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SeattleGeolocation: 47.8005, -122.3181
Terracon (formerly Zipper Zeman Associates, Inc.) has been serving clients in the greater Seattle area since 1998.
After operating in the greater Seattle area and Portland, Ore., since 1998, Zipper Zeman Associates, Inc. joined Terracon in 2005. These local offices officially became Terracon in 2009. The Seattle office provides multiple related service lines to clients at local, regional, and national levels.
In the Northwest, Terracon specializes in geotechnical engineering, environmental consulting, and construction materials engineering and testing services. Terracon's basic strength is our commitment to our local clients; we are proud of our commitment to the Northwest region. The senior engineering staff of Terracon's Washington offices offers more than 250 years of local experience.
21905 64th Ave. W., Suite 100
Mountlake Terrace, WA 98043
Phone: (425) 771 3304
Fax: (425) 771 3549
Services
Geotechnical
Environmental
Construction Materials
Facilities
Contacts
Key Projects
Kent/Auburn Conveyance System ImprovementsGeolocation: 47.548, -121.9836
This project consists of approximately 12,500 linear feet of gravity trunk sewer and 10,000 linear feet of sewer force main, and includes five railroad and highway trenchless crossings. Terracon completed pre-design geotechnical and environmental evaluations for several alignment alternatives. Following these evaluations we were asking to perform design phase geotechnical and environmental evaluations for the four preferred alignments that were selected during the pre-design phase.
North Twin BridgeGeolocation: 47.4018, -122.3243
Terracon was contracted to provide geotechnical services to assess site conditions at the North Twin Bridge in Des Moines, Wash. The bridge was built in 1950 and is about 230 feet long, spanning a steep sided ravine above McSorley Creek. During initial observations of the site, a void was discovered below the foundation of Bent 1. Terracon evaluated the existing foundation support conditions at Bent 1 and provided recommendations for methods for emergency foundation repair. Additionally, Terracon also provided options for seismic retrofit intended to upgrade the bridge to a performance…
South Shore SchoolGeolocation: 0, 0
Located in Southwest Seattle, the South Shore School is a new $40-million structure replacing the existing South Shore building. Though designed to meet the growing program needs, the structure still maintains its communal roots by remaining attached to the Rainier Beach Community Center and sharing a larger educational and community-use campus. Designed to symbolize community and inclusiveness, the new facility will provide a unique space for connection and unification of students while emphasizing personalized learning. Throughout the construction, Terracon had a full-time,…