Anchor Dam

The dam is placed on fresh competent sandstone of the Tensleep Formation which  was grouted and concreted to seal joints and cavities in dolomite interbeds. Treatment by concreting and grouting  solution cavities and open joints has strengthened the foundation sufficiently to support the  weight of the dam. The seal provided by concreting and grouting in the Tensleep rocks is  probably effective only within a short radius of the dam foundation.

RegionFacilities in Great Plains | Great Plains Home Page
CountyHot Springs
ProjectOwl Creek
Dam Type
WatercourseSouth Fork, Owl Creek
Original Construction1957-1960
Modified Construction
National ID NumberWY01298
Hydrologic Unit Code

Structural Height208 ft
Hydraulic Height (Normal Operating Depth at Dam)146 ft
Top Parapet (Elevation)6456.42 ft
Spillway Crest Elevation
Crest Elevation6452.5 ft
Crest Length660 ft
Crest Width13.7 ft
Base Width54.2 ft
Volume of Dam Construction Materials69350 cu yd
Streambed at Dam Axis
Top of Exclusive Flood Control Pool (Elevation)
Top of Joint Use Pool (Elevation)
Top of Active Conservation Pool (Elevation)
Top of Inactive Conservation Pool (Elevation)
Top of Dead Storage Pool (Elevation)

Hydraulics & Hydrology
Total Water Storage at Elevation17354 acre-ft at 6441
Maximum Water Surface Elevation6463.3 ft
Normal Water Surface Elevation
Spillway Type
Auxiliary Spillway
Spillway Capacity at Elevation13500 cfs at 6451.5
Auxiliary Spillway Capacity at Elevation
Uncontrolled Spillway Capacity at Elevation
Outlet Works Capacity at Elevation500 cfs at 6441 ft
Diversion Capacity at Elevation
Drainage Area131 sq mi
Hydrometeorological Report (HMR)HMR 55A
Probable Maximum Flood (PMF) Report1991 June rain-on-snow

Contact Information
TitleFacility Manager
OrganizationBig Horn Basin Field Office
Address#4 Reclamation Road
CityCody, WY 82414
Phone (Office)307-527-6256 (ext. 260)
OrganizationOwl Creek Irrigation District
AddressPO Box 509
CityThermopolis, WY 82443
Phone (Fax)307 864-5116
Phone (Office)307 864-3015

Last updated: Mar 29, 2013