Pier 70 – 20th Street Historic Corridor

Located within the National Register’s Union Iron Works Historic District, the Pier 70 - 20th Street Historic Corridor served as a major center for the West Coast shipbuilding company, Union Iron Works. Being abandoned and deteriorating over decades resulted in an urgency to save the six-building complex, which is considered to be the most intact 19th-century industrial complex west of the Mississippi. A major challenge for Langan’s geotechnical team was the foundation design as portions of the buildings are seaward of the historic shoreline. The foundation system, which included a combination of shallow footings into bedrock and micro-piles joined by grade beams, allowed new columns to be placed in architecturally desirable locations. In some areas, the new foundations are next to, or even span over, existing foundations. Over 100 micropiles were installed within the six buildings at the site.

2019 California Preservation Foundation, Design Award for Rehabilitation