2OO 



THE IRRIGATION AGE. 



only where a foundation of bedrock forces the water 

 to the surface. The diversion of this underflow has 

 not yet been accomplished, though in several local- 

 ities parties are working at it. There seems no rea- 

 son to doubt that at slightly greater expense than has 

 attended the diversion of surface water from the 

 streams, the underflow might be had with a result of 

 adding nearly, if not quite, as much as the present 

 permanent supply, outside the Colorado river. The 

 grade of the rivers is quite favorable to a develop- 

 ment of this source of supply. 



ARTESIAN WELLS. 



Artesian water has been found at Fort McDowell, 

 in the Sulphur Spring valley and near Final. Many 

 wells which do not furnish flowing water have been 

 used with pumps, and in many cases water is in suffi- 

 cient volume to supply enough for large irrigation 

 works. This is notably the case in the Phoenix City 

 water-works, all the water necessary being pumped 

 from one well without nearly reaching its capacity. 



IV. THE COLORADO RIVER. 



This great waterway, rising in the Wind River range 

 of northern Wyoming, intermingling its sources with 

 the Missouri and Columbia and draining a large part 

 of the western slopes of the Rocky mountains in 

 Wyoming and Colorado, courses through the most 

 magnificent canyon of the known world in northern 

 Arizona, and runs through a long stretch of valley 

 along the line of Arizona and California, forming the 

 boundary line for about 200 miles. 



From the southern boundary of California to the 

 Gulf of California, a distance of about eighty miles, 

 lies a region formed by the wash of silt from the Col- 

 orado river making an alluvial plain partly in Cali- 

 fornia and Lower California, and a smaller amount in 

 Arizona. Various plans for irrigation works to cover 

 this delta region are being pushed, notably the Colo- 

 rado River Irrigation Company. The use of the 

 waters of the Colorado and development of the lands 

 in its delta presents some interesting international 

 features of irrigation. It would seem that the topo- 

 graphy of the Colorado river valley is such that water 

 must be taken out at a point some miles above Yuma 

 on the line of California and Arizona for irrigation of 

 the great delta plain. The line of canal will run 

 through California on the west bank of the Colorado, 

 passing into Mexican Territory and thence northward 

 into California to cover a large area of rich land, 

 formerly delta region but now a typical desert and 

 much of it lying below the sea level. This is known 

 as the Salton basin. 



The points most apparent will be, first, the rights 

 of California and Arizona to the water of the Colo- 

 rado, since each may use and need water for irriga- 

 tion. Next the exact definition of rights between the 



United States and the Republic of Mexico as to the 

 ownership and distribution of the water on the Cali- 

 fornia side of the river, since but little can be used 

 until it has passed into Mexico, when a very large 

 extent of ground may be irrigated, but without the 

 protection of a treaty but little might return to the 

 United States from whence it was taken. 



This would not be the case on the Arizona sice, as 

 all use possible would be made before going into for- 

 eign territory. After entering Mexican lands the 

 river reaches so low a level and the channel becomes 

 of such character that it is very probable that no suc- 

 cessful diversion within reasonable cost could be 

 made. It would seem in a treaty covering these 

 points that the United States might reasonably ask 

 for a port on the Gulf of California for the benefit of 

 the region between the coast range of California and 

 the continental divide of western New Mexico, 

 thereby promoting trade between the northern and 

 western States of Mexico and the great region which 

 will develop by irrigation on the watershed of the 

 Colorado. Above Yuma and below the Grand Canyon 

 there have been several small efforts to irrigate both 

 by gravity and by pumping with indifferent results. 

 , Several rich districts of placer mining ground con- 

 tiguous to the Colorado will help establish the devel- 

 opment of water that may later be used for irrigation. 



From Yuma southward, the Colorado has its chan- 

 nel in an alluvial plain, which towards the north and 

 west is much lower than the high water mark of the 

 river. Of course, during extreme freshets, large 

 lakes are formed, and a few years ago, the flood 

 water went over the. barriers and poured down into 

 Salton basin. Sufficient evidences remain to show 

 that at a comparatively recent period, this region 

 was filled with water, perhaps several times. It is of 

 very great interest, since a change is within reach of 

 easy probability, to consider what the effect on the 

 climate of Arizona and eastern California would be 

 if the Colorado river water should become perma- 

 nently diverted to this basin. This would form a 

 lake about 100 miles long and from 20 to 40 miles 

 wide, taking the place of an almost totally dry region 

 of very great heat. It seems probable that it would 

 modify the climate of the lower part of the Colorado 

 watershed, affecting almost the whole of Arizona. 

 As there are evidences of the presence of water to 

 the extent of a large lake quite recently, a condition 

 supported by the traditions of the Indians now resi- 

 dent in that vicinity, may it not be supposed that the 

 prehistoric cultivators of Arizona owed much of their 

 acreage to the greater rainfall and more abundant 

 supply of water in the rivers thereto, and, finally that 

 when the Salton lake dried up, the lessened amount 

 of rain falling in Arizona weakened, and ultimately 

 caused their extinction. 



