Energy Northwest’s first electric power project (Packwood Lake Hydroelectric Project) – started in 1962, and operation began in 1964. Located five miles east of Packwood, Wa, in the Gifford Pinchot National Forest, it has the capacity to produce 27.5 megawatts of electricity.

The project was conceived and designed to be operated with minimal impact on the lake and surrounding area. The power plant structures are limited to a small diversion and intake structure a short distance downstream from the outlet of Packwood Lake. A five-mile underground pipeline carries the water down the mountainside to a powerhouse. The 1,800-foot drop in elevation creates 780 pounds per square inch of pressure at the generator turbine, which produces the electricity.

We pay roughly 14% of the cost of the project, and in return it recieves 14% of the output.

Packwood Lake Hydro Diagram

Packwood Hydroelectric Project Stats


  • The Packwood Hydro Project is located 5 miles East of Packwood, WA


  • The powerhouse has a 27.5 MW capability
  • A diversion dam on Lake Creek 424 ft downstream of the outlet from Packwood Lake feeds water to the powerhouse through a system of concrete pipes and tunnels. The 1,800 ft drop creates 780 pounds per square inch of pressure by the time the water reaches the turbine.

Power Production Capability

  • Installed capacity of 27.5 megawatts (MW)

Lewis County PUD’s Share

  • We have a 14% off-taker agreement and receives roughly 3.85 aMW.


Construction Highlights

  • Construction Permits Issued July 1960
  • 50-year Operating License Issued July 1960
  • Construction Started Spring 1962
  • Project Testing and Initial Operation June 1964
  • Re-licensing Application Submitted February 2008
  • Notice of Authorization for March 2010

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