South Atlantic Water Science Center - Georgia
1997 Toccoa Flood
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The 1977 Toccoa Flood, Report of Failure of Kelly Barnes Dam Flood and Findings
by Federal Investigative Board
December 21, 1977
The Kelly Barnes Dam failed about 1:30 a.m., on November 6, 1977. The dam went through various stages of development. First as a rock crib dam and then with subsequent stages as an earth dam. The rock crib dam was completed about 1899 to back up water which would be used to power a small hydroelectric plant located near the foot of the Falls. About 1937, the Toccoa Falls Bible Institute was interested in developing a more dependable power source and decided to build an earth dam over the rock crib dam. This construction was performed with equipment provided by a local manufacturer. After World War II, the earth fill was raised to a point where an earth spillway on the left side of the valley could be utilized, and a low point on the rim on the right side away from the dam would serve as an secondary spillway in case high flows occurred.
The final height of the dam was approximately 42 feet above the rock foundation. This installation served as a power source until 1957 for the Toccoa Falls Bible Institute, which later became the Toccoa Falls College. At this time, the development of power was stopped but the dam continued to be used as a recreation lake.
The Board could not determine a sole cause of the November 6, failure. It does conclude that a combination of factors caused the failure. The most probable causes are a local slide on the steep downstream slope probably associated with piping, an attendant localized breach in the crest followed by progressive erosion, saturation of the downstream embankment, and subsequently a total collapse of the structure.
The Board wishes to acknowledge its grateful appreciation to all the individuals, organizations, and groups that supplied information and assistance of any kind to this effort. This includes the following contributors: