HWA provided geotechnical engineering services in support of a new stormwater and CSO conveyance system along the Everett Waterfront. HWA and the design team developed an innovative solution that included the construction of a utility bridge to carry a CSO, water main and storm drain line from the top of the slope to the waterfront. This project was the winner of the 2023 AIA Seattle Honor Awards - Award of Merit and the 2023 American Architecture Award for Bridges and Infrastructure.

The USPS Pedestrian Bridge required replacement during site improvements, with a fast-tracked schedule and tight budget. HWA reviewed subsurface data and provided design recommendations. HWA determined shallow foundations on dense glacial till were suitable, advising over-excavation at the north foundation and direct bearing at the south. HWA’s report addressed seismic parameters, earthwork, groundwater, and shoring, confirming favorable conditions with proper preparation and monitoring.

HWA provided geotechnical support for the 33rd Avenue Pedestrian Bridge in Seattle, Washington. HWA’s tasks included site reconnaissance, field explorations, installation of groundwater monitoring wells, laboratory testing, settlement analyses, and design and construction recommendations for the replacement bridges and associated retaining structures for rehabilitation. HWA coordinated with community members, Seattle Parks and Recreation, and BNSF Railway Company.