Project Description


Olsson Industrial Electric, OS Engineering and Olsson Controls collaborated to modernize a station service electrical distribution system for the Dalles Dam. The Olsson team functioned as the prime contractor for the comprehensive upgrade of this 2100 MW hydroelectric power generation facility. Olsson completed the upgrade of the original 1950s control systems, wire distribution replacement for improved cable infrastructure quality and creation of internal redundancy through connecting a secondary power source. This electrical renovation resulted in improved turbine control, power generation system efficiency and system dependability and serviceability.

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  • Replaced protective relaying and breaker controls of 4160V station service system
  • Installed two 5000kVA station service transformers
  • Replaced main unit Isolated Phase Bus (IBP) 13.8kV CLR and vacuum switchgear
  • Retrofitted five 480V station service substations as well as MCC sections
  • Installed five new 500kVA transformers, 4160V switchgear, and switchgear sections
  • Retrofitted all 4160V switchgear sections
  • Designed, installed and tested preferred AC and redundant DC systems


  • Zero safety incidents during work in an energized power production facility 
  • U.S. Army Corps of Engineers “Outstanding” performance rating

Project Details

  • Location: Klickitat County, WA

  • Client: U.S. Army Corps of Engineers

  • Timeline: Sept. 2008 – Dec. 2013