A
Publish and Present
Ellis Beckwith, P.E.
Associate
KPFF Consulting Engineers
Seattle, Washington
Scott Adamek, P.E., LG
Senior Environmental Engineer
Floyd|Snider
Laynl Wachter
Environmental Engineer
Floyd|Snider
Treating industrial stormwater at port container terminals requires a multidisciplinary approach and site-specific solutions, and the Terminal 18 (T18) Stormwater Improvements Project exemplifies this. T18 is located within the Harbor Island Superfund site in Seattle, Washington, and is one of the largest container terminals in the Pacific Northwest. Washington has one of the strictest permit requirements in the county for common stormwater contaminants of copper and zinc. Subsequent to a third-party lawsuit, the terminal operator and the state entered into an agreement in 2015 for the terminal operator to implement stormwater treatment to meet industrial permit discharge requirements. The agreement required stormwater treatment be constructed by 2020 in three phases. This required strategically implemented best management practices, well-informed treatment selection and an alternatives analysis balanced to meet regulatory and site operator requirements. Following construction, the active treatment systems installed have consistently met benchmarks while some passive treatment systems installed have produced mixed results, requiring focused adaptive management through trouble shooting and modified operations and maintenance schedules.