Anita Dam

Anita Dam was not required in the original Huntley Project plans. Subsequent development of additional lands by local interests necessitated its construction for hold-over storage of water lifted by the turbine-driven pumps during slack periods, to reduce the extensive operating time of the pumps. this offstream storage dam was completed by the Civilian Conservation Corps (CCC) 1937. The dam is an earth structure, 42 feet high with a volume of 143,000 cubic yards, located 1 mile southeast of the Anita Railroad Station. The combination spillway-wasteway adjoining the High Line Canal on the north abutment is a concrete-lined chute 40 feet wide with a capacity of 1,500 cubic feet per second. The dam impounds a reservoir that has a capacity of 400 acre-feet.

RegionFacilities in Great Plains | Great Plains Home Page
Dam TypeModified homogeneous earthfill
WatercourseYellowstone River (offstream)
LocationOffstream, 6 miles southeast of Ballantine, Montana
Original Construction1933-1937
Modified Construction
National ID NumberMT00567
Hydrologic Unit Code

Structural Height42.00 ft
Hydraulic Height (Normal Operating Depth at Dam)30.00 ft
Top Parapet (Elevation)
Spillway Crest Elevation3,003.00 ft
Crest Elevation3,010.00 ft
Crest Length1,050.00 ft
Crest Width20.00 ft
Base Width252.00 ft
Volume of Dam Construction Materials143,000 cu yds
Streambed at Dam Axis
Top of Exclusive Flood Control Pool (Elevation)
Surcharge Storage (Elevation)3003.00 to 3007.80 ft
Top of Joint Use Pool (Elevation)
Top of Active Conservation Pool (Elevation)2,973.00 to 3003.00 ft
Top of Inactive Conservation Pool (Elevation)
Top of Dead Storage Pool (Elevation)

Hydraulics & Hydrology
Total Water Storage at Elevation400.00 acre-ft at 3,003.00 ft
Maximum Water Surface Elevation
Normal Water Surface Elevation3,003.00 ft
Spillway TypeUncontrolled concrete-lined chute at north abutment
Auxiliary Spillway
Spillway Capacity at Elevation 1,500.00 cfs at 3,007.80 ft
Auxiliary Spillway Capacity at Elevation
Uncontrolled Spillway Capacity at Elevation
Outlet Works Capacity at Elevation 50.00 cfs at 2,980.00 ft
Diversion Capacity at Elevation
Drainage Area
Hydrometeorological Report (HMR)
Probable Maximum Flood (PMF) Report

Contact Information
TitleArea Manager
OrganizationMontana Area Office
AddressP.O. Box 30137
CityBillings, MT 59107-0137
Phone (Fax)406 247-7338
Phone (Office)406 247-7300
OrganizationHuntley Project Irrigation District
AddressPO Box 61
CityBallantine, MT 59006
Phone (Office)406 967-3400

Last updated: Apr 05, 2013