Sustainable Airport Master Plan (SAMP)

Environmental Review for Near-Term Projects

Photo courtesy of the Port of Seattle

Update as of August 20, 2026

The 90-day comment period for the State Environmental Policy Act (SEPA) Draft Environmental Impact Statement (DEIS) for the Sustainable Airport Master Plan (SAMP) Near-Term Projects (NTPs) is now closed. The Port of Seattle is currently reviewing the comments received through the comment period. The response to comments will be published as part of the Final Environmental Impact Statement.

If you would like to stay updated on next steps and be notified when the final document is released, sign up for our email newsletter by selecting the Sustainable Airport Master Plan notifications box underneath the “Environment and Sustainability News” section at: https://subscribe.portseattle.org/publications.

What is the Master Plan?

To meet our region’s future needs and support a great traveler experience, the Port of Seattle has proposed a plan to guide future development for the Seattle-Tacoma International Airport (SEA). The planned projects will not only make SEA more efficient but will include benefits for people using and working at the airport, as well as improve transportation in and around the facility.

As part of the master plan, the Port of Seattle identified 31 Near-Term Projects (NTPs) to improve airport operations, safety, and access in the coming years.

What are the NTPs?

Key projects in the master plan include:

• Building a second terminal with 19 gates to reduce crowding, ensure more on-time flights, and generate more jobs
• Airfield updates to improve safety and efficiency
• Increased fuel storage
• Off-site air cargo facilities
• New roads to connect existing and new facilities

All of these projects are being evaluated together to understand their potential environmental effects and how to address them.