This is More Important: Setting the Density of Urban Centers in King County
Citytank and other Seattle blogs have lit up recently with debates over the densities at the new Link Light Rail station areas, such as in the Roosevelt neighborhood. But there’s a more important fight happening, and few people are paying attention.
For the first time in two decades, the Growth Management Planning Council of King County is set to make the first major update of the “countywide planning policies” on June 27. These policies establish the framework for all local land use and transportation plans—serving as the foundation for how we approach everything from climate change to affordable housing.
At the intersection of the entire update are the minimum standards for “urban centers.”
With 724,000 people moving to King County in the next 30 years—a 37% increase—we need to design our cities to function much more efficiently. This means encouraging compact neighborhoods that support transit, bikes, and pedestrians and reduce the need for car trips. The result will be more vibrant and livable cities with thriving small businesses, active streetscapes, and more housing options.
Unfortunately, the staff recommendation on density for urban centers is woefully inadequate—the recommendation maintains the out-dated density of only 15 residential units per gross acre. That level of density is in the range of a typical townhouse development. Why would we set such a low target for neighborhoods like Northgate, Overlake, or South Center?
In 2009, Futurewise, GGLO, and Transportation Choices Coalition published the report Transit-Oriented Communities: A Blueprint for Washington State. Based on a synthesis of the best available information, the report proposed a set of recommendations for creating diverse, equitable communities in which people can meet most of their daily needs with relying on a personal automobile. And key among these was a minimum threshold for zoned capacity of 30 residential units per gross acre.
Numerous studies have documented that as densities rise from typical suburban densities towards 30 units per gross acre, the result is a significant reduction in vehicle-miles-traveled and the associated greenhouse gas emissions. One study showed that 50 units per residential acre is an approximate tipping point at which transit or walking surpass car trips (see adjacent graph, and note that a conversion from “residential acres” to gross acres would reduce the density of the mode crossover by 25% or so).
This density is not Mumbai, Beijing, or Tokyo. Three to five story buildings can easily meet this standard. Urban center neighborhoods exceeding 30 residential units per gross acre can be composed of a diverse and functional mix of single-family homes, townhouses, and taller buildings.
Furthermore, these standards would not apply to all neighborhoods in the county—just to those designated urban centers that have already signed up to accommodate future residential and job growth.
While the debates at Roosevelt and the other Light Rail station areas are important, the update to the King County countywide planning policies presents a unique opportunity to have a much bigger impact. For the next week, let’s focus on the countywide planning policies and set minimum standards for functioning cities to handle the coming 724,000 people.
After all, given it took two decades for the first major update, this could easily be the last update for the next two decades. We cannot afford to miss our chance.