Port Properties and Trees mapped

Properties, trees and the environment around the airport

As the icon indicates, this is a beta project, one of a series of visual representations on community impacts. This indicates Port-owned properties around the airport, most purchased with FAA grants. It also displays the status of trees that are subject to removal and/or replacement via the Flight Corridor Management Program and its Inventory

• The first layer shows the 46 properties owned by the Port around the airport.
• The second layer shows the 2,800+ trees inventoried by the Port according to the Land Stewardship Plan.

Red markers indicate that evaluation is incomplete. Green markers are complete. We are unsure as to the meaning of these, but it appears that green markers are subject for removal in the current cycle.

The next step will be to add historic tree removals over time on those properties.

Background

Over the decades, the Port of Seattle and WSDOT have, in tandem, literally re-shaped the airport communities.

• In 2003, WSDOT finalized the right of way for SR-509, which only now is being built out near the airport, and with significant impact to tree canopy and habit.
• In 2008, the Port of Seattle developed the fifteen acre Auburn Wetlands site, now a mitigation bank, to compensate for the environmental harms of building the Third Runway Project.
• In 2012, the City of Des Moines signed the current agreement authorizing the Des Moines Creek Business Park.
• In 2014 the Port of Seattle created a LiDAR survey of trees and other potential obstructions to aviation, supposedly at the behest of the FAA.
• In 2016, the Port of Seattle Commission formally approved the Flight Corridor Safety Program. As the name implies, the program is meant to remove any obstructions to safe passage by aircraft. The initial program proposed the removal of up to 3,000 trees. Over time, the program has been revised and scaled back several times. As of 2024, the number removals has been 975.
• In 2017 the Port of Seattle engaged Forterra to create an area tree canopy study called the Greener Cities Partnership.
• In 2018 the Port negotiated an agreement with Hillgrove Cemetery to allow removal of several old growth trees in exchange for a new gate and a permanent landscaping program.
• 2023, the Port began developing a Land Stewardship Plan, supposedly to better manage tree replacement. Unfortunately, the Port Commission decided that its rules would only apply on airport property; and that other Port properties would remain subject to the standards of munipalities.
• 2025 The Port has renamed the FCSP as the Flight Corridor Management Program and on August 20th published  a SEPA Flight Corridor Management Program Checklist which describes current management practices.

According to that document, there have been three phases of tree removal, including the current cycle:

We take that to mean 1,561 out of the original (prox.) 3,000, or over 50%.