Hubbard Dam


Hubbard Dam, located about 12 miles southwest of Boise, Idaho, was originally constructed in 1902 by private interests. The Bureau of Reclamation purchased the facility in 1911 as part of the Boise Project. This is an earthfill structure 23 feet high creating a reservoir area of 450 acres with an active capacity of about 4,060 acre-feet. Water is delivered to the reservoir by the New York Canal. The dam and reservoir are operated and maintained by the Boise Project Board of Control as a reregulating facility for irrigation water deliveries in the adjacent area. It also provides emergency short-term storage for dewatering the New York Canal should a failure in the canal occur downstream. In 1998, as a result of a Safety of Dams investigation, the reservoir was restricted to a level of 2765.0 feet, with a capacity of 573 acre-feet.


Hubbard Dam is centrally located in the Western Snake River Plain (WSPR) physiographic province. The WSRP is a 50 to 70 km wide trough that trends northeast across southwestern Idaho. The WSRP is characterized by mid to late Cenozoic fluvial lacustrine sedimentation, voluminous basaltic volcanism, low relief and extremely low rates of seismicity.

RegionFacilities in Pacific Northwest | Pacific Northwest Home Page
Dam Type
WatercourseOffstream Storage
Location12 SW of Boise
Original Construction1902
Modified Construction
Hydrologic Unit Code

Structural Height23.0 ft
Hydraulic Height (Normal Operating Depth at Dam)19 ft
Top Parapet (Elevation)
Spillway Crest Elevation
Crest Elevation2780.0 ft
Crest Length
Crest Width
Base Width
Volume of Dam Construction Materials
Streambed at Dam Axis2757.3 ft
Top of Exclusive Flood Control Pool (Elevation)
Top of Joint Use Pool (Elevation)
Top of Active Conservation Pool (Elevation)2765.0 ft
Top of Inactive Conservation Pool (Elevation)
Top of Dead Storage Pool (Elevation)2757.3 ft

Hydraulics & Hydrology
Total Water Storage at Elevation
Maximum Water Surface Elevation
Normal Water Surface ElevationOriginally 2776.0 ft, currently restricted to 2765.0 ft
Spillway Type
Auxiliary SpillwayNo
Spillway Capacity at Elevation
Auxiliary Spillway Capacity at Elevation
Uncontrolled Spillway Capacity at Elevation
Outlet Works Capacity at Elevation25 cfs at 2765.0 ft (Outlet channel capacity)
Diversion Capacity at Elevation
Drainage Area2.55 sq mi
Hydrometeorological Report (HMR)HMR 43
Probable Maximum Flood (PMF) Report

Contact Information
TitleArea Office Manager
OrganizationSnake River Area Office
Address230 Collins Road
CityBoise, ID 83702-4520
Phone (Fax)208 383-2275
Phone (Office)208 383-2248
OrganizationBoise Project Board of Control
Address2465 Overland Road
CityBoise, ID 83705-3155
Phone (Office)208 344-1141

Last updated: Nov 26, 2012