TagPort Of Seattle(2604)

The cities of SeaTac, Burien, and Des Moines jointly wrote to the Port of Seattle on May 18, 2026, requesting a 90-day public comment period for the Sustainable Airport Master Plan (SAMP) Draft Environmental Impact Statement. The cities cited the document's technical complexity, overlapping regional demands including 2026 FIFA World Cup preparations, summer scheduling constraints, and unresolved concerns from the prior federal environmental review as reasons more time is needed. The letter was signed by the SEPA Responsible Officials from all three cities and emphasizes that airport-related impacts on noise, air quality, transportation, and public health directly affect their communities.

This section of the May 2026 Draft Environmental Impact Statement for Seattle-Tacoma International Airport examines how the airport's near-term construction projects may combine with other past, present, and planned developments to create cumulative environmental effects. The analysis covers 58 projects in the surrounding area—including housing, road improvements, and airport expansions—completed or expected between 2017 and 2032, within a study area defined by the airport grounds, the 65 DNL noise contour, and the surface transportation zone. Long-term airport expansion proposals beyond 2032 are excluded from the analysis because they lack sufficient detail and funding approval to allow meaningful review.

The Port of Seattle has released a Draft Environmental Impact Statement (EIS) under Washington State's environmental review law for 31 near-term construction projects at Seattle-Tacoma International Airport (SEA). The projects, which include a new 19-gate terminal and an elevated busway system, are designed to handle up to 56 million passengers by 2032. While a prior federal review found no significant environmental impacts requiring mitigation except for surface transportation, this state-level review evaluates two action alternatives alongside a no-action scenario.

This report analyzes existing traffic conditions around Seattle-Tacoma International Airport as part of the Sustainable Airport Master Plan (SAMP) Near-Term Projects Environmental Review. It examines 108 intersections—including signalized, stop-controlled, and uncontrolled locations—along key travel routes connecting the airport to surrounding communities, focusing on weekday PM peak hour traffic volumes. The study also includes freeway analysis of SR 518 and I-5 ramps and segments at the request of WSDOT.