Big Sandy Dam


Big Sandy Dam is on Big Sandy Creek 10 miles north of Farson, Wyoming. It is a zoned earthfill dam 85 feet high, having a crest length of 2,350 feet and containing about 840,000 cubic yards of material. The uncontrolled open side-channel spillway has a capacity of 7,350 cubic feet per second.

The outlet works, consisting of a concrete conduit through the base of the dam controlled by two high-pressure slide gates, has a capacity of 620 cubic feet per second. An earthfill dike with a maximum height of 18 feet, 8,300 feet long, and containing 107,000 cubic yards of material lies north of the left abutment of the dam along the eastern rim of the reservoir basin.

RegionFacilities in Upper Colorado | Upper Colorado Home Page
Dam Type
ReservoirBig Sandy
WatercourseBig Sandy Creek
Original Construction1941-1952
Modified Construction
National ID NumberWY01387
Hydrologic Unit Code

Structural Height85.0 ft
Hydraulic Height (Normal Operating Depth at Dam)62.8 ft
Top Parapet (Elevation)
Spillway Crest Elevation6757.5 ft
Crest Elevation6769.0 ft
Crest Length2350.0 ft
Crest Width
Base Width
Volume of Dam Construction Materials840,000 cu. yards
Streambed at Dam Axis6700.0 ft
Top of Exclusive Flood Control Pool (Elevation)
Top of Joint Use Pool (Elevation)
Top of Active Conservation Pool (Elevation)6757.5 ft
Top of Inactive Conservation Pool (Elevation)
Top of Dead Storage Pool (Elevation)6720.0 ft

Hydraulics & Hydrology
Total Water Storage at Elevation
Maximum Water Surface Elevation6762.8 ft
Normal Water Surface Elevation
Spillway Type
Auxiliary SpillwayNo
Spillway Capacity at Elevation7350 cfs at 6762.8 ft
Auxiliary Spillway Capacity at Elevation
Uncontrolled Spillway Capacity at Elevation
Outlet Works Capacity at Elevation635 cfs at 6762.8 ft
Diversion Capacity at Elevation
Drainage Area399.0 sq mi
Hydrometeorological Report (HMR)HMR 49
Probable Maximum Flood (PMF) Report

Contact Information
TitleArea Office Manager
OrganizationProvo Area Office
Address302 East 1860 South
CityProvo, UT 84606-7317
Phone (Office)801 379-1101
OrganizationEden Valley Irrigation and Drainage District
Address13 Highway #28
CityFarson, WY 82932
Fax307 273-9567
Phone (Office)307 273-9566

Last updated: Mar 27, 2009