Pit No. 1 Forebay, located in Fall River Mills, California, is a privately owned hydroelectric dam completed in 1947 with a primary purpose of generating hydroelectric power. The dam stands at 46.5 feet in height with a hydraulic height of 35 feet and a structural height of 44 feet. It has a capacity of storing 3,212 acre-feet of water, with a normal storage level of 614 acre-feet and a maximum discharge of 13,000 cubic feet per second.

The dam spans 586 feet in length and has a surface area of 222 acres, serving a drainage area of 725 acres. It features a controlled spillway with a width of 45 feet and is equipped with two Tainter (radial) outlet gates. The dam's hazard potential is classified as high, and it has a very high risk assessment rating. While the condition assessment of the dam is not available, it is regulated, permitted, inspected, and enforced by various state and federal agencies, including the Federal Energy Regulatory Commission.

Despite its age, Pit No. 1 Forebay remains a crucial component of California's water resource infrastructure, contributing to the generation of clean energy and water management in the region. Its strategic location on the Fall River underscores its importance in the local ecosystem and highlights the need for ongoing monitoring and maintenance to ensure its continued safe operation and resilience in the face of changing climate conditions.