On June 2, 2014 the Tukwila City Council adopted a Southcenter Subarea Plan along with a new Southcenter Design Manual and Zoning District. These will implement the community’s vision for a high density, pedestrian oriented development served by high capacity transit in the area bounded by I-405 to the north, I-5 to the west, Tukwila city limits to the east, and approximately South 180th St. to the south.
During 2013 staff prepared a Supplemental Environmental Impact Statement (SEIS) to analyze the impacts of buildout of the Southcenter area as envisioned under the Plan. We took advantage of a relatively new SEPA process set forth in RCW 43.21C.420 that allows the City to comprehensively consider area-wide, cumulative environmental impacts of the Southcenter Plan project and appropriate mitigation over an extended time horizon, rather than evaluating impacts and mitigation on a project-by-project basis. Future project-specific development proposals that are consistent with the subarea plan, development regulations and SEIS will not require individual SEPA review and cannot be challenged administratively or judicially pursuant to SEPA. As such, the nonproject SEIS provides certainty and predictability for urban development proposals, by streamlining the environmental review process within the subarea and encouraging the goals of SEPA and the State’s Growth Management Act.