Johnson Lake Dam Reservoir Report

Last Updated: December 5, 2025

Johnson Lake Dam, located in Griffin, Georgia, is a private earth dam primarily built for recreational purposes.


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Summary

Constructed in 1955 by the Natural Resources Conservation Service, this dam stands at 26 feet tall with a hydraulic height of 19 feet, creating a reservoir with a storage capacity of 315 acre-feet. The dam spans 695 feet in length and covers a surface area of 23 acres, making it a popular destination for water enthusiasts and nature lovers alike.

Despite its age, Johnson Lake Dam has a low hazard potential and has not been rated for its condition assessment. While the dam has not undergone any recent modifications, it is inspected every five years to ensure its integrity and safety. The dam features an uncontrolled spillway and outlet gates, with no associated locks or drainage areas. The risk assessment for Johnson Lake Dam is moderate, indicating a level 3 risk classification, although specific risk management measures are not currently documented.

Overall, Johnson Lake Dam serves as an important recreational resource in Spalding County, providing opportunities for fishing, boating, and wildlife viewing. With its picturesque setting and historical significance, this dam continues to be a treasured landmark in the community, attracting visitors and water resource enthusiasts seeking to enjoy its natural beauty and amenities.

Year Completed

1955

Dam Length

695

Dam Height

26

River Or Stream

UNKNOWN

Primary Dam Type

Earth

Surface Area

23

Hydraulic Height

19

Nid Storage

315

Outlet Gates

Uncontrolled

Hazard Potential

Low

Foundations

Unlisted/Unknown

Nid Height

26
       
Seasonal Comparison

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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.