Lake John D Long

About Lake John D Long

The primary purpose of Lake John D Long is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Sc Department Of Natural Resources (state). It impounds the Hughes Creek.

The dam stands 49 feet tall, creates a reservoir covering 81 acres, and has a maximum storage capacity of 2,109 acre-feet. Completed in 1978, the structure is 48 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 fair — the dam has minor deficiencies that are being addressed or do not pose an immediate safety threat. An emergency action plan is in place for this dam. The most recent inspection on record was 06/11/2024.

At 49 feet, this dam is taller than 92% of dams nationwide.

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 South Carolina dam safety program can provide more specific information about emergency planning for this structure.

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