EXH1264050780

5808 Lake Washington Blvd. N.E., Suite 200 Kirkland, Washington 98033-7350 July 2001 556-2912-001 (28) AR 050780 Assessment of the Existing and Future Hydrologic Divide of Miller, Walker. and Des Moines Creeks after Construction of Master Plan Update Projects at Seattle-Tacoma International Airport Master Plan Update (MPU) construction at Seattle-Tacoma International Airport (STIA) will require earth movement, new pavement, and construction of new drainage systems. These changes potentially modify the location and area of land that drains to Des Moines, Miller, and Walker Creeks. The Governor's Certification requires that "the Port of Seattle will design and construct the third runway such that the project will not cause changes in the location of the hydrologic divide between Miller and Des Moines Creeks in a manner that alters the average instream flow of either creek." The following text, figures, and tables demonstrate the Port's compliance with this requirement of the Certification. Note that Walker Creek. a tributary of Miller Creek, has been separated and assessed individually for compliance with the Certification. Figures Ala and Alb show the delineation of drainage basins in 1994 (the "existing condition") and 2006 (the "future condition") after MPU completion. The area depicted on these figures shows what has been called the "STIA" area in the Comprehensive Stormwater Management Plan (SMP). The STIA area represents all of the drainage basins that include MPU projects. There are no MPU project areas outside of the STIA area; however, not all of the basins shown in the STIA area have MPU projects,…

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Call to order – Roll Call – Quorum Established – Land Acknowledgement We would like to acknowledge that our Agency operates in four present-day counties, which are the traditional lands of the Coast Salish people, past and present. This acknowledgement does not take the place of authentic relationships with indigenous communities in our jurisdiction and [...]