Blackhawk Lake Reservoir Report

Last Updated: December 15, 2025

Blackhawk Lake, also known as Hait Dam (Upper), is a privately owned reservoir located in Valley County, Idaho.


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Summary

This dam on Duffner Creek, a tributary of the North Fork Payette River, was completed in 1968 for irrigation purposes. The earth dam stands at a height of 44.8 feet and has a hydraulic height of 39.5 feet, with a storage capacity of 1630 acre-feet and a surface area of 95 acres.

With a significant hazard potential and fair condition assessment, Blackhawk Lake is regulated by the Idaho Department of Water Resources. The dam features an uncontrolled spillway and slide gates for water release, with the last inspection conducted in May 2017. The risk assessment for the dam rates it as moderate, highlighting the importance of ongoing monitoring and maintenance to ensure the safety of the surrounding community and water resources in the area.

Blackhawk Lake serves as a vital water resource for irrigation in the region, supporting agricultural activities and providing water storage for the local community. Located in a picturesque setting near Payette River, this dam underscores the importance of sustainable water management practices in the face of changing climate conditions. Enthusiasts of water resources and climate will find Blackhawk Lake to be a fascinating example of human-built infrastructure interacting with the natural environment in a dynamic and critical way.

Year Completed

1968

Dam Length

490

Dam Height

44.8

River Or Stream

DUFFNER CREEK NORTH FORK PAYETTE RIVER

Surface Area

95

Hydraulic Height

39.5

Drainage Area

4

Nid Storage

1630

Outlet Gates

Slide (sluice gate)

Hazard Potential

Significant

Foundations

Rock, Soil

Nid Height

45
       
Seasonal Comparison

Weather Forecast

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. 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

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, 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.