GEOGRAPHICAL FEATURES OF THE CAHUILLA BASIN. 19 



range, some 7 miles north of Julian. It drains the country to the south and west of the 

 Santa Rosa Mountains and forms a junction with Carrizo Creek in about 33° 6' N. and 

 115° 57' W. Carrizo Creek itself has two forks, one coming from near the international 

 boundary-line, and the other from the south side of the Fish Creek Mountains. The 

 combined creek thus formed runs north to its junction with San Felipe Creek, as above 

 mentioned, and carries on its own name down into the Salton Sink. Here, too, the water- 

 flow is very irregular, long periods of total dryness alternating with occasional heavy 



floods. 



THE CHUCKAWALLA WASH DRAINAGE. 



The only drainage system of any importance which reaches the Salton Sink from the 

 northeast is that known as the Chuckawalla Wash. This is a large but generally dry 

 desert wash, which drains an area of some 250 square miles, beginning with the slopes 

 of the Chuckawalla and Eagle Mountains. It spreads out and is virtually lost in the 

 extensive playas which lie northeast of Durmid, but at times, during some of the heavy 

 and violent rains to which this region is occasionally subjected, a portion of its water may 

 pass on down into the lowest part of the Sink by way of the Salt Slough. 



RECENT HISTORY. 



During the summer of 1890 the water from the Colorado River filled many of the 

 small channels and lagoons toward the southwest, and in 1891 flowed through into the 

 Salton Sink and formed a lake several miles in length. The intervening region was com- 

 paratively little known and its drainage system hardly comprehended at that time, and 

 the appearance of such a large body of water in close proximity to the Southern Pacific 

 Railroad attracted much attention and gave rise to some of the wildest of rumors and 

 hypotheses as to its origin. William Convers, followed by one or two others, succeeded 

 in making the journey by boat from the Colorado to the lake, and so the mystery was solved. 



Mr. H. T. Cory, who has a comprehensive knowledge of the conditions in the Delta 

 of the Colorado, concludes that some flood water has found its way down the channel of 

 New River toward the Salton every year since the inundation of 1891, and cites opinions 

 of old settlers who allege that water came into the Salton in 1840, 1842, 1852, 1859, 1862, 

 and 1867. The mail stage service between Yuma and San Diego was interrupted by the 

 flood of 1862 and a flatboat was used for crossing New River for several weeks in the summer 

 of that year. (Transactions Amer. Soc. Civil Engineers, vol. lxxvi, pp. 1204, 1571.) 



In 1900, a company having been formed for the purpose, work was begun upon the 

 task of connecting and clearing the various channels which formed the natural waterway 

 between the river and the basin; and by the middle of 1901 water was flowing upon the 

 irrigable lands of what has since become known as the Imperial Valley. It had been deemed 

 advisable by the promoters of the scheme to take the water from the river in United States 

 territory, and so the upper section of the canal was cut almost parallel to the river for 

 several miles and with a very low gradient. This circumstance, together with the general 

 unsuitability of the site selected for the head works, caused considerable trouble for two 

 or three years, as more and more water was required to fulfil the demands of the growing 

 communities in the desert; and so various openings were made between the river and the 

 canal in order to furnish a more adequate supply. 



Then in the winter of 1904-05, one of the infrequent winter floods in the Colorado, 

 coincident with a tremendous rush of storm waters from the Gila, found before itself the 

 unprotected head and comparatively steep downward grade of the canal, and at once began 

 to cut and enlarge the channel. The ordinary summer flood of 1905 also poured its water 

 through the opening, and it was soon realized that the outpour had got beyond control. 



Practically the whole of the Colorado was now flowing into the Salton Basin and an- 

 other flood in the following November (1905) made the task of closing the breach seem 



