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The Enterprise, White Salmon, WA., June 14, 1912, page 1

BIG DAM EXPENSIVE
Cost Will Reach Well Over half a Million Dollars

A small amount of basalt rock is to be ground into sand for use in the dam which the Northwestern Electric Company is building in the development of its power site on the White Salmon river. The dam, preliminary work for which is now underway at the back of the Kuhne Orchards three miles above White Salmon, Washington, will be 100 feet high, 400 feet long and 100 feet thick at the base, from there tapering to a thickness of 15 feet at the top.
Orders were placed by the Northwestern Electric Co. from its head offices in Portland this week for three rock crushers to grind up the rock. According to the engineer's estimates, 20,000 cubic feet of this material, or 30,000 tons, will be needed in the mixing of the concrete for the dam.
So far as the engineers know, this will be the first time that crushed rock has never been used in place of sand in concrete work of this magnitude, but they say the result will be the strongest dam in the world.
Its resistance to pressure, it is said it, will be enormously increased by substituting the rock for sand. By a series of very careful experiments with samples of the ground-up rock, Columbia River sand and what is known as standard sand, it has been mathematically determined by the engineers that the crushed rock gives the concrete in which it is mixed a tensile strength from 50 to 75 percent stronger than that obtained with the standard sand.
Columbia River sand has a holding power about 15 percent below that of the standard sand.
The reason given for the greater strength of the concrete mixed with crushed rock is said to be that the bits of crushed rock are jagged, not smooth, like grains of river sand. Each little projection on each bit of rock makes its relative holding power that much greater.
The Northwestern Electric engineers originally decided to use the crushed rock instead of sand because of the inaccessibility of the dam site.
All the sand used would have to be hauled in from the Columbia River, three miles distant, and the cost would be exceedingly high. Tho the cost of crushing the rock is heavy, it is estimated that it will prove considerably cheaper than the sand in the long run, besides resulting in a mixture much stronger.
All the rock needed will be taken from a hill at one side of the site of the dam. The rock blasted out of the side of the mountain will be rolled down by gravity to the crushers, ground up, screened and the resulting sand poured down by gravity to wherever it may be needed along the dam. No other handling will be required.
The contract for the dam and power plant calls for its completion by the first of January, 1913. It will develop 20,000 electrical horsepower. High tension copper wires will bring the current to Portland, tho much of it will be used in Washington towns. -- Journal.