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May 2, 2002
Photo by Doug Scott
Poulsbo Place, designed by Mithun, is a high-density infill development, within easy walking distance of downtown Poulsbo’s shops and waterfront.
Extending development into prime agricultural land, into flood plains and wetlands, into forest ecosystems, critical habitats, onto undeveloped land that does not have the ecological capacity to support it, squanders our common resources now and deprives future generations, which is the antithesis of sustainability.
In other words, if green buildings contribute to sprawl, then we are no farther ahead, building “little green islands in a sea of subdivided land,” as Jane Holtz Kay said. Sprawl, with its low density, single-use zones and maze of meandering streets that favor cars over pedestrians, swallows 1.2 million acres of farmland in the United States, 60,000 acres of wetland and converts 3 million acres of open space to 2 million homes per year. That is roughly 340 acres an hour at a gross density of less than one home per acre.
According to the Planning and Zoning News, land consumption is occurring at an unprecedented rate, estimated to be eight to 12 times faster than the underlying population and employment increase from 1970-90. Seattle is not exempt. Sixty percent of this region’s population growth during the 1990s was accommodated in low-density, car-dependant neighborhoods, according to Northwest Environment Watch.
New urbanism, when it arrived in the early 1980s, seemed poised to address the environmental problems of sprawl. Though the principles derived from promoting sociability and community, there were many environmental spinoff benefits.
Building compactly at higher densities reduces land consumption, minimizes the infrastructure costs and environmental damage of excess roads and utilities. The emphasis on a mix of uses within easy walking distances of residences provides the potential for residents to remain all day within their neighborhood, thereby reducing car use. The emphasis on proximity to public transportation serves the same purpose.
Given these benefits, most people would think that new urbanism and green development are two sides of the same coin. While many recent new urbanism developments incorporate green buildings, they have failed to achieve this potential in land planning.
Most of the new urban developments have been on greenfield sites, gobbling up forested land or farmland and are isolated from existing communities, services and from public transit. Some residents are faced with a 20-minute car ride to the nearest grocery store while they wait for higher population densities to support these retail services. New urbanists argue that growth will occur on these lands anyway, and by not building sprawl, a better environment will ultimately be created.
The rational grid of streets and alleys as the required framework of new urbanism is at odds with achieving more sustainable site development, particularly in the Northwest. While the street grid has many benefits — more efficient and denser housing lots for example — its implementation ignores existing topography.
Small building lots on gridded alleys and streets must be graded to 5 percent or 6 percent or less. In our hilly Northwest, large tracts of land are cleared of all vegetation and graded nearly level in order to achieve this perfect grid. This wholesale transformation of the environment to accommodate a rigid template is very similar in environmental impact to the sprawl that it is intended to replace.
Recognizing these shortcomings, the Congress for the New Urbanism has created an environmental task force to study environmental practices. However, the 2001 Congress meeting overshadowed these efforts, where new urbanists angrily vented their frustration at environmental regulation and environmentalists for compromising good development.
Urban designer Paul Murrain described wetland preservation and buffers as unnecessarily fragmenting neighborhoods and impeding the flow of the street grid and pedestrian movement. Stormwater detention and tree preservation, he said, reduces density, resulting in an anti-urban landscape.
“At what point does the sacrifice of sustainability attributes become justified by the benefits of new urbanism?” writes Daniel K Slone, co-chair of Environmental Solutions Group. “Or, at what point in the effort to achieve a sustainable project does the adoption of new urban design so compromise environmental sustainability that sacrifice of key new urban design elements is justified?”
The answer should be that good development does not compromise either. Sustainable new urbanism must preserve local natural capital, which enriches our communities as much as a sociable pattern of buildings.
Bending the street grid to adapt to local topography preserves trees and terrain without losing orientation or density. Orienting the grid to sun angles would allow for greater passive solar use. Planning for onsite infiltration with rain gardens to treat water where it lands improves community watersheds, saves on infrastructure costs and ties residential landscaping into natural systems in a way that gives it meaning beyond decoration. Respecting the value of wetlands as wildlife habitat and for the value it brings residents and developers, challenges the designer to strengthen the pedestrian and transit linkages around these features.
Growth will continue, but the challenge for land planners, designers and builders is to manage growth so that it creates viable human habitat without compromising our natural habitat. Why clear and level a greenfield site when there are numerous brownfield and infill sites within urban centers that are going vacant? These sites feed off existing services, roads and transit and leave rural land untouched.
Projects like NewHolly and the proposed High Point redevelopment in Seattle are a few local examples, and so is the successful Poulsbo Place, constructed near the town’s main shopping street. Rather than creating whole new towns all at once in the urban fringes, made up to look like they developed over time, we should be infilling within our existing urban infrastructure.
Saving land and resources is a key component of city development that we can no longer afford to ignore. Simply mimicking traditional town-making patterns from a time when our world was small enough to ignore sustainability won’t achieve this end. A rigid universal grid and code will not achieve this. It will be achieved by a flexible pattern, geared to recognizing the ability of natural characteristics to establish a strong sense of place, to connect to each region’s role in the ecosystem, and ultimately create more meaningful sustainable urban environments for ourselves and future generations.