Deerfield Dam

Deerfield Dam is located within the Precambrian core in the southeastern portion of the Black Hills Uplift.  It is situated between two bluffs composed primarily of steeply dipping phyllite and quartz mica schist.  The structural attitude of the bedding and scistosity indicate that the site is located near the plunging crest of an overturned major fold.  Change in foliation trends at the site indicate that Precambrian folding and faulting on a minor have also occurred.  The foliation or schistosity tends to parallel the hillside on the left abutment and dips obliquely upstream across the dam into the right abutment.  Because weathering tends to follow down the foliation planes, rock on the left abutment was found to be generally hard, moderately fractured and had shallow weathering, while rock through the stream channel and the right abutment was highly fractured and weathered to depths in excess of 30 feet.  The original valley floor consisted of an organic silt about 4 feet thick overlying 10 to 15 feet of water-bearing sand and gravel.

RegionFacilities in Great Plains | Great Plains Home Page
StateSouth Dakota
ProjectRapid Valley
Dam Type
WatercourseCastle Creek
Original Construction1942-1947
Modified Construction1982-1984
National ID NumberSD01138
Hydrologic Unit Code

Structural Height171.00 ft
Hydraulic Height (Normal Operating Depth at Dam)
Top Parapet (Elevation)
Spillway Crest Elevation5912.00 ft
Crest Elevation5958.00 ft
Crest Length1125.00 ft
Crest Width
Base Width
Volume of Dam Construction Materials
Streambed at Dam Axis5808.00 ft
Top of Exclusive Flood Control Pool (Elevation)
Top of Joint Use Pool (Elevation)
Top of Active Conservation Pool (Elevation)5908.00 ft
Top of Inactive Conservation Pool (Elevation)
Top of Dead Storage Pool (Elevation)5839.00 ft

Hydraulics & Hydrology
Total Water Storage at Elevation
Maximum Water Surface Elevation
Normal Water Surface Elevation5908.0 ft
Spillway Type
Auxiliary SpillwayNo
Spillway Capacity at Elevation103400.0 cfs at 5953.0 ft
Auxiliary Spillway Capacity at Elevation
Uncontrolled Spillway Capacity at Elevation
Outlet Works Capacity at Elevation280.0 cfs at 5915.0 ft
Diversion Capacity at Elevation
Drainage Area
Hydrometeorological Report (HMR)
Probable Maximum Flood (PMF) Report

Contact Information
TitleArea Office Manager
OrganizationDakotas Area Office
AddressPO Box 1017
CityBismarck, ND 58501
Phone (Fax)701 250-4326
Phone (Office)701 250-4242
OrganizationHanover Irrigation District
AddressPO Box 965
CityWorland, WY 82401
Phone (Office)307 347-3134

Last updated: Mar 29, 2013