Hells Canyon dam
Hells Canyon
Hells Canyon, located in Idaho along the Snake River, is a privately owned hydroelectric dam that was completed in 1967. This gravity dam stands at a height of 323 feet, with a structural height of 330 feet and a length of 910 feet. With a normal storage capacity of 170,000 acre-feet and a maximum storage of 188,000 acre-feet, the dam covers a surface area of 2,430 acres and serves multiple purposes including hydroelectric power generation, navigation, and recreation.
Managed by the Federal Energy Regulatory Commission, Hells Canyon Dam has a controlled spillway with a width of 159 feet and five Tainter (radial) gates for outlet control. The dam's hazard potential is classified as high, with a very high risk assessment rating. While the condition assessment is not available, the dam's emergency action plan was last revised in April 2021. With its impressive engineering design and significant impact on the surrounding environment and water resources, Hells Canyon Dam remains a notable structure for water resource and climate enthusiasts to study and explore in the picturesque setting of Adams County, Idaho.
Dam data reference
Condition Assessment
- Satisfactory
- No existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
- Fair
- No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action.
- Poor
- A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency.
- Unsatisfactory
- A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
- Not Rated
- The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Hazard Potential Classification
- High
- Dams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
- Significant
- Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environmental damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
- Low
- Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
- Undetermined
- Dams for which a downstream hazard potential has not been designated or is not provided.
Plan around the weather
Same NOAA / yr.no feed Snoflo's iOS app uses. Watch the precipitation column on the meteogram -- rain on the basin upstream typically lifts inflow 24-72 hours later.
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind. Each cell is colour-coded relative to the column min/max.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day temperature & precipitation
Daily temperatures, snow, and rain projected over the next two weeks.
Nearby streamflow gauges
USGS streamgauges around Hells Canyon -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Snake River At Hells Canyon Dam Id-Or State Line | 19,200 cfs | → |
| Little Salmon River At Riggins Id | 1,950 cfs | → |
| Imnaha River At Imnaha | 150 cfs | → |
| Nf Payette River At Mccall Id | 997 cfs | → |
| Salmon River At White Bird Id | 23,300 cfs | → |
| Lake Fork Payette River Ab Jumbo Cr Nr Mccall Id | 596 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Hells Canyon.
Boat launches
- Hells Canyon Creek Recreation Site
- Allison Creek Trail Adams County
- Copper Creek Boat Launch
- Hells Canyon Road Adams County
- Bob Creek
- Copperfield Boat Launch
Campgrounds
- Stud Creek Campsite
- Lamont Springs Campsite
- Square Beach Campsite
- Brush Creek Campsite
- Rocky Point Campsite
- Chimney Bar Campsite
Track Hells Canyon in the Snoflo app
Save this dam as a favorite and get the local NOAA / yr.no forecast plus regional flow context wherever you are.
About Hells Canyon
Where does the data for Hells Canyon come from?
Structural and regulatory data come from the U.S. Army Corps of Engineers' National Inventory of Dams (NID). Weather forecast comes from NOAA / yr.no -- the same feed Snoflo's iOS app uses.
How often is the report updated?
NID structural data refreshes annually as the Corps publishes updated assessments. The weather forecast refreshes throughout the day.
What does the High hazard rating mean?
The Corps of Engineers' hazard potential classification grades probable consequences if the dam fails: High = probable loss of human life; Significant = no probable loss of human life but possible economic loss / environmental damage; Low = no probable loss of human life, only minor economic / environmental losses. See the Dam Data Reference card above for the full definitions.
What's "% of normal"?
The current storage value compared to the historical average storage on this calendar day. 100% = right on average; values above 100% mean above-normal storage (wet year); values below mean below-normal (dry year or drought).
Can I get alerts when storage crosses a threshold?
Yes -- alerts are managed in the Snoflo iOS app. Favorite this dam, set a threshold, and you'll get a push the moment conditions cross.
Other water bodies near here
Snoflo-tracked reservoirs and dams within driving distance of Hells Canyon.