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Gray, Green, and Blue: Seattle’s Northgate
Suburbs have long been perceived as offering a healthier lifestyle than cities. While escape from infectious diseases in overcrowded cities used to be a prime concern, today’s public health officials are much more worried about chronic diseases associated with sedentary lifestyles and the environmental and public health impacts related to lifestyles dependent on driving.
Obesity and fatalities from car accidents correlate strongly with suburban populations. Rising rates of suburban poverty and an aging population are additional concerns factoring into the retrofitting of auto-dependent areas with single-use zoning into more walkable, diverse, compact, and connected communities. Design decisions at a variety of scales play a crucial role in these transformations. Perhaps nowhere is this more evident than in the ongoing retrofit of the Northgate neighborhood into Seattle’s first transit-oriented development (TOD.)
Northgate is home to one of the country’s oldest shopping malls. It’s bisected by an interstate and crossed by the headwaters of Thornton Creek, a keystone salmon stream that was culverted into a 60-inch pipe below the mall’s parking lot. Its arterial roads are lined with scattered strip malls and residential neighborhoods whose diverse population is housed in relatively small single-family homes on relatively large blocks unconducive to walking.
In accordance with the Washington State Growth Management Act of 1990, Northgate was designated one of six urban centers in Seattle targeted for significant growth. This provided the impetus to redevelop and re-green its unhealthy parking lot–dominated and auto-dependent landscape. Equally important was reducing development pressure on Seattle’s exurban periphery, with the associated health benefits of reducing overall vehicle miles traveled, emissions, and runoff.
Well-designed TODs with adequately sized public transit systems can reduce household driving 40 percent, and are projected to save as much as 64 percent if they meet LEED for Neighborhood Development (LEED-ND) standards. But achieving such targets is especially challenging when redevelopment will necessarily be incremental. Northgate’s light rail station is expected to open in 2021 and stimulate significant private investment in walkable, mixed-use redevelopment. What steps are being taken to prepare the ground? The city has revamped its zoning authorization to incentivize densification and the provision of more affordable housing—important tools to increase access to the health benefits of TOD. Simultaneously, urban designers have established a civic infrastructure of new parks, a new library and community center, shared underground parking facilities, and proposed new bike and walking trails to anchor redevelopment and connect with the existing neighborhoods.
Architects have introduced new models of compact urban living to the area, including Thornton Place, a LEED-ND Silver mixed-use residential project. Bert Gregory, FAIA, CEO of Mithūn, has worked at all of these scales through his firm’s work on Thornton Place, the new Northgate Park, and the 2009 Northgate Urban Framework Plan. “Helping the community envision the path forward and form partnerships has been crucial to the project’s success,” Gregory says.
This is particularly true of the parking-lot-to-parkland swaps that were catalytic to redevelopment. To get permission to expand, the mall sold 13 acres of its southern parking lot, including the portion over the culverted Thornton Creek. The west half, which currently serves as a bus transit station, is planned to be densely redeveloped when the light rail opens. The east half has been redeveloped: Thornton Place to the north, Aljoya Thornton Place (senior housing) to the south, and the dramatic re-greening of Thornton Creek at the center.
On the site of the former parking lot, a popular public boardwalk snakes alongside the lush engineered green infrastructure that treats the runoff of over 680 acres before feeding the creek. Similarly, a county-owned park-and-ride north of the mall was swapped for space in the new transit station parking garage under Thornton Place (where it shares parking with a movie theater). The former park-and-ride lot has been re-greened into Northgate Park, triggering several nearby redevelopment proposals for urban housing facing the new park. The neighborhood received additional public space when a vacant Goodyear Tire store east of the mall was redeveloped into a library, community center, and park designed by Miller Hull. Plus, a new community garden has been established nearby.
Collectively, these varied parks are providing a much-enriched public realm, an essential component to making compact urban living attractive. They also provide health benefits by raising social capital, increasing physical activity, and providing access to healthy food while improving water quality and natural habitats for flora and fauna.
Neighborhood in transition
At the building scale, the design of Thornton Place both raises the standards for healthy urban housing for the neighborhood and successfully negotiates the challenge of pioneering placemaking in an area that is still evolving.
The LEED Silver buildings, which incorporate a district heat system, recycled 90 percent of construction waste. They meet the two street fronts in a manner that anticipates a more urban context in the future. Parking is underground and accommodates shared-use vehicles. The development mixes incomes with subsidized and market-rate dwelling units, diversifies the area’s housing choices, and mixes uses. With over 80 dwelling units per acre, the development both introduces significant density to the area and perforates it with compelling public places. Apartments wrap a mid-block plaza activated by the theater and ground-floor retail. Townhouses are accessed from an intimate mews, a step down along the oasis of Thornton Creek.
As is common in suburban retrofits, these distinctively urban pedestrian public spaces are internal to the block and shielded from the still-unwelcoming auto-oriented context. Nonetheless, Gregory points out, the range of pedestrian options and access to the transit center is already increasing the popularity of a walkable lifestyle. Twenty percent of area residents do not own cars, and purchase of public transportation passes has increased from 16 percent to nearly 80 percent since completion of Thornton Creek.
Today, Northgate is still very much a neighborhood in transition, moving from car-dependent and suburban to public transit–oriented and more urban. But it’s also making a transition from a wide, sweeping surface parking lot grayscape to a hybridized place where development and nature grow in tandem, a vital precondition for attracting and retaining residents to more carbon-efficient urban lifestyles. The long-term public health impacts of Northgate’s redevelopment and re-greening remain to be fully documented, but native birds and volunteer plants have already established themselves—always a good sign.
Ellen Dunham-Jones, AIA, is a professor of architecture and urban design at the Georgia Institute of Technology School of Architecture. She is also the author (with June Williamson) of Retrofitting Suburbia: Urban Design Solutions for Redesigning Suburbs (Wiley).
Mithūn’s Thornton Place in Northgate. All images courtesy of Mithun.
Aerial view of Thornton Place.
Aerial view of Thornton Place site, before project was completed.
Thornton Place’s natural water-treatment systems filter urban stormwater runoff drawn from 680 acres.
A site map of Northgate and Mithun’s Thornton Place.