Hells Canyon

Hells Canyon is a gravity dam located in Adams County, Idaho, built in 1967. It carries a High hazard potential classification and has a satisfactory condition assessment.

About Hells Canyon

The primary purpose of Hells Canyon is hydroelectric. The dam generates hydroelectric power by channeling water through turbines, converting the energy of flowing water into electricity. The dam is owned by Idaho Power Company (private). It impounds the Snake River near Rogerburg, Wa.

The dam stands 330 feet tall and stretches 910 feet across, creates a reservoir covering 2,430 acres, has a maximum storage capacity of 188,000 acre-feet, and collects water from a drainage area of 73,300 square miles. Completed in 1967, the structure is well into its service life at over 50 years old.

This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 09/28/2022.

At 330 feet, this dam is taller than 99% of all dams in the United States.

Living Downstream

If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Idaho dam safety program can provide more specific information about emergency planning for this structure.

Search for dams near your address to see all dams in your area with hazard classifications and safety data.

High HazardSatisfactory ConditionEmergency Action Plan: Yes

Location

StateIdaho
CountyAdams
Nearest CityRogerburg, Wa
River/StreamSnake River
Coordinates45.24310, -116.70050

Physical Characteristics

Dam TypeGravity
NID Height330 ft
Dam Height323 ft
Dam Length910 ft
Year Completed1967 (59 years old)

Storage & Hydraulics

NID Storage188,000 acre-ft
Max Storage188,000 acre-ft
Normal Storage170,000 acre-ft
Surface Area2,430 acres
Drainage Area73,300 sq mi
Max Discharge300,000 cfs
Spillway TypeControlled

Ownership & Safety

PurposeHydroelectric
OwnerIdaho Power Company
Owner TypePrivate
Hazard ClassificationHigh
Condition AssessmentSatisfactory
Last Inspection09/28/2022
Emergency Action PlanYes

Identifiers

NID IDID00055
Federal IDID00055
More InfoState Dam Safety Program