Transportation

Tacoma Trestle Track & Signal The Tacoma Trestle Track and Signal project is a collaborative effort between Sound Transit, WSDOT, and the City of Tacoma to build a new bridge supporting double tracks and a passenger platform. The project consisted of the demolition of an existing single-track railroad trestle and the construction

South Boeing Access Road over Airport Way Seismic Retrofit The South Boeing Access Road over Airport Way project will provide structural analysis and seismic retrofit for the existing concrete structure. The work performed by 1 Alliance consisted of performing limited topographic mapping to provide a preliminary base map for project improvements. 1

SR 520 West Approach Bridge North This West Approach Bridge North project replaced the existing 1.2-mile long bridge structure that was seismically vulnerable to a catastrophic earthquake and extended SR 520’s three westbound lanes from the floating bridge to the Montlake area in Seattle. 1 Alliance provided design-build surveying services, including control

100th Avenue NE Corridor Improvements As one of the busiest arterials in the City of Kirkland, the project designed improvements on 100th Avenue Northeast Corridor between Northeast 132nd and Northeast 145th streets to address issues on this busy corridor such as lack of sidewalks and bicycle lanes, excessive congestion, and inefficient intersections.

I-5/116th Street NE Interchange Improvements Phase 3 of the interchange improvements project reconstructed the existing three-lane bridge over I-5 to a six-lane bridge and connected the widening of 116th east and west of the interstate. 1 Alliance provided structural surveying of the bridge structure drilled shaft, bridge substructure, bridge superstructure, bridge approach

I-5 Portland Avenue to Port of Tacoma Road - Northbound HOV As part of the Tacoma/Pierce County HOV Program, the project widened northbound I-5 to provide room for one HOV lane to increase capacity and improve freeway access between Portland Avenue to Port of Tacoma Road. 1 Alliance performed roadway and structural

SR 167 Southbound HOT Lane The project widened SR 167 to add a lane in the southbound direction and constructed a new flyover ramp connecting the High Occupancy Toll (HOT) Lanes system to the carpool lanes on I-405, providing an extension of the HOV/HOT lane for approximately eight (8) miles. 1 Alliance

SR 520 West Connection Bridge As part of the SR 520 Floating Bridge Replacement and HOV program, 1 Alliance provided surveying services for the 1,330-foot long West Connection Bridge that connected the new floating bridge to the existing SR 520 roadway. The 1 Alliance team provided structure and roadway surveying tasks that