The Dalles is a 22-unit powerhouse located on the Lower Columbia River upstream of Portland, Oregon.
It has a rated capacity of about 1,800 MW and accounts for about 7% of the total
hydroelectric power generated by the Corps of Engineers Columbia River Projects.
The project has been producing commercial power since 1957, and has been experiencing an
increasing number of failures with the 14 older generating units in the powerplant. These
failures stem from nearly 40 years of combined base load and peaking operation.
In an effort to remedy these equipment failure problems, a comprehensive study was
initiated in about 1993 to investigate potential solutions to the generator reliability
problems and to restore lost turbine efficiency. The study was completed in March
1995, and recommended rewinding many of the generators and replacement or refurbishment of
turbine blades and other equipment on many of the units. Work is currently underway to
rehabilitate the powerhouse.
