First AME Housing Corporation is redeveloping a site located in central Seattle, Washington. The project involves the demolition of the existing buildings on site and the construction of two new multi-family residential structures. Terraphase provided geotechnical engineering support for Phases I and II of the construction, which consists of seven- and six-story residential buildings with associated basement parking levels, respectively.

Scope of Services

Terraphase provided geotechnical engineering evaluations for each phase of the project. Our recommendations were instrumental in the design of the building foundations, temporary shoring, stormwater management systems, and other site development. After submitting the initial geotechnical reports for each phase, we continued to support the design process by reviewing temporary soldier pile shoring systems, preparing required plan review letters, and assisting with the design of modular block retaining walls.

During construction, Terraphase remained actively involved by performing observation and testing services. This included monitoring the installation of soldier piles, evaluating subgrade conditions for bearing capacity, testing backfill around foundations, and delivering Certified Erosion & Sediment Control Lead (CESCL) services for both phases of the project.

Notable Accomplishments

• Provided geotechnical evaluations for foundation, shoring, and stormwater system design
• Supplied required geotechnical plan review letters
• Performed construction-phase monitoring and subgrade evaluation
• Conducted backfill testing and CESCL services across both project phases