The entry follows the fight at the lower heading. This piece follows the water once it was through, as the company’s engineer reported it, as the valley’s own historians told it in 1910, and as the Reclamation Service and the Geological Survey measured it. The valley had two kinds of danger that year, and the second was the opposite of the first.
Where the water went
A sheet of water that spreads over a desert floor does not stay a sheet. The Salton basin falls away from the Colorado’s delta at four or five feet to the mile, in silt that dissolves. In 1905 most of what came through the cut went down the old channel of the Alamo, which the company had been using as its main canal, past Sharp’s Heading, where the valley’s canals took their water, and through the waste-gate below it into the Salton Sea; the rest went over the banks and collected in the sloughs to the west and found the New River, a shallow, winding, ill-defined channel that had carried the Colorado’s overflow perhaps five times in sixty years and ran north across the boundary at Calexico. Between the Alamo, the New River and the Hardy, which runs to the Gulf, the flood waters of 1905 were accounted for, the valley’s historians wrote, “and it was not until January, 1906, that any considerable area in the Imperial Valley was overflowed.”
That winter the water rose over the country south of the line and over a large part of the district of Water Company No. 6, west of Calexico. Mexicali, the border town on the Mexican side, “a settlement which had grown as a sort of excrescence on the edge of the Valley,” was threatened; Calexico was being approached; “it appeared to be only a matter of a short time when everything south and west of the Main canal, two miles north of Calexico, would be inundated.” The water stood about four feet deep over the towns’ ground. Cory, who had just become chief engineer, records that the company’s attorney had advised it to build no protective works on the American side and to avoid any act that might be read as an admission of responsibility for damage done in the United States by the Mexican company’s works in Mexico, and that the towns and the railway waited for the company to build levees in spite of its announced intention of doing nothing of the sort. When the situation was realised, about five miles of levee, six feet high at most, was thrown up round the two towns and tied to higher ground; the valley’s book says a mile, six feet high, built by the citizens of Calexico. Spring winds blew for two or three days at a time and raised waves on the sheet of water that made the levee hard to hold.
The summer flood came on top of this. On 27 June 1906 the river at Yuma read 99,200 second-feet, and the break, now half a mile wide, took all of it. About 75,000 second-feet went down the Alamo channel at the peak. The new waste-gate near Sharp’s, built the summer before to pass what the engineers had then thought a great deal of water, took 3,600; Sharp’s and the Encina gates took what the canals below could carry; and the rest, all but about 6,000 second-feet, went over the banks for miles to the south and west. Cory called this “a peculiar and most fortunate coincidence,” and it was the valley’s salvation: had the water stayed in the Alamo, the channel below the waste-gate, which had already cut back so far that the structure stood “figuratively speaking, on stilts,” would have been breached, “and at once cut the water out of every canal.” The overflow gathered in Beltrán’s and Garza’s sloughs and poured into the New River, and the New River spread “for a maximum width of about 10 miles” just south of the line.
Along the Central Main, the canal that fed Imperial, the water rose in the last days of February until it topped the south bank and threatened to go over the north bank and across country to the Alamo; had it done so, “the Town of Imperial would have been most seriously threatened, perhaps destroyed, and the New River and Alamo chasms would have been joined by a third one, about 26 miles long, diagonally across the valley.” The company raised the north bank four feet for three miles; the citizens of Calexico and Mexicali were called out to hold their levees, and the people of Imperial went down to the Central Main. Workmen building El Centro “were called from their bricks and lumber to go to the levees with shovels and sacks.”
The race
What saved the towns was the thing that was destroying the country. The New River, with four hundred feet to fall and nowhere to go but down, had begun to cut. Where the sheet of water converged into a stream it scoured a bed, “At first slight falls or riffles were formed,” Newell wrote; “Later these progressed backward, deepening as the water scoured out the channel which had formed in the soft earth.” The falls walked upstream, “comparable almost to Niagara in their size and in their apparent height, when compared with the broad level plain,” and in the softer beds they walked about a mile in three days; behind each one the lake drained in hours into a gorge a thousand feet wide. The valley’s historians put it plainly. “It became a matter of a race between the cutting-back of the channel and the rise of the flood about their levees.” The citizens and Perry’s men went to the aid of the cutting with dynamite. Cory’s method was to tie eight to sixteen sticks round a cap with eight to twelve inches of waterproof fuse, light it, and toss the bundle into the water, “A little practice and careful observation enabled one to become quite proficient in estimating how far the bundle of dynamite would be washed down stream by the current before the cap exploded the charge.” He doubted afterwards that it had hurried the fall past the towns at all, though it checked the erosion to either side.
“On the night of Saturday, April 1, with a gale blowing and rocking the flood waters until they lapped the very tops of the levees the alarm was sounded and volunteers rushed to the dikes. For three days, in such a wind as seldom has blown in the Valley, these men fought inch by inch and foot by foot against the rising waters. Exhausted and worn, they carried forward the last few hours of the struggle while, a few rods away, volunteers in rocking row boats risked their lives to deposit sacks of giant powder in the channel to hasten its progress. It was nip and tuck between the two forces but the channel won at last, and to the great relief of Calexico the flood waters began to subside, being sucked into the growing gorge and carried down to the sea.”
When the fall reached the towns the cutting ran, Cory wrote, “fairly uniform at 1 ft. per minute.” “The side cutting of the east bank of the wide, deep barranca for several days threatened Calexico, and carried away a considerable part of Mexicali, including the railroad station, brick hotel, and a number of smaller buildings.” The damage was about $15,000 in Calexico and $75,000 in Mexicali. Newell’s photograph of the chasm through Mexicali, with the houses at its lip, is Plate V of his article. Past the towns the cutting followed the borrow pits of the Inter-California Railroad and destroyed it for a mile and then for several miles more. The flood covered about 6,000 acres of farms and ruined the crops; worse followed as the lake drained, when the water rushing from each side toward the new channel cut side canyons back 2,000 feet and more, “It thus happened that about 8 000 acres of improved and 10 000 acres of unimproved land were eroded to such an extent as to be practically ruined for agricultural or any other purposes.” About 7,000 of those acres were public land. The channels themselves took 7,000 acres more. The worst injury was to the two districts west of the New River, Water Companies 6 and 8, whose flumes over the river went down the gorge; about 30,000 acres, 12,000 of them in crop, were left without water and “practically uninhabitable.”
Then the fear reversed. “Cutting back in New river was a means of salvation,” the valley’s book says, “but what if the process should continue back through the Pink Mountain and Garza sloughs, and so to the Alamo River? What if Sharp’s should be left high and dry and the channel should be deepened back through the Alamo to the very intake itself? What if victory should be delayed at the heading until the deepening channel should pass Yuma and attack the foundations of the great Laguna dam, 12 miles above?” Kennan made the arithmetic of it: twelve thousand people whose drinking water came from the canals would have had forty-eight hours to leave. “Paradoxical as it may seem, the danger of being driven out by lack of water was even greater and more immediate than the danger of being drowned out by the rising flood.” Cory judged from the soils that the recession would not get more than six or seven miles past Calexico before the summer flood of 1908, and crews of Indians were sent into the sloughs to spread the water with brush and earth so that it could not concentrate and cut. “This means was successful, but had the fight been an indefinite one the settlers would certainly have lost.”
The sum of it was geological. “In 9 months the runaway waters of the Colorado had eroded from the New and Alamo River channels and carried down into the Salton Sea a yardage almost four times as great as that of the entire Panama Canal. The combined length of the channels cut out was almost 43 miles, the average width being 1 000 ft., and the depth 50 ft. To this total of from 400 000 000 to 450 000 000 cu. yd. must be added almost 10% more for side cañons, surface land erosions, etc. Very rarely, if ever before, has it been possible to see a geological agency effect in a few months a change which usually requires centuries.” The two gorges are the valley’s drains now. Cory counted their creation the diversion’s greatest benefit, because an irrigation company does not build drainage and a valley of mutual water companies cannot agree to, and because “the need for drainage of irrigated land is usually not recognized in time, and not admitted when it is recognized”; the valley’s historians, “even at the risk of being thought unjust and heartless,” said the same, and wished the valley had assessed itself to pay the farmers whose ranches “were swallowed up to benefit the whole community.” It never did.
The sea
At the bottom of the basin the water had nothing to do but rise. The Geological Survey’s gauge, kept by W. B. Clapp, read 273.5 feet below sea level in November 1904, before the cut. The sea rose 0.8 feet in the last two months of 1904, 21.9 feet in 1905 and 49.8 feet in 1906; in June 1906 alone it rose 15.4 feet, nearly seven inches a day, or 16.4 by Cory’s figure. It stood 201 feet below the sea at the end of 1906 and reached its height of 197.4 feet below, by the Survey’s datum, in 1907, after the closing: 76 feet deep at the salt beds, about 445 square miles, fifty miles long and ten to fifteen wide. Then it fell, 0.18 feet net in 1907 and about twenty-two feet by January 1912, laying bare 115 square miles that had been under water, which, against everyone’s expectation, turned out to be farmable.
The salt works went first, early in 1905, and the New Liverpool Salt Company hurried to ship out its stock. Cory valued the plant at about $126,000; the company’s judgment against the development company, in November 1907, was for $458,246.23, with a decree that forbade the company ever again to divert more water than the valley needed, and that was later construed so that the salt company could no longer object to the basin being used as the valley’s sump.
The railway’s main line had been built across the sink in 1876 and dropped to 265 feet below the sea at Salton. The water reached the rails in July 1905. Shooflies 1 to 7 were built at 250 feet below the sea or higher, “nothing very aggressive being attempted because of optimistic advices as to when the river would be under control.” Shoofly 11, thirty-nine miles long, followed the 200-foot contour; it was built in February and March 1906, when the chance of controlling the river before the summer flood seemed to be vanishing, and located to be safe for at least two years by the river’s discharge records; by late October some of it was in trouble, the water being 47.5 feet higher than when the line was surveyed. After the second break, Shoofly 12 was surveyed along the 100-foot contour, 48.9 miles, and graded in January and February 1907; about four miles of track had been laid when the closing made the rest unnecessary. The cost of all this to the railway, exclusive of the last grading, was $724,801.70, and on its branch into the valley, where the track crossing the Alamo north of Brawley was moved five times and the crossing of the New River three, $37,862.80 more; the Inter-California’s losses were $108,245.98; the whole, $870,910.48, without counting interrupted traffic. The newspapers, Newell noted, preferred to print that the ocean had come up through a crack in the earth.
Nobody died in the valley’s flood that anyone recorded. Prospective settlers stayed away. The people who were there mostly stayed, and the valley’s book says that El Centro was being built through the worst of it and that, except for the days when the towns were threatened, “there was little curiosity displayed.” By the summer of 1906 the valley had five newspapers reporting the fight with the river, one of them started as a daily for the purpose, and it was from them that the settlers learned how the heading was going, four miles south of the line and sixty miles away.