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Page:Popular Science Monthly Volume 73.djvu/304

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THE POPULAR SCIENCE MONTHLY

described, consequently there can be no difference whatsoever from what point of the basin the water is diverted.

14. Water taken from One Side of Basin affects the Other Side.—That water can not be taken from one side of the basin without affecting the level on the other side is shown by the fact that, since the two New York companies began operations, the depth of the river, which is a mile across, near the mouth of Chippawa Creek, has been shoaled to the extent of eight or ten feet by the deposit of mud, owing to the slackened current in this part of the basin. So, also, when the power of the Ontario Company comes to be fully used, they will lower the water on the American Falls. Another proof of the diversion of water from the Canadian shore by the New York companies is the shoaling of the river just above the falls, where it was found necessary to throw a barrier to catch the water for the small local power plant, as the level of the river had sunk below the normal stage by the time one of the larger Canadian power plants was ready to begin operations.

15. Power Diversion below the Upper Rapids.—There are two other power plants situated in the Canadian Park, but below the Upper Rapids. Consequently, they lose much by their inferior head of water. This is a great gain, in that, taking the water some fifty feet below the basin, the overflow of the rim is not increased, so that this diversion produces no effect whatever on the lowering of the lake levels, or on the American Falls, or eastern side of the Canadian. These companies take the water from the deepest part of the channel, and consequently their effect is least apparent. Their aggregate allowance is about 20,000 cubic feet per second, or a net of 235,000 electric horse-power. However, much damage has been done to the western side of the falls, largely owing to the Canadian Niagara Power Company, on account of which the widening of the park has shortened the crest of the Horseshoe Falls by 415 feet, leaving in place of the sheet of water, a dark wall of rock stretching out into the gorge. It is strange that this impairment seems already to be almost forgotten except by a few lovers of the great cataract, but on looking at the Canadian Falls from the upper bridge the effect is to reduce the diameter apparently by one fourth (see figure 1).

16. Water taken by Canals.—The Welland and Erie canals divert less than 2,000 cubic feet per second, and, while the Chicago drainage canal takes at present scarcely more than 4,000, its rights extend to 10,000 and they want 14,000. The diversion by the Chicago canal of 10,000 cubic feet produces varying effects in the different basins, but it may be given at a lowering of the lakes by six inches, or some three inches for the basin at the Upper Rapids.

17. Effect of Power Diversion on the Falls.—We are now in a position to determine the effect of power diversion upon Niagara Falls and upon the navigation of the lakes. The water taken from below the