SEPA: Why It Matters

You may remember the federal review process from 2024—you may have even signed onto our letter! That was NEPA (the National Environmental Policy Act), led by the FAA, where we sent the letter. 

Now, we’re entering a similar process at the state level: SEPA, the State Environmental Policy Act, led by the Port of Seattle, who released the SAMP Draft SEPA EIS on May 22. This is a review of the cumulative community consequences of a major airport expansion. It covers issues that directly affect communities, including housing pressure, public health, air quality, noise, land use and zoning, roadway impacts, and cumulative impacts. It also reviews the broader consequences of an airport expansion program that will shape surrounding neighborhoods for years to come.

SEPA is different because it requires decision-makers to study how a project could affect and possibly harm:

  • The natural environment: air, water, trees, wildlife, and noise

  • The built environment: homes, traffic, public services, and community health

The Seattle Space Needle in the background surrounded by buildings and trees.

Why this moment matters

Right now, the SEPA process is the strongest way to secure meaningful protections for our community!

In 2024, thousands of you spoke up during the NEPA process.

Now we need to build on that momentum.

What’s happening now

The Port of Seattle is leading the SEPA review process. (Yes, they are both proposing the project AND signing off on its environmental review.)

SEPA requires agencies to study possible cumulative harm before they approve a project. It also allows agencies to add conditions, require protections, change a project, or choose a less harmful option.

Take Action! How you can help

1) Comment. Your voice can help shape the outcome.

  • The public comment period is open from May 22 to August 20, 2026, at 4 PM PDT.

  • Comment directly at the SAMP portal (use the template below to help guide what to include in a comment)

  • Share your story with us! (It doesn’t need to be in English.)

  • Need help writing? Try these question prompts to personalize your comments.

2) Ask family, neighbors, or coworkers to submit their own comments, in any language they are most comfortable using.

3) Attend SEPA-related meetings or the Port’s SEPA open houses and give oral comments or testimony.

4) Support community organizing.

  • Sign up for email updates from us so you know when new actions or deadlines come up.

  • Help share information about SEPA and airport impacts with your neighbors, school, or local organizations.

  • Volunteer to help with outreach, translation, interpretation, or event support.

5) Contact local elected officials and Port commissioners to ask for stronger protections from noise, pollution, and other cumulative impacts. Even better, form a group and go together!

People who live near SeaTac airport already face many combined impacts. These can include aircraft noise, air pollution, truck traffic, heat, tree loss, housing pressure, and stress on children, elders, workers, and families.

A strong comment can be short. We invite community members to share personal experiences about how this issue affects health, home, family, and daily life. We’re focusing on real stories that help decision-makers understand the human impact behind the data.

The most important thing is to explain how airport-related impacts affect your everyday life, your family, your school, your workplace, or your neighborhood.

Question Prompts

  • Where do you live, work, study, worship, or spend time?

  • How close are you to the airport, a flight path, a major road, a truck route, or a warehouse area?

  • What do you notice in daily life? For example: noise, bad air, asthma, sleep loss, stress, traffic, heat, fewer trees, or unsafe walking routes.

  • Who is affected? For example: children, elders, workers, people with asthma, people with disabilities, renters, small businesses, or people who speak languages other than English.

  • What protection would help? For example: air filtration, sound insulation, tree protection, cooling projects, safer streets, anti-displacement funds, public health monitoring, or clear reporting.

  • What do you want the Port to explain publicly?

Public Comment Template

Subject: Public Comment on the Port of Seattle/SeaTac Airport SAMP SEPA Review

My name is [YOUR NAME]. I live, work, study, worship, or spend time in [CITY OR NEIGHBORHOOD].

I am writing about the SEPA review for the Port of Seattle/SeaTac Airport SAMP.

Please fully study how this project will affect airport-impacted communities. Many people in our neighborhoods already live with aircraft noise, air pollution, truck traffic, heat, tree loss, and housing pressure. These impacts add up.

I am especially concerned about [CHOOSE ONE OR MORE: air pollution, ultrafine particles, noise, sleep, children’s health, asthma, traffic, truck traffic, tree loss, heat, housing displacement, small businesses, access to jobs, public accountability].

In my life or community, this issue matters because [ADD 1 TO 3 SENTENCES ABOUT YOUR EXPERIENCE].

I ask the Port to:

  • Study cumulative impacts from the airport, roads, warehouses, freight, and other nearby projects.

  • Use community data, public health data, and lived experience when studying harm.

  • Compare less harmful options and stronger protections.

  • Require clear mitigation, monitoring, translation, and public reporting.

  • Show the public how community comments changed the final decision.

Please do not approve this project without strong protections for the people who already carry the heaviest environmental and health burdens.

Thank you,

[NAME], [NEIGHBORHOOD/ZIP]

Common Questions About SEPA and NEPA

  • NEPA is a federal environmental law that requires agencies to study how major projects may affect people and the environment. For airport projects like SAMP, the Federal Aviation Administration (FAA) is the lead agency. The FAA runs the NEPA review and decides whether a project will have significant environmental impacts.

    The FAA completed an Environmental Assessment for the SAMP in 2025. After that review, the FAA issued a “Finding of No Significant Impact” (FONSI), which means they decided the project would not cause significant environmental harm, as long as certain conditions are met.

  • SEPA is a Washington State law. For SAMP and other Port projects, the Port of Seattle is the lead agency for SEPA.  SEPA requires the Port to study possible harms to both the natural environment (air, water, trees, animals, noise) and the built environment (homes, traffic, public services, and community health) before making decisions.

  • SEPA is different because, unlike NEPA, it requires decision-makers to study how a project could affect and possibly harm:

    • The natural environment: air, water, trees, wildlife, and noise

    • The built environment: homes, traffic, public services, and community health

  • SEPA is the chance for Washington State and the Port to go further than NEPA: to look closely at local health, housing, traffic, and economic impacts in airport‑impacted neighborhoods, and to add clear protections, monitoring, and accountability so that future airport growth does not increase harm where people already carry the heaviest burdens.

    SEPA lets the Port, as lead agency, condition, change, or even deny a project based on the environmental information. The Port can require extra protections, monitoring, or changes to design to reduce harm in nearby communities.

    SEPA can—and should—look at how many different pollution and impact sources (airports, highways, rail lines, and warehouses) stack up in the same neighborhoods. It can then require local, community‑driven mitigation to address those combined harms, rather than looking at each project in isolation.