Arizona republican., 1922-02-01

against the weight of all water
brought to bear against IT.
Thrust Is Downward
But the multiple arch type is SO
constructed that an increasing weight
Of water tends to tighten and nolo
down the very foundation of the Dam
| and keep the entire structure IN place;
| A series of arches, with faces curved
| outward on the water side, transfer
/ the weight of the water to the put
! tress, which in turn carries the Weight
right down to the foundations SO tnaC
/ the structure is called upon to resist
q downward rather than a horizontal
thrust.
This throws much of the response
bility Of the dam upon the founda-
ton. Specifications for the cave
creek dam call for cemented GraVel
and solid rock foupdation.
The cave creek dam will be 1,IOO
feet long on the crest and "a teet
high. (This height may be changed
slightly.) The structure will conslst
of 3s spans, each of "A feet. All
arches and counterports of buttresses
viii be heavily reinforced with steef
rods,
The dam will store $4,000 acre feet
of water. considered by engineers 10
be of sufficient capacity to care fof
considerably more water than VIII
flow into the reservoir from any one
big rain. Instead of a spillway, tne
dam will be provided with outle'
gates. There will be a separate spill
way about a mile east of the dam.
BY means Of the outlet gates .
filled reservoir may be gradually re-
lieved without causing damage 10 the
/. lands under it.
With the Cave creek dam Mr.. East
wood will have five dams OF ms ue
, sign being constructed slmultane'
ously. The Sespe Light and Power
! company has contracted for three
: multiple arch dams to be built II
: Ventura county, Calf, and I'M
Grandi Consolidated Mining compan!
has contracted for similar dam a
j Anyox. British Columbia. All thes'
y dams are to be built this year.
Mr.. Eastwood designed and super
vised the building OF the world s hrs hrs
concrete multiple le-arch dam IN iSo
at Hume, Calf. Since then ne ma
added Is others to the list' aVefasln'
4 one year.
One Dam a Year
i The Bear valley dam, near Red
lands. Calf, followed the flrst one
being finished IN 1911 ana now So.
4 ING water for irrigation and domesti
supply. Then came the Los Ver]el
| dam. Butte county, Calf, in 1873 i
. In the same years were added Tn
Kennedy and Argonaut dams, nea
Jackson, Calf. -
In 1915-16 the Mountain Dell daI
was built to store domestic water ~
salt Lake City, Utah. Then folloWe
the Malad dam, at Malad, ldaho, i
1915 and a year later the Murra
dam. six miles east of San Diego, no'
storing water for East San Dlego an
a section of San Diego
The Murray dam proved so sue
cessfuI that three more were cor
tracted for in the same vicinity. IN
lake Hotges, San Dieguito an
Eagle's Nest dams were all punt
the vicinity of San Diego during IN
year 1918.
There is now under construction
Carey. Idaho, the greatets OF al iltli
tinle-arch dams to supply water ~ -
the Carey irrigation project. IN
dam will be 2,170 feet long ana L.
a feet high. rro+
y Mr.. Eastwood is now at the Hot
Adams and intends to remain IN u
citv until after he has conferred WIZ
Tvnn 6. Atkinson, Jr., contractor Il !.
). the Cave Creek dam, and with OIL
cials interested in its construction.
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Large share of the labor on SCI
bian farms is performed oy u