Arizona republican., 1898-12-10

papers issued by that department, un- der the title, Irrigation Near Phoenix, Arizona MT. Davis also points out that the steep slopes of the mountains are favorable to 3 high percentage of run-off.
 Observations of the flow Of the Salt river, extending over a period of more than ten years, demonstrate that the storage reservoir will be filed by the spring floods ir each year. Competent authorities have expressed the opinion that an adequate supply of water for the needs of the Salt River valley can be furnished by this reservoir.
 ''The real purpose of a storage res .ervoir is to regulate the flow of water needed for use in the dry season-the water which, but for the reservoir, would run to waste in time of flood. Reservoir projects of smaller capacity and with smaller watershed, are sub ject to the difficulty that in years of drOUth it may be impossible to fill the reservoir; and, as no ore can predict a year in advance whether there will be adequate floods in districts having a small watershed, many important res ervOirS are compelled 10 carry over from the end of each year at least half of their capacity, in order to meet a possible deficiency in the coming year. MT Schuyler, one of the highest au thOrities on reservoirs for irrigation il the United States, and who was the en- gineer of the SWeetwater dam in Cali fornia, has expressed the opinion that the proper use of the Sweetwater res ervOir requires that at leass one-half of it's capacity should be reserved to the end of each season for possible usu tIa fOI1Curir7c rTOr+0 reservoir will be larger than my res orvoir now in operation in the United States, and very much larger than any now projected, and, in fact, in the whole world there is at present in op- eration, as we are informed, no reser- Voir of as large capacity as can be readily constructed at this point. IE- medi6tely upon the construction of the reservoir it will be possible 10 supply the valley of the Salt river at exactly tho times the water is needed and in the exact quantity required for irriga- ton. Photographic communication wi,l. the reservoir dam will, if necessary, en- able the manager to keep the canal companies of the valley informed OI tho quantity of water remaining in the reservoir from time to time. while at the same time they keep him informec of their needs.
 ''It has been proved to a demonstra- ton that properly constructed dam at this point, furnished with adequate was,e-way5, will be absolutely safe. l. is necessary that it should be of solid masonry, so as to be practically 8 monolith. By adopting a curved plan the company has, at the expense oI some increase in the amount of mason ry necessary, further assured the safety of the dam, but 1t is proposed that the dam shall be of such dimen- sions and construction as to bo per fectly safe were it straight instead of curved. The waste-ways have been planned to carry the greatest flood ever known in the Salt river and leave @ large margin for the remote pOssi- bility that some flood greater than the famous one of 1891 may occur. But the plans adopted for the dam are such tha5 were the water to overflow it's toD, the dam would not be injured"