The original dam, however, was made in dammed and watered layers, which still show distinctly in the wrecked dam. The new end greatly added to its stability, but it was to all appearances simply dumped in like an ordinary railroad fill, or if rammed, the wreck shows no evidence of the good effect of such work. Much of the old part is standing intact, while the adjacent parts of the new work are wholly carried off. There was no central wall of puddle or masonry either in the new or old dam. It has been the invariable practice of engineers for thirty or forty years to use one or the other in building high dams of earth. It is doubtful if there is a single dam or reservoir in any other part of the United States of over fifty feet in height which lacks this central wall.
Ignorance or Carelessness.
The reconstructed dam also bears the mark of great ignorance or carelessness in having been made nearly two feet lower in the middle than at the ends. It should rather have crowned in the middle, which would have concentrated the overflow, if it should occur, at the ends instead of in the centre. Had the break begun at the ends the cut of the water would have been so gradual that little or no harm might have resulted. Had the dam been cut at the ends when the water began running over the centre the sudden breaking would have been at least greatly diminished, possibly prolonged, so that little harm would have resulted. The crest of the old dam had not been raised in the reconstruction of 1881. The old overflow channel through the rock still remains, but owing to the sag of the crest in the middle of the dam only five and a half feet of water in it, instead of seven feet, was necessary to run the water over the crest.
And the rock spillway, narrow at best, had been further contracted by a close grating to prevent the escape of fish, capped by a good-sized timber, and in some slight degree also as a trestle footbridge. The original discharge pipe indicates that it was made about half earth and half rock, but if so there was little evidence of it in the broken dam. The riprapping was merely a skin on each face with more or less loose spauls mixed with the earth. The dam was seventy-two feet above water, two to one inside slope, one and a half to one outside slope and twenty feet wide on top. The rock throughout was about one foot below the surface. The earth was pretty good material for such a dam, if it was to be built at all, being of a clayey nature, making good puddle. To this the fact of it standing intact since 1881 must be ascribed, as no engineer of standing would have ever tried to so construct it. The fact that the dam was a reconstructed one after twenty years' abandonment made it especially hard on the older part of the dam to withstand the pressure of the water.
Elder Thought it was Safe.
Cyrus Elder, general counsel for the Cambria Iron Company and a wealthy and prominent citizen of Johnstown, lost a wife and daughter in the recent disaster and narrowly escaped with his own life.
"When the rebuilding of the dam was begun some years ago," he said, "the president of the Cambria Iron Company was very seriously concerned about it, and wished, if possible, to prevent its construction, referring the matter to the solicitor of the company. A gentleman of high scientific reputation, who was then one of the general engineers, inspected the dam. He condemned several matters in the way of construction and reported that this had been changed and that the dam was perfectly safe. My son, George R. Elder, was at that time a student in the Troy Polytechnic University.
"His professor submitted a problem to the class which he immediately recognized as being the question of the safety of the South Fork dam. He sent it to me at the time in a letter, which, of course, is lost, with everything else I possessed, in which he stated that the verdict of the class was that the dam was safe. The president of the Cambria Iron Company being still anxious, thought it might be good policy to have some one inside of the fishing and hunting corporation owning the dam. The funds of the company were therefore used to purchase two shares of its stock, which were placed in the name of D.J. Morrell. After his death these shares were transferred to and are still held by me, although they are the property of the Cambria Iron Company. They have not been sold because there was no market for them."
Untold Volumes of Water.
So far as the Signal Service is concerned, the amount of rainfall in the region drained by the Conemaugh river cannot be ascertained. The Signal Service authorities here, to whom the official there reported, received only partial reports last Friday. There had been a succession of rains nearly all of last week. The last rain commenced Thursday evening and was unusually severe.