Located between the cities of Folsom and El Dorado Hills along Green Valley Road, the Mormon Island Auxilliary Dam is an important component to the Folsom Facility, which includes Folsom’s concrete and left and right wings dams and eight earthfill dikes, each of which serves to impound water to create Folsom Reservoir. The dam is a Folsom Project built by the U.S. Army Corps of Engineers from 1948 to 1956. Operation and maintenance was transferred to Reclamation in May 1956. The Mormon Island Auxilliary Dam is a zoned earthfill embankment dam, wiht a crest elevation of 480 feet, and it is 110 feet high and 4,820 feet long.
General
Project
CVP-Folsom Sly Park
Longitude
-121.1222
Latitude
38.7081
Watercourse
Blue Ravine
Original Construction
1956
National ID Number
CA10153
Base Width
270 ft
Dimensions
Top Parapet (Elevation)
105.0 ft
Structural Height
110.0 ft
Crest Length
4820.0 ft
Hydraulics & Hydrology
Drainage Area
1875 sq mi
Contact
More Information about the U.S. Bureau of Reclamation