Lake Thomas A Edison, lake of the United States of America

Lake Thomas A Edison is a reservoir in the Sierra National Forest, Fresno County, held back by the earthen Vermilion Valley Dam, 4,234 feet long and 167 feet high. It lies at 2,331 metres in the Sierra Nevada, covers 6.3 square kilometres, and drains into Mono Creek. Its shore is lined with pine forest, and Recess Peak rises about 10.7 km to the east.

The reservoir was created by damming in the mid-20th century, with completion in 1954, to store water for the community and irrigation purposes. It became part of a network of lakes supplying water across the region and supporting local development.

The lake bears the name of Thomas A. Edison, the inventor and industrialist who transformed electricity and power generation. This naming reflects the connection between the reservoir and the region's energy history.

The lake is about three hours by car from Fresno via State Route 168 east to Huntington Lake, then Kaiser Pass Road over Kaiser Pass (9,175 ft). The road closes in winter and the Forest Service does not recommend it for buses, large motor homes, or vehicles towing trailers. A ferry crosses the lake twice a day, linking Vermilion Valley Resort with the John Muir Wilderness trailhead; when water is low, hikers can follow a trail along the north side.

The reservoir is named for Thomas Edison, marking the 75th anniversary of his incandescent light bulb, while the dam takes its name from the flooded Vermilion Valley, noted for its reddish soil. The lake discharges into Mono Creek, but some water is diverted to Huntington Lake through the Ward Tunnel.