Projects » Downtown Seattle Conventional Excavation

Projects » Downtown Seattle Conventional Excavation

Client: GLY Construction

City: Seattle

Size: $7,100,000

Depth: 30 feet average below grade


Total Soil: 207,000 Cubic Yards

    Impacted Soil:  150,000 tons

    Structural Excvation:  1800 Cubic Yards

    Structural Backfill:  8,500 tons



Teaming with partner GLY Construction, NWC performed site work in preparation for a new downtown building.  This major excavation & utilities operation included the demolition, TESC, site storm, sewer and water utilities, mass excavation of parking garages, and structural excavation for footings and foundations and ROW improvements for four new buildings over two complete city blocks.  Environmental challenges arose but were dealt with in classifying over 150,000 tons of impacted soils, finding and delivering for disposal at appropriate dumpsites. Mid-project, a significant water stream began entering through the shoring wall. This was quickly investigated, sourced, isolated and stopped to ensure the project continued on time and on budget.  The bulk of the project was completed in just a little over four months, through day and night excavation, load out and haul out.   A project highlight was the creation of a new alley grade through overnight backfilling with 8,500 tons of imported material.