Pearl Street Drainage and Wastewater Improvements

Facet conducted options analysis, hydraulic and hydrologic modeling, and conceptual level engineering design to alleviate sewer backups and surface flooding in the Pearl Street basin. Early tasks involved collection and review of available data and identification of data gaps. The existing EPA Stormwater Management Model was calibrated and updated for the various options considered. The team organized a workshop with SPU to facilitate development of options. Options discussed included, but were not limited to, GSI, stormwater separation, stormwater diversion, detention, I&I reduction, backflow prevention/pumps, and increased pipe conveyance capacity. Preliminary engineering design including exhibits and cost estimates on the selected options are ongoing. The cost estimate for the options will be based on the SPU Stage Gate 2 cost estimating guidelines. This project involved coordination with multiple stakeholders such as SDOT, Parks Department, Seattle Public Schools, WSDOT, private utilities, and the public.

Location:

Seattle, WA

Client:

Seattle Public Utilities