Black Canyon Diversion Reservoir Report
Last Updated: December 19, 2025
Black Canyon Diversion is a key water infrastructure located in Gem County, Idaho, along the Payette River.
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Summary
Built in 1923, this concrete gravity dam stands at 183 feet tall and serves multiple purposes, including hydroelectric power generation and irrigation. Managed by the Bureau of Reclamation, the dam has a storage capacity of 29,822 acre-feet and a maximum discharge of 39,060 cubic feet per second.
With a high hazard potential and very high risk assessment rating, Black Canyon Diversion plays a critical role in managing water resources in the region. Its controlled spillway and advanced engineering make it a vital piece of infrastructure for water management and flood control. The dam is regularly inspected and regulated by the Bureau of Reclamation to ensure its safe operation and maintenance.
Black Canyon Diversion is not only a functional piece of infrastructure for water resource management but also a historic landmark in Idaho's landscape. Its impact on the local environment and communities underscores the importance of sustainable water management practices in the face of changing climate patterns. As water resource enthusiasts, understanding the significance of structures like Black Canyon Diversion is crucial for promoting resilience and conservation in the face of evolving climate challenges.
Year Completed |
1923 |
Dam Length |
1040 |
Dam Height |
183 |
River Or Stream |
PAYETTE RIVER |
Primary Dam Type |
Concrete |
Surface Area |
1100 |
Hydraulic Height |
112 |
Drainage Area |
2680 |
Nid Storage |
29822 |
Structural Height |
183 |
Hazard Potential |
High |
Foundations |
Rock |
Nid Height |
183 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Payette River Nr Emmett Id
|
1660cfs |
Payette River Nr Letha Id
|
1520cfs |
Payette River Nr Horseshoe Bend Id
|
2790cfs |
Spring Valley Creek Nr Eagle Id
|
0cfs |
Dry Creek Nr Eagle Id
|
0cfs |
Eagle Drain At Eagle
|
7cfs |
Dam Data Reference
Condition Assessment
SatisfactoryNo 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. Note: Rare or extreme event is defined by the regulatory agency based on their minimum
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. Investigations and studies are necessary.
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.
Not Available
Dams for which the condition assessment is restricted to approved government users.
Hazard Potential Classification
HighDams 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, environment 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.
Not Available
Dams for which the downstream hazard potential is restricted to approved government users.
Black Canyon Diversion