Evening star., 1914-07-25


ing works are still to be installed. This
great project, costing many million dol
lars, was constructed through the United
States reclamation service. The oam
constitutes one of the greatest irrigation
reservoirs in the world and is a fne speci-
men of constructive engineer work 1t
forms a great lake covering twenty-five
square miles and holding water enough to
cover a million and quarter acres OF
land q foot deep. The dam structure is
gigantic, composed of stone and concrete.
The farmers benefited by the Roosevelt
dam project have agreed to repay the ex-
penditure within the next ten years.
In addition to the storage Of water the
dam will supply power to the pumping
works as well as
Will Give Power to other indus
l. tries now existing
oped in the future It supplies the city of
Phoenix with its electric light and street
car service. and operates several mills
and other Industrial works. Those who
see far into the future predict that it will
furnish power for cotton factories erected
to utilize the cotton crops which its water
makes possible in the reclaimed desert
This is in the future. however. At pres
ent the dam and its adjuncts are supply
ing ample irrigation to nearly half mil
lion acres Of land much of which was
absolute desert before. That which had
been under cultivation produced only
scanty and undependable crops because
Of the uncertain water supply. The tr-
r1gation service of this dam project is
being supplied to farmers at the rate of
S45 per acre. In addition to this. the sale
of surplus power will bring in an in
creaSing revenue annually.
The entire irrigation project, Of which
the Roosevelt dam Is the most important
feature. comprises the watershed drained
by the Salt and Verde rivers. drainage
plants operated by electric power from
the big dam for the collection of surface
waters which may arise injuriously dur
ing the rainy season. and the Granite reef
diversion dam, at the head of Salt river.
This last will insure the diversion of reg
ular river flow and storage waters to the
irrigated land. Temporary diversion dams
have been constructed before for this pur-
pose, but the high floods following the
rainy season destroyed them and caused
the loss of water which should have been
stored. About four-fifths of the land
covered by this irrigation project is irri-
gated by water stored in the reservoir.
I The balance receives Its supply from
moisture collected from the surface by
pumps with power. supplied by the dam.
The Roosevelt dam is so unique a fea-
ture Of architecture that 1t is becoming
great attraction
Roosevelt Dam to visitors in the
Attracts Visitors. so,,rass sou,n"S" co-.na =
MES exploit 1t and attractive automobile
rides have been arranged around 1t. A
few conservatives claim that the collec-
ton of so enormous "a body of water tends
to produce humidity in the atmosphere.
and that the temperature has been rem
dered more oppressive because Of it.
This is Indignantly denied by the Phoeni-
clans. Scientists also state that such a
claim is not sustained by the meteoro-
logical records.
| The Laguna dam. located near Yuma,
in the extreme southwestern corner Of
voir lately constructed. 1t irrigates the
Yuma valley, in Arizona, and the cele-
| brated Imperial valley, In California.
Both Of these had formerly been noted
| for their extreme heat The new water
supply is fast changing their claim for
distinction from heat to crop production.
| The soil In these valleys is marvelously
fertile. The crops produced are record
breaking In quantity and quality. At the
| celebration held in Yuma at the compile
ton Of the dam prizes were awarded for
no less than forty-three distinct products
of the soil. Each was produced in cred
table quality. They included an alpha
betical list beginning with alfalfa and
| ending with yams, embracing material
providing food. shelter and clothing for
| man and beast. Most Of the crops of the
temperate zone. as well as the fruit from
! the tropics and a superior variety Of cot
| ton, were exhibited.
| Laguna dam Is about 5000 feet long
250 feet wide and twenty feet high. This
broad. low structure raises the minimum
| level Of the water about ten feet, thus
assuring irrigation throughout the dry
season. Its most notable feature is the
gigantic syphon which goes under tho
Colorado river ct Yuma and conveys
| water from 1t into the dam. This syphon
| is SO enormous that a banquet was held
In it last year before the water was
| turned on. The banquet, attended by the
governors Of three states, several great
| English scientists and engineers, as well
as a distinguished company of Ameri-
cans. was a notable event in the cele-
bration ceremonies. The Laguna dam
| project provides for the irrigation of
10000 acres. of which 10000 acres lie
in the Imperial valley of California. The
rest Is in Arizona Tho cost to sub
scribers for this irrigation service is $55
an acre. without interest Other large
areas arc being indirectly benefited by
this water supply. SO the history Of agri-