The Federal Energy Regulatory Commission has issued a new (subsequent) operating license for the 223.788-MW Middle Fork American River Hydroelectric Project in California.
The project is owned by Placer County Water Agency. The original operating license was issued in March 1963 and expired in February 2013. Since then, the project has operated under an annual license pending the disposition of its application for a new license. The city filed the application for a subsequent license in February 2011.
The Middle Fork Project is located in Placer and El Dorado counties and on the Middle Fork of the American River, Rubicon River, Duncan Creek and North and South Fork Long Canyon creeks. It includes seven dams – Duncan Creek diversion dam, French Meadows dam, Hell Hole dam, North Fork Long Canyon Creek diversion dam, South Fork Long Canyon Creek diversion dam, Middle Fork interbay dam and Ralston afterbay dam – and five powerhouses: French Meadows, Hell Hole, Middle Fork, Ralston and Oxbow.
The 15.3-MW French Meadows powerhouse contains a single Francis turbine-generator unit. Discharged water is supplied to the 725-kW Hell Hole powerhouse. From there water flows to the 61.2-MW Middle Fork powerhouse, with two Pelton turbine-generator units. The 79.2-MW Ralston powerhouse contains a Pelton turbine-generator unit. Finally, the 6.128-MW Oxbow powerhouse contains a Francis turbine-generator unit. The overall project is operated in a seasonal store and release mode and has an average annual generation of about 1,039,078 MWh.
FERC staff found that, as licensed with staff measures, project power would cost $27.22/MWh in the first year of operation, less than the likely alternative cost of power.
FERC issued a 40-year license for the project, effective June 1, 2020.