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located 226 feet downstream, (d) 7 points located 350 feet downstream, and (e) 3 points located 400 feet downstream. At the main embankment section, station 160+00 to station 178+00, the lines of points 25 feet upstream and 50 feet downstream are located on 100foot centers. Distances between the remainder of the points vary from 75 to 400 feet.
The points consist of 3-foot lengths of 1-inch-square steel reinforcement bars driven into the surface of the dam at the prescribed locations. A pointed bar was driven into the embankment at the desired location. This bar was then removed and the 1-inch-square reinforcement bar was driven into the hole. The top of the bar was allowed to extend between 3 and 6 inches above the surface. A hole 1 foot deep and 1 foot in diameter was then excavated around the bar and filled with concrete to insure firm anchorage, After the concrete had set, crosses were chiseled on top of the bars for station, elevation, and alinement readings. Elevations of these points were tied into the benchmarks shown in figure 33 and to others farther from the dam.