The Florence tribune., 1899-05-06
AS TO IRRIGATION.
MT. A. P. Davis of the Hydrosrsphic Sur
 vey in Town.
IFrom the Phoenix Republican,


 Buttes near Florence, arrived at the Commercial yestesday. Mir. Davis was delegated three years ago to make a report of the Buttes as to the feasi- bility of constructing a dam. The preliminary report was made. but at | that time the government could not spare money to continue the explora- tion. By special appropriation the work has been going on since last fall, and the second report will be made the latter part of the summer. l The result is of importance to Flor enee and vicinity If the the water of the Gila is conserved there will be as much land under irrigation as is now watered in this valley and in short time Florence will be one of the thrifty and populous cities of the territory.
 The investigations at the Buttes have been in a slight degree discouraging. It was at first thought that masonry dam could be constructed, but that theory has been exploded. Twenty six holes have been bored and the d eepest, to bedrock, is 123 feet. A diamond drill was employed to sink a short distance farther and it was as- certained that the rock is soft and porous. For this reason the only practical dam would be a rock-flled one. To attempt to construct a mason ry dam to an adequate height on that location would be an innovation in engineering, and it is preferred to be conservative.
 The engineering part has also been experimenting on Queen creek and at Riverside, one-half mile below the mouth of Mineral Creek. Bedrock was struck at seventy-ive feet at River side. The rock is we'll adapted for building dam, but at that place the canyon is about twice as wide as at the Buttes. There is one favorable condition. The canyon is shaped so there would be a natural spillway or outlet for surplus water.
 The streams tributary to the Gila are torren tial and much more silt is carried than in the Salt river. The source of the Salt is in high noun tains bearing vegetation, while the 
 headwaters of the Gila lie in low bar ren mountains where the erosion is greater. The question of disposing of the sediment has some weight in the location of reservoir.
 Whether it would be advisable to conserve the water of the Gila at the Buttes or near Mineral Creek is largely ! a matter of the comparative expense. built large enough to conserve a good supply of water, but is it doubtful if it would not be better to construct dam at both the Buttes and at River side. The alluvial deposit in both reservoirs would make them gradually more shallow. If the two reservoirs are constructed system of sluicing would be established. A heavy dis charge of water from the upper res ervoir would not only remove the deposits from the lower one, but the swift outpour in itself would carry away great amount of sediment.
 If dam should be built across the river at Riverside, the water backed up would destroy agricultural prop erty, but what would cost the govern ment most would be the destruction of mining property. So it is not likely that the government will undertake to establish reservoir at Riverside without first determining exactly what would be the extent of damage done. The report made by Mir. Davis three years ago included m estimate that the cost of constructing dam at the Buttes would be about $2,000, 900, and he thinks it would cost a little more to build masonry dam at River side without including the damage liabilities.
 The party is now operating at a new site on Queen creek. Bedrock WAS found at thirty-seven feet, but the supply of water is scant. The drain age area of the creek is only about 142 square miles, and in that dry section the area is inadequate. At present there is no water in the creek. Other things are favorable for the dam, but on account of the dryness the under taking there will not likely be begun. Mir. Davis said yesterday that while he had met with some Encouragement in his investigations, he did not think the plan for reservoir impractical.
 "It is practical to built one at the Buttes and at Riverside or at both places," he said, land there are the strongest reasons why the Gila water should be conserved. There are three good arguments favoring it, and the same arguments can be applied to few ,.IooaS Firof on ,s