Arizona republican., 1902-11-15
THE TONT0 RESERVOIR
A Model of It Now on Exhibition at
 Board of Trade Room.


 hoard of trade room real Tonto | reservoir built by the government. on plans drawn under the supervision O. Engineer Arthur P. Davis. It has been placed there for the purpose of showing the people of the Salt river valley just what the government can 6o and what it will do for this peo- pie if they will get a move on them selves and do the fair thing by the government. Seriously the subject of this article is plaster model of the proposed big 1 government dam ct Tonto, showing all | important details. the lower part of the basin, the bridge over the dam the waste gates, the two tunnels cut | through the solid rock as an exit for the stored waters, the gate towers the | electric power house, the canal that ie l to run along the side of the reservoir ! from it's upper end to the dam and emptying over Q dizzy precipice form a mighty mill race of 1900 horsepower for the generation of electricity. This model was made for the geological survey in Washington and the water storage commission as soon as they heard of it ordered a duplicate The | geological commission in it's desire to help along the preliminary work here. | kindly forwarded the original model to Dwight B. Heard for the commission and will itself take the duplicate as soon as it is completed.
 While this model might suggest to a stranger that it was only the work Of some ones ingenious fancy, to those who have followed the water storage question here it is truly a work of art It Is rich in detail and the more one studies it the better it looks and every question asked by the skeptical, for there may be a few of them left in the community. is answered by the model ii the questioner will but study it. MT. Davis who is now here is pre- pairing a placard of explanation which will be placed near it.
 The model is built on a scale of one inch to twenty feet so those who look at 1t may gain a fair idea of the magnitude of this big engineering en- terprise. The dam is to be 21O feet high and the cost of the entire enter prisa is estimated at approximately S2,0O0,0O0 and is to impound S4O,OOO acre feet of water. The water stor- age commission and the engineers are now figuring on plans for building the dam forty feet higher than this model calls for. thereby nearly doubling its capacity and impounding 100000 acre feet of water.
 The dam arches up the stream key stone like so that if nothing gives way the greater the pressure behind it the stronger it will be, if there can be such a thing as varying strength. The method of getting the irrigating water out of the dam nay be new to some. On a level with the river bed and at each end of the dam a tunnel is to be cut into the solid rock and on a gen. tie curve pass around the foundation of the dam at each end, many feet distant from that foundation, however. , the two tunnels emerging from the
 canyon side and emptying into Salt : river again below the power house
 The gates to the tunnels will be oper- , ated from the top of the dam over 20l . feet above and can be raised and low I cred at will. Just below the top of the l dam and at each end of it, crossed by I a bridge of mighty span, is the channel
 provided for the waste or flood waters
 if there ever are any. These channels
 are cut through solid rock, there he ing a monster aoutfnent Of solid rock left standing between each one of them ] vision is made for such emergency as . the food of 1891 and the waste channels
 are large enough to carry that entire { flood. assuming that the reservoir is full when the flood begins, so history will have to do a great deal better l than repeat itself before the water can ever top the dam. These waste chan :. nels, like the tunnels for the irrigating } water, empty into Salt river again fal = below the power house.
 But the unique feature of the whole . enterprise and a feature but few have 9 learned the details of, is the scheme l for development of electric power. 4 l canal will be dug. heading at the upper l end of the reservoir site, capable ot
 carrying the minimum flow of the I river, whether there is impounded r. water at hand or not. This canal will l skirt the reservoir basin along tn, : water level when the basin is full finally passing round one end of the dam in a channel cut in the rock vast, way, some feet down through : a hole in the rock then ou v and over the precipice to tn, power house. The construction of this
 canal will be the first work in carry ing out the big project and a corps O.
 engineers will begin its survey in {;
 few days. This force will be utilized in generating electric power to bt l used in making the necessary cemen :. from materials close at hand. for run : ming all the huge construction machin. : CT ythat will be used in the building : of the dam and in the operation o1
 the headgates, and later when all i; , finished it will be cabled to the valley
 and employed if desired in raising tn, underground supply here for irrigatinG purposes. The beauty of the plan i : that there will always be water powe1 equal to 12CG horsepower, even if there isn't a drop Of water in the reservoir
 JHANTTT.V DRTDE