2019-10-22
This draft document, updated October 2019, summarizes an obstruction removal study conducted near Seattle-Tacoma International Airport, identifying 174 trees that penetrate or are predicted to penetrate FAA-required airspace surfaces. The trees are distributed across multiple property owners, with WSDOT holding the largest share (102), followed by Highline School District (26), private owners (19), SeaTac (21), and the Port (6). The study, which involved LIDAR scanning, FAA-approved analysis, and field verification, classifies the obstructions as topped, existing, or potential future penetrations, with conifers making up the vast majority of affected trees.