The American Council of Engineering Companies (ACEC) of Washington’s annual Engineering Excellence Awards were announced last Friday, January 18, 2019. Golder received Gold and Silver awards for its work.
Golder received a Best-in-State Gold Award for the I-90 Snowshed to Keechelus Dam Phase 1C project. As part of the design-build team led by Atkinson Construction and Jacobs Engineering, Golder’s challenge was to support the design and construction of rock cut stabilization measures for the Washington State Department of Transportation’s twin bridges over six avalanche chutes along I-90 at Snoqualmie Pass. The success of the project relied in part on safe but economical stabilization of rock cuts required to facilitate the construction of the bridge. By accounting for specific, unique site conditions, Golder optimized the cut inclination by balancing three objectives: reducing reinforcement, avoiding excessive cuts, and enhancing constructability. Potential rockfalls were also modeled using a rock fall incident during construction as a tool to calibrate and mitigate potential impacts of falling rock on the bridge piers. The slope has been monitored daily using instrumented dowels since 2014 and is performing as expected.
Golder also took home a Best-in-State Silver Award for the Blackbird Creek In-Channel Stabilization Design project. The project used geomorphic design principles to remediate historical-contaminated mine sediments in a targeted nine-mile reach of Blackbird Creek, a remote site outside of Salmon, Idaho. Golder designed an integrated instream stabilization system that mitigated the remobilization of contaminated sediments at depth through targeted removals, bank armoring, and an extensive integrated system of 80 grade-control structures and 61 bendway weirs that modified the historical stream morphology from a deeply incised and highly erosion and scour prone regime, to a broad and shallow and low-erosion regime. The project established a stable channel and floodplain where vegetation is taking hold and has dramatically increased the ecological rate of recovery in Blackbird Creek. Performance monitoring from 2010-2018 secured regulatory agency endorsement and approvals for the project.
The Graham Contracting and Stantec Consulting Services design-build team received a Best-in-State Gold Award for the US 12 Wildcat Creek Bridge Replacement project, which Golder was the lead geotechnical consultant. The 80-year old dilapidated bridge was replaced by an arch culvert bridge using reinforced soil retaining walls. Golder provided engineering input to the reinforced soil retaining wall design and arch culvert foundation design as well as support during construction. The bridge was constructed in a 17-day window.
