Tioga Lake Main is a privately owned dam located in Mono County, California, near Lee Vining. Built in 1928, this rockfill dam stands at 27 feet high and spans 270 feet in length, providing hydroelectric power and recreational opportunities in the area. With a storage capacity of 1254 acre-feet and a surface area of 73 acres, Tioga Lake Main serves as a vital water resource in the region, fed by Glacier Creek.

Managed by the Federal Energy Regulatory Commission, Tioga Lake Main has a high hazard potential and is regulated and inspected by both state and federal agencies. Despite its age, the dam's condition assessment is not available, and the risk assessment is moderate, emphasizing the importance of regular inspections and maintenance to ensure its safety and functionality. With its scenic location and historical significance, Tioga Lake Main remains a key feature in the water resource and climate landscape of California.