quarter-mile walk of frequent transit. Thirty-nine of the city’s neighborhoods contain designated growth areas.

As for the central business district, Seattle has long been leery of superfluous parking there. Podowski notes, “There have been no residential parking requirements downtown since 1975.”