Black Lake #1 Reservoir Report

Last Updated: December 4, 2025

Black Lake #1, located in Eagle County, Colorado, is a public utility dam on Black Gore Creek, serving primarily for water supply.


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Summary

Built in 1939, this earth dam stands at 31 feet tall with a hydraulic height of 25 feet and a structural height of 73 feet, providing a storage capacity of 642 acre-feet. The dam has a surface area of 28 acres and a drainage area of 1 square mile, with a maximum discharge capacity of 3600 cubic feet per second.

Despite being categorized as having a high hazard potential, Black Lake #1 is currently assessed to be in fair condition as of the last inspection in July 2020. The dam has undergone modifications in 1993 to improve its foundation, hydraulic, mechanical, and structural components. With an emergency action plan in place and regular inspections conducted, the dam is managed to mitigate risks and ensure the safety of surrounding communities in the event of a potential failure. Overall, Black Lake #1 serves as a vital infrastructure for water management in the region, highlighting the importance of sustainable water resource practices in the face of climate challenges.

Years Modified

1993 - Foundation, 1993 - Hydraulic, 1993 - Mechanical, 1993 - Other, 1993 - Structural

Year Completed

1939

Dam Length

400

Dam Height

31

River Or Stream

BLACK GORE CREEK

Primary Dam Type

Earth

Surface Area

28

Hydraulic Height

25

Drainage Area

1

Nid Storage

642

Structural Height

73

Outlet Gates

Slide (sluice gate) - 1

Hazard Potential

High

Foundations

Rock, Soil

Nid Height

73
       
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.