Muck Valley Afterbay, located in Lassen County, California, is a privately owned hydroelectric facility that was completed in 1990. Designed by CH2M Hill, this earth dam structure stands at a height of 15 feet and has a hydraulic height of 13 feet. With a capacity to store 420 acre-feet of water, this afterbay is primarily used for hydroelectric purposes and is regulated by the Federal Energy Regulatory Commission.

Situated on the Pit River, the Muck Valley Afterbay spans a length of 6200 feet and has a spillway width of 200 feet for uncontrolled water release. Despite being classified as having a low hazard potential, it undergoes regular inspections by state agencies to ensure its safety and compliance with regulations. With a moderate risk assessment rating of 3, there is a focus on risk management measures to mitigate potential threats and safeguard the surrounding community in Pitville.

Overall, the Muck Valley Afterbay serves as a vital component of the region's water resource infrastructure, providing renewable energy through hydroelectric generation while maintaining a low hazard potential. Its strategic location, efficient design, and adherence to regulatory standards make it a key player in sustainable water resource management and climate-conscious energy production efforts in California.