General

• Region (Map) : .................. Pacific Northwest
• State (Map) ........................ Idaho
• County ................................ Fremont
• Project: ................................ Minidoka
• Dam type: ........................... Earthfill
• Location: ............................ 38 mi N of Ashton
• Watercourse: ..................... Henrys Fork
• Reservoir: ........................... Island Park
• Construction Date: ............1935-1938
• National ID Number .......... ID00272
• Hydrologic Unit Code ....

Dimensions

• Crest Elevation of Dam: ...................... 6309.0 ft
• Structural Height of Dam: ....................... 91.0 ft
• Crest Length: ........................................ 9450.0 ft
• Top of Joint Use: .......................................... NA
• Top of Active Conservation: ............. 6302.0 ft
• Top of Inactive Conservation: ............6239.0 ft
• Spillway Crest: .......................................6302.0 ft
• Top of Dead Storage: .......................... 6230.0 ft
• Streambed at Dam Axis : ..................... 6228.0 ft

Hydraulics

• Normal Water Surface Elev: ............... 6302.0 ft
• Hydraulic Height: .................................... 81.0 ft
• Service Spillway Type:
•    Uncontrolled  Crest    ............................... Yes
•    Morning-Glory ........................................... No
•    Crest Length    .................................... 257.0 ft
•    Gated      ....................................................... No
•    Capacity at Elev: 6305.0  ft,               5,000 cfs
• Auxiliary Spillway ......................................... No
•     Capacity at Elev.   .................................... NA
• Outlet Works Capacity at
•     Elevation  6302.0 ft.,  .......................3,400 cfs

Hydrology

• Drainage Area: ................................. 482.0 sq mi
• Hydrometeorological Report (HMR)  HMR-NA
• Flood Type: ............................... Winter General
• Storm Duration: ......................................... 72 hrs
• Probable Maximum Flood (PMF) Report:
•   Peak Inflow: ...................................... 33,700 cfs
•   Inflow Volume: ........................... 96,700 acre-ft
•   Flow Duration: ....................................... 8 days
•   PMF Routing MWS Elev.: ........................ NA
•   Initial Routing Elev: ........................... 6302.0 ft
•   Study Date: ................................... March 1967