Johnson Reservoir Report

Last Updated: December 5, 2025

Johnson is a privately owned dam located in Brighton, Colorado, along the Brantner Gulch.


°F

°F

mph

Wind

%

Humidity

Summary

Built in 1927, this Earth-type dam is primarily used for irrigation purposes, with a height of 12 feet and a length of 309 feet. The dam has a storage capacity of 52 acre-feet and a normal storage of 40 acre-feet, serving as a crucial water resource in the area.

Despite its low hazard potential, Johnson has been rated as unsatisfactory in its condition assessment, with the last inspection conducted in September 2013. The dam poses a high risk, requiring attention to risk management measures to ensure the safety and integrity of the structure. While it is regulated by the Colorado Department of Water Resources and falls under state jurisdiction, the dam has not undergone any modifications in recent years.

Water resource and climate enthusiasts interested in the preservation and maintenance of dams like Johnson will find this data intriguing. As a key irrigation infrastructure in Adams County, Colorado, Johnson highlights the importance of regular inspection and risk assessment to safeguard water resources and ensure public safety. The dam's historical significance and its role in water management make it a focal point for ongoing monitoring and management efforts in the region.

Year Completed

1927

Dam Length

309

Dam Height

12

River Or Stream

BRANTNER GULCH

Primary Dam Type

Earth

Surface Area

4

Hydraulic Height

12

Nid Storage

52

Structural Height

12

Hazard Potential

Low

Nid Height

12
       
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.