Anita Dam

Overview

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.

General

Region	Facilities in Great Plains \| Great Plains Home Page
State	Montana
County	Yellowstone
Project	Huntley
Dam Type	Modified homogeneous earthfill
Reservoir	Anita
Watercourse	Yellowstone River (offstream)
Location	Offstream, 6 miles southeast of Ballantine, Montana
Longitude	-108.0007553100586
Latitude	45.933431151319745
Original Construction	1933-1937
Modified Construction
National ID Number	MT00567
Hydrologic Unit Code

Dimensions

Structural Height	42.00 ft
Hydraulic Height (Normal Operating Depth at Dam)	30.00 ft
Top Parapet (Elevation)
Spillway Crest Elevation	3,003.00 ft
Crest Elevation	3,010.00 ft
Crest Length	1,050.00 ft
Crest Width	20.00 ft
Base Width	252.00 ft
Volume of Dam Construction Materials	143,000 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 Elevation	400.00 acre-ft at 3,003.00 ft
Maximum Water Surface Elevation
Normal Water Surface Elevation	3,003.00 ft
Spillway Type	Uncontrolled 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

Owner

Title	Area Manager
Organization	Montana Area Office
Address	P.O. Box 30137
City	Billings, MT 59107-0137
Phone (Fax)	406 247-7338
Phone (Office)	406 247-7300

Operator

Organization	Huntley Project Irrigation District
Address	PO Box 61
City	Ballantine, MT 59006
Phone (Office)	406 967-3400

Last updated: Apr 05, 2013