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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

HISTORY

The history of the Kelly Barnes Dam as reconstructed, based on review of old records, maps, college albums, newspaper accounts, photographs, and interviews with historical witnesses, is as follows:

1. In 1899 a rock crib dam, constructed by Mr. E. P. Simpson, was completed at the present dam site. This dam furnished water to a small power plant known as the Toccoa Falls Light and Power Company (Photo 1). This plant is still located on what is now the Toccoa Falls College campus. Water for the power plant was delivered from the dam through a spiral riveted pipe (penstock) approximately 30-inches in diameter.

2. In the early 1930's, Mr. Kelly Barnes, then the Business Manager for Toccoa Falls Institute (forerunner of the Toccoa Falls College), acquired the land for the school which included the E. P. Simpson Power Dam and another dam further upstream. An inspection of the upstream dam during the investigation revealed that it had been inoperative for a number of years and had no effect on the Kelly Barnes Dam. Records indicate it was destroyed by a runoff event in 1929. An earth fill dam was constructed at the site of the E. P. Simpson Dam in the period of 1939-1940. This earth dam incorporated all, or part of, the old crib dam into its downstream toe. Construction was accomplished using equipment reportedly furnished by the LeTourneau Company of Toccoa, manufacturer of self-powered earth scrapers. Conflicting information has been received, but the machinery apparently was operated by local persons, some of whom may have been students trained at the school. Prior to placing the earth fill, attempts may have been made to remove sediments that had accumulated behind the old crib dam. However, comments by historical witnesses, and evidence visible at the site after the recent failure, indicate that this removal was not extensive or complete. The fill was reportedly placed in layers and rolled by the movement of rubber-tired scrapers and a track-mounted dozer. According to witnesses, a low-level spillway outlet, consisting of a 30-inch metal pipe, was placed through the dam along the streambed with its inlet located on the upstream slope. The exact location, elevation, and configuration of this low-level spillway has not been established. There is also some question as to whether or not the spiral riveted penstock in the vicinity of the dam was replaced during this period. This dam became known as the Kelly Barnes Dam.

3. The March, 1946 issue of the Toccoa Falls News, the school newspaper, carries the story of a dam bursting approximately one mile above the school. This dam, said to be the McNeely Dam by a historical witness, was located on Dead Man's Branch and would not have affected the Kelly Barnes Dam.

4. The June, 1948 issue of the Toccoa Falls News contains a reference to a new dam being constructed about one-half mile above the Falls. This is the location of the Kelly Barnes Dam. It may not have been a new dam but an addition or repair to the existing dam (Photo 2). Photographs were taken by a construction worker who welded the outlet pipes and who was also a student at Toccoa Falls College. These photographs, developed in 1949 (Photo 3) show the crest of the dam as construction progressed with separate inlets for a low-level spillway and a welded steel penstock to the power plant. The low-level spillway had a rectangular shaped masonry inlet which could be shut off with stop logs or flashboards. The inlet for the welded steel penstock was also masonry and controlled with a slide gate at the upstream toe of the dam. The approximate location of these inlets are shown on Figure 1.

Map showing approximate location of these inlets.
Fig. 2--Survey of lake, dam, and penstock location from student survey of college

Some historical witnesses remember the penstock slide gate but do not recall the masonry structure. After the failure, this gate was retrieved from below the dam site and found to be closed. The conduits for the spillway outlet and new penstock were both welded plate pipes approximately 30-inches in diameter. A historical witness stated that during placement of fill over the spillway conduit, the pipe began to cave in and had to be reinforced with metal struts. Descriptions of the earth fill construction and equipment are similar to the construction which occurred in the 1930's (Photo 2). At this time or during previous construction, the old spiral riveted penstock pipe had been abandoned but not removed. Conflicting information suggests the possibility of a series of construction events during the 1940's. A 1954 Survey of Buildings, Roads, Streams, and Lakes of the Toccoa Falls Institute (Figure 2) locates the overflow pipe (low-level spillway), a 24-inch conduit (welded steel penstock), and the intake structures.

5. Information available indicates that the fill was constructed to its final height in the late forties. However, a study of stereo-pairs of aerial photographs taken on January 17, 1955 shows the reservoir to be essentially empty at that time. The inlet structures, two earth spillways, and the pipe leading to the powerhouse are clearly visible. In later years a heavy growth of vegetation became established on both the upstream and downstream face and apparently obliterated the masonry intakes from view. Again, information received from historical witnesses conflicts as to whether or not two structures existed at the time of failure. Judging from the debris found downstream and the remains of the welded steel penstock, it is the Board's opinion that both existed at the time of failure.

6. A number of observers informed the Board of seeing almost continual seepage on the downstream slope of the dam near the point of exit of the spillway pipe. Photographs obtained from one source taken in 1973 show that a large embankment slide had occurred on the downstream face of the dam (Photos 12 and 13). This 12-foot high, 30-foot wide slide of unknown depth, was observed on the lower one-third of the downstream slope in the area of the current failure section, which was the highest point of the dam. The slide left a two-foot, vertical, scarp face and partially exposed the end of a pipe. The slide, at the time of the photograph, was apparently not recent because of the existance of established vegetation on the slide area. The picture shows the pipe to be essentially clogged with silt and trash, but a very slight seepage was observed coming from the pipe. The area near the pipe contained water that was discolored by iron oxide, sulfur, or some oth er matter indicating little or no flow. The area adjacent to the recent dam failure was wet and spongy a week after the failure and seepage water was still coming from the toe near the right abutment (looking downstream) at that time.

7. In May, 1976, Toccoa Creek flooded below the Falls. Many other small rivers in the region also flooded, doing considerable damage to roads, bridges, and farm lands. The area was declared eligible for Federal Disaster Relief. Federal agencies examined the area and authorized $30,000 for repairs to roads of Toccoa Falls College. There was no reported inspection of the dam at that time. It is likely that the flooding was from local inflow of tributaries below Toccoa Falls as well as from the Toccoa Creek above the dam.

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