The New Inland Sea 



41 



the waters spread over a large area of 

 the country, and as the quantity increased 

 threatened' to engulf the farms and the 

 town of Calexico. Large dikes were 

 hurriedly built to shut out the water, 

 and the town was thus saved from dis- 

 astrous inundation before the waters 

 rose high enough to sweep it away. In 

 the meantime channels formed near the 

 Salton Sea, and were cutting deeper and 

 deeper, the cataracts therein were ad- 

 vancing upstream as the water under- 

 mined them and carried the debris into 

 the sea. As these cataracts advanced 

 vipstream they left below them, of course, 

 deep channels, which carried all the water 

 far below the surface of the surrounding 

 country to the Salton Sea. In the early 

 part of the present year the cataract in 

 New River had reached Calexico, after 

 which, instead of threatening to overflow 

 this town, the water was in a gorge 45 

 feet below the surrounding country. 

 Opposite Imperial the channel of New 

 River is over 80 feet in depth and that 

 of the Alamo nearly as deep. 



The large amount of water flowing- 

 down the Alamo River was rapidly erod- 

 ing this channel throughout its course. 

 Sharp's Heading is a cheap wooden struc- 

 ture and has been for some time in im- 

 minent danger of washing out, which 

 would have left the canals of Imperial 

 Valley without water for irrigation, 

 though domestic water might have been 

 obtained with great eiTort from the deep 

 channels of the Alam.o and New rivers. 



THE RETREATING CATARACT 



The deep channel in the Alamo River, 

 which passed Holtville in August, was 

 gradually approaching Sharp's Heading, 

 and it was recognized that when this 

 cataract reached the heading it would be 

 very difficult and expensive, and perhaps 

 impossible, to maintain that heading. 

 This, however, was not the only peril to 

 the water supply of the valley. The 

 channel of New River had eroded to 

 such an extent that where the two 

 streams separated it was estimated that 

 four-fifths of the water was runninsr 



down New River and only one-fifth down 

 the Alamo. While this proportion was 

 favorable to the regimen of the Alamo 

 arid the safety of Sharp's Heading, it 

 was very threatening in another respect. 

 It accelerated the cutting of the New 

 River channel, in which was a great 

 cataract four or five miles below the 

 separation of the two streams, and this 

 was, of course, advancing upstream. It 

 was well recognized that when this cata- 

 ract reached the Alamo the channel 

 would be so deep that all of the water 

 would run down New River and leave 

 Sharp's Heading on dry land, without 

 any water for the irrigation of the Im- 

 perial Valley. Threatened first with in- 

 undation, and next with the destruction 

 of their entire water supply, the inhab- 

 itants of the Imperial Valley have nat- 

 urally been almost in a state of panic for 

 several months. 



THE SAFETY OF $100,000,000 IN THE 

 BALANCE 



The continuation of the flow of the 

 Colorado River into the Salton Sea 

 meant the gradual inundation of the 

 entire Imperial Valley. Whether the 

 lake would ever rise high enough to 

 actually flow out through Volcano Lake 

 to the Gulf of California is problemat- 

 ical. Volcano Lake is about 30 feet 

 above sea-level. Taking the mean an- 

 nual discharge of the Colorado River at 

 9,000,000 acre-feet and the evaporation 

 at 6 feet in depth per annum, the lake 

 would fill in 40 to 50 years and would 

 flow a considerable stream perennially 

 into the Gulf of California. But taking 

 the more probable values of 8,000,000 

 acre-feet for the mean annual inflow and 

 7 feet in depth for the mean annual evap- 

 oration, the depression would never fill. 

 It would rise to a point 8 or 10 feet above' 

 sea-level and oscillate above and below 

 this level in accordance with the fluctuat- 

 ing annual discharge of the Colorado 

 River. 



Either result, however, would have 

 been destructive of enormous interests. 

 It would have submerged 150 miles of 



