Lake Thomas A Edison

Lake Thomas A Edison (also known as Thomas A. Edison Lake^[1] and Edison Lake) is a reservoir in the Sierra National Forest and in Fresno County, California. It is in the Sierra Nevada, and near the Pacific Crest Trail.

Lake Thomas A Edison
Lake Thomas A Edison Show map of California Lake Thomas A Edison Show map of the United States
Location	Fresno County, California[1]
Coordinates	37°22′58″N 118°58′34″W[1]
Type	Reservoir
Primary inflows	Mono Creek, Cold Creek
Primary outflows	Mono Creek[2]
Catchment area	88 square miles (230 km2)[2]
Basin countries	United States
Max. length	3.5 miles (5.6 km)
Max. width	1 mile (1.6 km)
Surface area	1,878 acres (760 ha)[2]
Average depth	67 feet (20 m)
Water volume	125,000 acre-feet (154,000,000 m3)[2]
Shore length1	13 miles (21 km)[3]
Surface elevation	7,648 feet (2,331 m)[1]
1 Shore length is not a well-defined measure.

The reservoir's waters are impounded by Vermilion Valley Dam (National ID CA00441), which was completed in 1954 (71 years ago) (1954).^[2] The reservoir and dam are part of the Big Creek Hydroelectric Project.

Hydrology

The reservoir discharges into Mono Creek,^[2] a tributary of the South Fork San Joaquin River. However, some of its water is diverted to Huntington Lake by means of the Ward Tunnel.^[4]

Vermilion Valley Dam

Vermilion Valley Dam
Country	United States
Location	Fresno County, California
Coordinates	37°22′12″N 118°59′14″W
Opening date	1954
Owner(s)	Southern California Edison
Dam and spillways
Type of dam	Earthen
Impounds	Mono Creek[2]
Height	167 feet (51 m)[2]
Length	4,234 feet (1,291 m)[2]
Elevation at crest	7,650.5 feet (2,331.9 m)[2]
Width (crest)	20 feet (6.1 m)[2]
Dam volume	4,200,000 cubic yards (3,200,000 m3)[2]
Reservoir
Creates	Lake Thomas A Edison
Total capacity	125,000 acre-feet (154,000,000 m3)[2]
Catchment area	88 square miles (230 km2)[2]
Maximum length	3.5 miles (5.6 km)
Maximum width	1 mile (1.6 km)

Vermilion Valley Dam is an earthen dam 4,234 feet (1,291 m) long and 167 feet (51 m) high, with 8 feet (2.4 m) of freeboard. Southern California Edison owns the dam.^[2]

Recreation

Located in Sierra National Forest near the Pacific Crest Trail, Lake Thomas A Edison is the centerpiece of Vermilion Valley Resort and Vermillion Campground, which support boating, camping, fishing, swimming, canoeing, kayaking, and horseback riding.^[3][5]

Access

The lake is three hours away by car from Fresno. Take State Route 168 east to Huntington Lake, head east on Kaiser Pass Road. The road crosses Kaiser Pass (elevation 9,175 feet (2,797 m)) and closes during the winter months. The United States Forest Service does not recommend it for buses, large motor homes, or vehicles towing trailers.^[6]

A ferry crosses the lake twice a day (Inactive in 2021 due to extreme low levels of water - travel service to/from the trailhead can be arranged through Vermillion Valley Resort or hikers may follow a trail along the north side of the lake for trail access), linking Vermilion Valley Resort with the John Muir Wilderness trailhead and providing access to and from the John Muir Trail and Pacific Crest Trail.^[6]

Nomenclature

The lake was named after American inventor Thomas Edison to mark the 75th anniversary of his invention of the incandescent light bulb.^[7] The dam was named after the valley it flooded, noted for its reddish soil.^[6]

See also

• List of dams and reservoirs in California
• List of lakes in California

Lake Edison, aerial looking northeast

Lake Edison, southern shoreline looking north. Taken from the edge of the lake when the lake is at full capacity.