Notes
Existing traffic operational analysis memorandum prepared by Zach Wieben of Concord Engineering for the Seattle-Tacoma International Airport (Sea-Tac Airport) Sustainable Airport Master Plan (SAMP) Near-Term Projects (NTPs) Environmental Review, Affected Environment chapter. Submitted to Steve Rybolt and Nic Longo at Port of Seattle, copied to Sarah Potter at Landrum and Brown, dated September 9, 2024. Analyzes 108 intersections (63 signalized, 41 stop-controlled, 4 uncontrolled) plus SR 518 and I-5 freeway ramps and segments at WSDOT request. Study area established per WSDOT Design Manual Chapter 320 Traffic Impact Analysis procedures; analysis conducted for weekday PM peak hour (4 p.m. to 6 p.m., Tuesday–Wednesday–Thursday). Attachments include Turning Movement Count Graphics, Synchro LOS Reports, SimTraffic Queues and Travel Times, HCS LOS Reports, and Approved Methods and Assumptions Documents.