Throughout the month of August 1905, the intake continued to widen, with the caving away of its banks, and in September Mr. Harriman and President Randolph decided that another effort must be made either to close the break, or to regulate and control the flow of water through it. About the first of October, at the suggestion and under the supervision of Mr. E. S. Edinger, a Southern Pacific engineer, an attempt was made to close the channel west of the island by means of a six-hundred-foot barrier-dam of piling, brush-mattresses and sandbags. This dam, which was built in October and November at a cost of about $60,000, might perhaps have checked or lessened the flow through the crevasse if nothing unforeseen had happened; but on the 29th-30th of November a tremendous flood, carrying great masses of driftwood, came down the Gila and increased the discharge of the Colorado from 12,000 to 115,000 cubic feet per second. The dam could not withstand such pressure, and even before the peak of the flood was reached it went out altogether, leaving hardly a vestige behind. As a large part of the island was eroded and carried away at the same time, further operations in this locality were regarded as impracticable. The crevasse had then widened to six hundred feet, and nearly the whole of the river poured through it into the deepest part of the Sink, where there was already a lake with a surface area of one hundred and fifty square miles. The main line of the Southern Pacific, in many places, was almost awash, and the whole population of the Valley was alarmed by the prospect of being drowned out. If the break could not be closed and the river brought under control before the period of high water in the spring and summer of 1906, it seemed more than probable that sixty miles of the Southern Pacific track would be submerged; that the irrigation system of the California Development Company would be destroyed; and that the whole basin of the Imperial Valley would ultimately become a fresh-water lake.
The difficulty of dealing with this menacing situation was greatly increased by the necessity of furnishing an uninterrupted supply of water to the farmers of the valley while engineering operations were in progress. It would not do to shut the river out altogether, because that would leave without irrigation nearly two hundred square miles of cultivated land. The Colorado must be controlled, but not wholly excluded. Several methods of solving this problem were suggested, but the only two that seemed likely to succeed were advocated by Consulting Engineer Schuyler and Chief Engineer Rockwood. Mr. Schuyler proposed that a new steel-and-concrete head-gate be put in near Pilot Knob, where a solid rock foundation could be secured; that the four miles of silted channel be re-excavated and enlarged by a powerful steam dredge specially built for the purpose; and that the whole low-water flow of the river be then turned through this head-gate into the enlarged canal and thence into the Alamo barranca west of the break. By this means the settlers would be continuously supplied with water, while the crevasse-opening would be left dry enough to close with a permanent levee or dam. The whole work, it was thought, could be finished in three months, or at least before the coming of the next summer flood.
Chief Engineer Rockwood’s plan also involved the building of a new head-gate, but he proposed to locate it on the northern side of the intake, and to carry the whole low-water flow of the river through it by means of an excavated by-pass. This, too, would keep the settlers supplied with water and leave the crevasse-opening dry while it was being closed. The chief objection to the latter plan was that the head-gate would necessarily be of wood, and would have to stand on a treacherous foundation of easily eroded silt which might possibly be undermined. Late in November, after full consideration, President Randolph decided to try both plans and to work on them simultaneously. Contracts for the structural steel and iron work for the concrete head-gate were let in Los Angeles; the machinery for the 850-ton floating dredge “Delta” was ordered in San Francisco; materials for the Rockwood head-gate were collected on the northern side of the intake, and work was pushed on all of these structures with the greatest possible energy throughout the winter. In spite, however, of all efforts, none of them could be finished in the allotted time. The steel-and-concrete head-gate was not completed until the 28th of June; the dredge “Delta,” owing to the partial destruction of San Francisco, was not ready until the following November, and even the Rockwood gate, on which alternate shifts of men had worked night and day, was not in working order until the 18th of April. Meanwhile, the summer flood of 1906 had begun, with a discharge of 32,200 cubic feet per second through the crevasse. This flow would have exceeded the capacity of the Rockwood gate, even if it had been possible to turn the river through the by-pass that led to it, and the attempt to bring the Colorado under control was again temporarily abandoned.
Lower Intake in Spring of 1906 (showing site of Rockwood head-gate and first three attempts to close the break)
Then a long series of misfortunes and catastrophes followed, one after another. On the 18th of April, 1906, San Francisco was partially destroyed by earthquake and fire, and Mr. Harriman hurried to the scene of the disaster for the purpose of affording help. President Randolph soon joined him there, and, at the first opportunity, described to him the almost desperate state of affairs in the Colorado delta. The California Development Company had used up the $200,000 loaned to it by the Southern Pacific the previous year; the river was still uncontrolled, and the impending flood threatened to inundate the Valley and deprive 12,000 people of their property and homes. Mr. Harriman was not a man to be daunted or “rattled” by a sudden and menacing emergency. “There, in the bustle and confusion of temporary offices, with the ruins of San Francisco still smoking, with the facilities of his roads taxed to the utmost in carrying people away from the stricken city, with the wonderful railway system which constituted his life work crippled to an unknown extent, and with the financial demands resulting from the disaster impossible to determine,” he consented to advance an additional sum of $250,000 for controlling the Colorado River and protecting the Imperial Valley. “It has always seemed to me,” writes Mr. Cory, “that this was really the most remarkable thing in the whole series of extraordinary happenings.”
With the promise of this additional sum of $250,000, President Randolph returned to the Imperial Valley to take up again the fight with the runaway river. The flood, at that time, was steadily rising; the width of the crevasse had increased to a quarter of a mile, and the Colorado was pouring into the Salton basin more than four billion cubic feet of water every twenty four hours.
On the 19th of April, 1906, the day after the San Francisco earthquake, Mr. C. R. Rockwood, who had been the chief engineer of the California Development Company for about four years, tendered his resignation, and Mr. H. T. Cory, President Randolph’s assistant, was appointed in his place. The Southern Pacific Company then assumed full control and direction of defensive operations, and all subsequent work was planned and executed by its engineers, with the powerful support of Mr. Harriman and his great railway system.
Agricultural Sands Eroded and Destroyed by Flood Water