Longs Peak #2 Reservoir Report

Last Updated: December 5, 2025

Located in Boulder, Colorado, Longs Peak #2 is a privately owned Earth dam that was completed in 1968 with a primary purpose of serving as a Fish and Wildlife Pond.


°F

°F

mph

Wind

%

Humidity

Summary

With a dam height of 41 feet and a hydraulic height of 40 feet, this structure has a normal storage capacity of 286 acre-feet and a maximum storage capacity of 376 acre-feet. The dam spans a length of 2230 feet and has a surface area of 12 acres, making it an important resource for both recreation and conservation efforts.

Managed by the Colorado Department of Water Resources, Longs Peak #2 is regulated and inspected on a regular basis to ensure its safety and compliance with state standards. Despite its low hazard potential and satisfactory condition assessment, the dam poses a moderate risk level, indicating the need for ongoing risk management measures. With a maximum discharge capacity of 800 cubic feet per second and an uncontrolled spillway type, this dam plays a crucial role in maintaining the ecological balance of the St. Vrain Creek-OS watershed.

Overall, Longs Peak #2 serves as a vital component of the local water resource infrastructure, providing not only recreational opportunities but also essential habitat for fish and wildlife in the area. As climate change continues to impact water availability and quality, the proper management and maintenance of structures like Longs Peak #2 are essential in ensuring the long-term sustainability of our water resources and ecosystems.

Year Completed

1968

Dam Length

2230

Dam Height

41

River Or Stream

ST. VRAIN CREEK-OS

Primary Dam Type

Earth

Surface Area

12

Hydraulic Height

40

Nid Storage

376

Structural Height

51

Hazard Potential

Low

Nid Height

51
       
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.