In 1899, a rock crib dam was built by E. P. Simpson on Tocco Creek to create a reservoir for a small hydroelectric power plant that began operating that same year.

[1] The power plant was transferred in 1933 to the Toccoa Falls Institute, which decided to develop a more stable electric power source and built an earthen embankment dam over the original rock crib dam between 1939 and 1940.

[2] After World War II, the dam was again raised, creating Barnes Lake, a 40-acre (16 ha) reservoir.

A low point on the right side and away from the dam could also be used as a secondary spillway when the reservoir levels became too high.

[4] The embankment dam was located about 2,000 feet (610 m) upstream from the Toccoa Falls and mostly consisted of residual soils and silt.

The dam sat on a foundation of silt and stable biotite gneiss (rock).

Two bridges on Toccoa Falls Drive and a culvert at County Farm Road were completely destroyed.