The Federal Energy Regulatory Commission on Sept. 6 granted an April 2013 application from Baker County, Oregon, for a license to construct and operate the proposed Mason Dam Hydroelectric Project.
The project’s authorized capacity being licensed is 3.4 MW. The project will be located at the U.S. Department of the Interior, Bureau of Reclamation’s Mason Dam on the Powder River near Baker City in Baker County, Oregon.
The 173-foot-tall, 895-foot-long Mason Dam impounds the 2,235-surface-acre Phillips Reservoir, also known as Phillips Lake. Mason Dam was built on the Powder River by Reclamation to provide irrigation, water delivery, and flood control. Baker Valley Irrigation District provides for the day-to-day operation and maintenance of Mason Dam and controls flow releases at Mason Dam to the Powder River under an agreement with Reclamation.
The Mason Dam Project will use Reclamation’s existing reservoir outlet works, which will require modification of the discharge conduit to include a bifurcation to a new 105-foot-long, 72-inch-diameter penstock. The penstock will deliver flows to a new 40- foot by 28-foot powerhouse that will house a single 3.4-MW horizontal shaft Francis-type turbine-generator unit. The project will also require modification of the existing stilling basin to incorporate the project’s tailrace, and the construction of a new 0.8-mile-long, 12.47-kV overhead transmission line along Black Mountain Road to a new substation located within Idaho Power’s existing 138-kV transmission line right-of-way.
The project will be operated in a run-of-release mode, using flows that are released by Reclamation and/or Baker Valley for irrigation, flood control, or other purposes.