Mystery Valley Lake Dam
Mystery Valley Lake Dam is an earth dam located in DeKalb County, Georgia, built in 1960. It carries a High hazard potential classification and has a poor condition assessment.
About Mystery Valley Lake Dam
The primary purpose of Mystery Valley Lake Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Dekalb County Roads & Drainage (local government). It impounds the Unknown.
The dam stands 24 feet tall and stretches 420 feet across, creates a reservoir covering 15 acres, and has a maximum storage capacity of 200 acre-feet. Completed in 1960, the structure is well into its service life at over 50 years old.
This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated poor, meaning the dam has recognized safety deficiencies that require remediation to address risks. Notably, no emergency action plan is currently on file for this high-hazard dam. The most recent inspection on record was 01/07/2021.
Living Downstream
If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Georgia dam safety program can provide more specific information about emergency planning for this structure.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Georgia |
| County | DeKalb |
| River/Stream | Unknown |
| Coordinates | 33.76472, -84.13278 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 24 ft |
| Dam Height | 24 ft |
| Dam Length | 420 ft |
| Year Completed | 1960 (66 years old) |
Storage & Hydraulics
| NID Storage | 200 acre-ft |
| Max Storage | 200 acre-ft |
| Normal Storage | 108 acre-ft |
| Surface Area | 15 acres |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Recreation |
| Owner | DeKalb County Roads & Drainage |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Poor |
| Last Inspection | 01/07/2021 |
| Emergency Action Plan | No |
Identifiers
| NID ID | GA03921 |
| Federal ID | GA03921 |
| More Info | State Dam Safety Program |