Arizona republican., 1911-03-19
BUILDING IF
 THE B|G DAM Magnitude of the Work
 Told in Figures STATISTICAL INFORMATION
Events of Development in the Order of Sequence; Auxiliary Features and Their Relation to the Undertaking

The Roosevelt dam. situated half mile below the confluence of Tonto
 creek and upper Salt river. at the
 head of a canyon through which Salt
 river flows for many miles. is the most imposing feature of the Salt river project. the first one undertaken by the United States reclamation service under the provisions of the
 reclamation act approved by Presi- dent Theodore Roosevelt June r.
 1902. and after whom the town at the dam site is named. It is seventy-siX
 miles east of Phoenix. which is situ- ated in the center of a fertile valley. of which the greater portion, or 240,- O00 acres, is signed to the Salt River Valley Water Users association. This corpora ton represents the farmers in their dealings with the government guaranteeing payment of the con- struction cost of the project.
 The dam creates a reservoir eS- tending twelve miles up Tonto creek and thirteen miles up Salt river nearly to what is known as the In take dam. 100 feet long. referred to later The capacity of the reservoir is l,2S4 .205 acre-feet. the largest arti- ficiai lake in the world. Though the dam is not the largest in the world. it is among the largest. The foundation rests on bedrock. forty feet below datum on river level It is 235 feet long. between the canyon walls and l70 feet wide From the river level to the crest of the spillways at either end of the dam the height is 220 feet, .. eyfs. age possible The spillways are bridged. and over the bridges and the top of the dam runs the only highway in that region connecting the mountain country on the north and south sides of Salt river This roadway is twenty feet above the highest storage, and coping four feet high protects the roadway. From the bottom of the foundation to the top stone of the coping is 2S4 feet.
 The dam is curved, arching up- stream, and at the top is 6SO feet long land l6 feet wide. The spillways at either end are 200 feet wide. so the length, inclusive of the bridges over the spillways. is 10sO feet The ! spillways are blasted from the moun- | tain sides and the bridges over them | angle q little upstream from the | ends of the dam.
 The dam contains 339.4OO cubic | wards of masonry. every stone of ! which was washed before it was per manently cemented in place. In the | construction of the dam and auxiliary | works 33S.452 barrels of cement were ! used, all manufactured on the ground | d a cost of s1.063,542 36. in d cement | mill erected by the government and I recently sold. The cost was s314 per barrel. as against s4S9 per bar | rel. the best private bid available | when operations began. The manu | fracture of cement on the ground ef- I fected a saving of S5s2 300, or s25O | per acre for each acre signed to the | Water Users association
 The dam was constructed by John l NJ. O'Rourke & Co. of Galveston. Texas. to whom the contract was awarded April s. 1905. The award | was at given prices per yard on diff fering classes of work, with d time limit of two years for completion to an elevation of 15O feet Provision was made for time extensions in the event of unpreparedness on the part bl Aiit kON t4 di dbA SAdSt. anu cash penalizing of the contractor for failures on his part. Under the bid the estimated total cost of the con tractors work was s1.147,600. There were some changes of plan, some penalties and some time extensions. and the dam being but one feature of an immense project, its total cost as segregated from the rest of it. is not vet available. The first stone was laid in the foundation September 20, 1906. The last stone was laid on the coping 2S4 feet above. February 6. 1911. The upper face of the dam is almost perpendicular The lower face retreats like the pyramids in huge stone steps from the width of l70 feet in the foundation to 16 feet at the top.