management of the California Development Company, they had no intention
of assuming its responsibilities, directing its engineering work, or
deriving revenue from its operations. All they aimed to do was to
see that the money loaned was honestly and judiciously spent. The
financial management of the company, had not previously been above
criticism, to say the least; and Mr. Harriman was fully justified in
taking such control as might be necessary to ensure proper expenditure
of the funds that the Southern Pacific Company furnished. From the
representations made by the Development Company at that time, it was
thought that the lower Mexican intake might be closed at a cost of not
more than $20,000, and the Company proposed to use the remainder of the
$200,000 loan in “completing and perfecting its canal system,” under
the direction of its own technical experts. When, however, President
Randolph made a personal investigation of the state of affairs, shortly
after his appointment, he found the situation much more serious than
the Development Company had represented it to be, and telegraphed Mr.
Harriman that the Imperial Valley could not be saved by the expenditure
of $200,000. To control the river, he said, under the conditions then
existing, would be extremely difficult. Nobody could foresee what would
be the ultimate cost of the engineering operations, but it “might
easily run into three quarters of a million dollars.”
Mr. Harriman could have insisted, even then, upon a return of the
unspent loan, and could have withdrawn from the financially hazardous
undertaking; but instead of doing this, he telegraphed President
Randolph: “Are you certain you can put the river back into the old
channel?” Mr. Randolph replied: “I am certain that it can be done.”
Then wired Mr. Harriman: “Go ahead and do it.”
As Chief Engineer Rockwood was thought to be familiar with the problem
of river control, and quite competent to deal with it, he was allowed,
at first, to take such measures for closing the intake as seemed to
him best. He had made the cutting long before the Southern Pacific
had anything to do with the irrigation of the Valley, and upon him,
primarily, devolved the responsibility of averting consequences that
might be disastrous.
Although the Mexican cutting, at that time, had virtually become a
crevasse, the flow through it was not great enough to endanger the
cultivated lands of the valley. The excess of water overflowed the
banks of the canal--the old Alamo barranca--but it ran into the deepest
part of the Sink, where it slowly accumulated without flooding anything
except the works of the New Liverpool Salt Company. Civil Engineer C.
E. Grunsky, of the U. S. Reclamation Service, who made an inspection
of the intake three days after the loan to the California Development
Company, described the situation as “not serious, but sufficiently
alarming to require some attention.” The most disquieting feature of it
was the steepness of the incline toward the Imperial Valley as compared
with that toward the Gulf of California. The fall of the Colorado from
the intake to the Gulf was only one hundred feet, while that from the
intake to the bottom of the Valley was nearly four hundred feet. As
the distance was about the same, either way, the Valley incline was
approximately four times as steep as the riverbed incline, and if the
whole stream should break through the intake and go down the steeper
slope, the velocity of the current would make the stopping of it
extremely difficult, if not absolutely impossible. When a turbulent
river, in flood, discharges at the rate of 100,000 cubic feet per
second down an easily eroded and comparatively steep declivity into an
immense basin four hundred feet deep, it soon gets beyond control.
The difficulty of dealing with these conditions was greatly increased
by the impossibility of predicting or anticipating floods. The annual
rise of the Colorado, above its junction with the Gila, begins in the
spring, reaches its maximum in July, and subsides to normal about the
middle of August. This period of high water is fairly regular and may
be counted upon. Floods in the drainage basin of the Gila, however,
are capricious, occur at all seasons of the year, and are particularly
violent in the fall and winter months. “These floods,” as Mr. Cory
says, “are far more to be feared and reckoned with, in preparing and
conducting engineering work along the lower Colorado River, than
anything coming down the Colorado River proper,” partly because they
come suddenly and unexpectedly, and partly because they carry immense
quantities of driftwood. During the Gila flood of November 29-30, 1905,
the water at Yuma rose ten feet in ten hours, with a maximum discharge
of 102,000 cubic feet per second, while driftwood almost completely
covered the water surface. Such floods, coming with little or no
warning, are almost irresistible.
When, in July 1905, the summer flood in the Colorado began to subside,
Chief Engineer Rockwood determined to fend off the main current, and
lessen the pressure on the crevasse, by means of a jetty. Just opposite
the intake was a bush-overgrown island, five eighths of a mile long
by a quarter of a mile wide, which split the river into two channels.
Across the western channel, from the head of the island to the bank,
a semi-barrier was built, of piling, barbed wire and brush. This
obstruction, it was thought, might check the flow into the western
channel, cause a deposit of heavy silt, and eventually create a bar
which would deflect the main current around the northern end of the
island and thus carry it away from the mouth of the crevasse. The
attempt was only partly successful. A bar was formed, but it did not
completely close the channel, nor deflect the main current. There was
still an opening, about one hundred and twenty five feet in width,
through which the rush of water was so great that it could not be
controlled. The attempt to deflect the main current into the eastern
channel, by means of a jetty, was then abandoned.
Up to this time, the Southern Pacific Company had not taken part
directly in the work of river control. After the failure of the jetty,
however, in August 1905, President Randolph sent his assistant, Mr.
H. T. Cory,[11] to the scene of operations, with instructions to
confer with Chief Engineer Rockwood and ascertain what his views
and intentions were. Mr. Rockwood, at that time, did not regard the
situation as at all alarming. The flow through the crevasse, he said,
was doing useful work in scouring out and deepening the main canal
(the old Alamo barranca) and there was little danger that the whole
river would go that way. He was not in favor of closing the enlarged
intake altogether, because that would shut off the water supply of
the Imperial Valley and cause more damage than was then being done by
the river. The deeper part of the Salton Sink, he said, was a natural
drainage basin, and as it was much below the zone of cultivation in the
valley as a whole, the accumulation of water in it was not likely to do
a great amount of damage.
“I told him,” Mr. Cory says, “that I thought the situation was
serious, even granting all he said were true; that he would better
shut the break right away, for while the water might be doing good
work in enlarging the canal of the California Development Company, the
situation was dangerous; that it was playing with fire.”
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.
[Illustration: 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.
[Illustration: Agricultural Sands Eroded and Destroyed by Flood Water]
The task set before Messrs. Randolph, Cory, Hind and Clarke was one
that might well have daunted even engineers of their great ability and
experience. As the summer flood approached its maximum, in the latter
part of June, the crevasse widened to more than half a mile, and the
whole river, rushing through the break, spread out over an area eight
or ten miles in width, and then, collecting in separate streams as it
ran down the slope of the basin, discharged at last into the Salton
Sea through the flooded channel of the New River barranca. Thousands
of acres of land, covered with growing crops, were inundated, and
thousands of acres more were so eroded and furrowed by the torrential
streams that they never could be cultivated again. The works of the
New Liverpool Salt Company were buried under sixty feet of water; the
towns of Calexico and Mexicali were partially destroyed, and in many
places the tracks of the Inter-California Railroad (a branch of the
Southern Pacific) and the Holtville Interurban were deeply submerged
or wholly carried away. The wooden flumes which carried the irrigating
water over the New River barranca were swept down into the Salton Sea,
and 30,000 acres of cultivated land in the western part of the Valley
became dry, barren and uninhabitable. At the height of the flood, the
Colorado discharged through the crevasse more than 75,000 cubic feet of
water per second, or six billion cubic feet every twenty four hours,
while the Salton Sea, into which this immense volume of water was
poured, rose at the rate of seven inches per day over an area of four
hundred square miles. The main line of the Southern Pacific was soon
inundated, and five times in the course of the summer the company had
to move its track to higher ground.
[Illustration: A Flood Waterfall in Imperial Valley, Cutting Back]
[Illustration: Nearer View of Flood Cataract in Imperial Valley,
Cutting Back]
The most dangerous and alarming feature of the situation was the
“cutting back” of the torrents into which the flood-water collected as
it rushed down the delta slope toward the Salton Sea. The fine silt
of which the soil was composed washed out like powdered sugar, and
wherever there happened to be a strong current, the flow soon produced
a miniature rapid. The rapid then became a cascade, the cascade grew
into a fall, and the fall finally developed into a roaring cataract,
which “cut back,” upstream, at the rate sometimes of four thousand feet
a day, widening as it receded, and leaving below it a deep gorge with
almost perpendicular walls. Some of the gorges eroded in the light
friable silt by these receding waterfalls were fifty to eighty feet
deep and more than a thousand feet across. It was estimated that the
channels thus formed during the floods of 1906 had an aggregate length
of more than forty miles, and that the solid matter scoured out of them
and carried down into the Salton Sea was nearly four times as great as
the whole amount excavated in the digging of the Panama Canal. But the
damage actually done by these receding waterfalls was unimportant in
comparison with the damage that they threatened to do. If one of them
should “cut back” far enough to break into the irrigation system of the
California Development Company, all the water in the latter’s canals
and ditches would instantly flow down into the deep gorge below the
cataract, and bring about a disaster almost unprecedented in history.
The twelve thousand settlers in the desert oasis were wholly dependent
upon the irrigation system for their supply of drinking water, and if
that supply should be cut off, they would be compelled by thirst either
to camp around the margin of the Salton Sea, which was ten or fifteen
miles away from most of them, or else get out of the valley within
forty eight hours in a wild precipitate stampede. 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.
The changes in the topography of the Colorado delta brought about by
the crevasse and the floods of 1906 were greater than any that had
occurred there in the three preceding centuries of recorded history. In
referring to them Mr. Cory says:
“The effect of this flood, in a geological way, was of extraordinary
interest and very spectacular. In nine 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 forty three miles, the average width
being one thousand feet and the depth fifty feet. To this total of
400,000,000 to 450,000,000 cubic yards must be added almost ten per
cent for side cañons, surface 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.”
[Illustration: Channel Cut by the Runaway River on Its Way to the
Salton Sea]
FOOTNOTES:
[9] The sill of the Chaffey gate proved to be too high for low stages
of water, and a canal, at a lower level, was cut around the structure
and closed every year with a brush-and-earth dam before the approach of
the summer flood. G. K.
[10] Mr. Randolph was a distinguished civil engineer and railroad
manager, who had been, at one time, superintendent of the Tucson
division of the Southern Pacific under Mr. C. P. Huntington. After the
latter’s death, he went to Los Angeles, where he built and managed Mr.
H. E. Huntington’s interurban system of electric railways and where he
made the acquaintance of Mr. Harriman. Finding that his health would
not permit him to live in the climate of Los Angeles, he returned
in 1904 to Arizona, where he was appointed president of the Arizona
Eastern Railroad Company and the Southern Pacific Railroad Company of
Mexico--Harriman lines. Mr. Randolph, at that time, was regarded as
one of the ablest civil engineers in the United States, and he had
already had much experience in dealing with river-control problems in
the South. He was also one of Mr. Harriman’s most trusted counsellors,
and it was upon his recommendation that the Southern Pacific Company’s
lines were extended into Mexico.
[11] Mr. Cory was a talented civil engineer who had left his
professorial chair in the engineering department of the University
of Cincinnati to enter the service of the Southern Pacific Railroad
system. Just prior to this time--in May 1905--he had been appointed
assistant to President Randolph, with headquarters at Tucson.
THE SAVING OF THE VALLEY
When the Southern Pacific engineers undertook to avert the peril that
menaced the Imperial Valley in the summer of 1906, they found little
in recorded history to help or guide them. Inundations, of course, had
often occurred before, on the Mississippi River and its tributaries, in
the valley of “China’s Sorrow,” and in many other parts of the world;
but these floods were merely overflows on a relatively flat surface.
The cosmical plunge of a great river into the dried-up basin of an
ancient sea was an unprecedented phenomenon, and one which raised
engineering problems that were wholly new. Nobody had ever before tried
to control a rush of 360,000,000 cubic feet of water per hour, down a
four-hundred-foot slope of easily eroded silt, into a basin big enough
to hold Long Island Sound. There was nothing in the past experience of
the world that could suggest a practicable method of dealing with such
conditions. Neither was much help to be obtained from the advice of
hydraulic experts. Of the forty or fifty eminent engineers who visited
the Colorado delta in 1905 and 1906, hardly any two agreed upon a
definite plan of defensive work, while almost everyone found something
objectionable in the measures suggested by others. All admitted,
however, that “the situation was a desperate one;” that it was “without
engineering parallel;” and that “there seemed to be only a fighting
chance of controlling the river.”
Mr. Harriman, who believed and who once said that “nothing is
impossible,” never doubted that the control of the Colorado River was
within human power and human resources. In building the Lucin cut-off
across the Great Salt Lake of Utah he had successfully carried through
one “impossible” enterprise, and he did not hesitate to undertake
another. Inspired by his invincible courage, President Randolph and his
engineers set about their herculean task.