Arizona republican. [volume] (Phoenix, Ariz.) 1890-1930, 1902-04-27

l5aSi1 reservoir SilE- 1t VIII ~ i'Nii4N'
to be very interesting as well as edu-
cational reading:
Salt river. though nolninally tribu-
tary of the ella, really brings far more
water to their junction than does the
Gfla. Though ii drains a smaller area.
its basin is much higher and cooler and
receives an average precipitation far
beyond that of the ella BASIN
The drainage basin of Salt river ana
its divisions is about as follows:
So. miles
Salt river at its mouth. L. $50
Salt river al Arizona dam. eco
Verde river near its mouth 5000
Salt river above mouth of Verde. $3.50
Salt river at dam site below Tonic
creek ........ Observation-Disclosures 9,t9o
Salt river between mouth of
Verde and Tonic dam site.---... 904
The elevation at the mouth is about
1000 feet, while some OF the peaks at
its headwaters exceed 10000 feet in al
titude: the highest. Thomas peak, be
ing given at II, 1856 feet.
In a previous publication it vas
pointed out that Salt river basin w2s
blessed with rather peculiar conditions
favoring a large water supply relative
TO it's drainage area, as follows:
THE southern portion of the territory
may be subdivided into two portions,
that draining directly into the Colorado
and living to the westward of Prescott
and the greater portion to the south
and east. which forms the great ella
river system. The Colorado plateau
is partly of igneous origin, and a great
portion of it is somewhat pervious TO
water Its northern slope for a con-
siderable distance from the summit is
very gentle. and though the precipita-
ton is greater than in most portions of
the territory it is very meagerly
marked by drainage lines and almost
destitute Of water. Sharply contrasted
with these facts are the conditions on
the southern slope. Here, through
most of it's course the plateau drops OF
with a very steep slope which is deeply
cut with drainage lines in which are
living creeks and rivulets OF clear,
beautiful water. such as San Francisco
river, Black creek, White river, Car
rizo creek, Cibicu creek, Box creek,
Cherry creek. Tonic creek. Wild Rye
creek, East Verde river, Pine creek
Fossil creek. Clear creek, Beaver creaE.
etc.
The region OF high altitude, as oe-
fore remarked. lies largely north of the
divide, while the great bulk of the
water flowing from the plateau. as
proved both by erosion of drama e
lines and by the volume of permanent
streams, flows away to the south. This
explana ton of this is partly the poros-
ity OF the strata composing the plateau
which allows the water to sink instead
of flowing OF the surface. Once un-
derground. its egress to the south /:
1
it must perColate on a given grade be
fore reaching a surface, due TO The
more abrupt slope.
Another partial explanation is fount
in the meteorological condition. TIT
moisture OF this region is brought from
the Pacific ocean and the Gulf of Cali
fornia by the prevailing southwes
wind. AS this wind ascends the eleva
lions toward the Colorado plateau, it!
temperature is lowered, which reduce.
its capacity for holding moisture lnC
increases its relative humidity. Whal
this quantity reaches 100 per cent il
any any part, precipitation occurs
This influence continues until the vino
passes the summit where the process i
reversed
PHOTOGRAPHIC RESOURCES.
photographic resources of the countr.
Immediately southwest of the Colorad
plateau are disproportionateIy grea
when compared with those to IN
northward. For instance, the preci2i
tation at Fort Apache, as shown by
mean of 20 years observations, is 49,
inches, the elevation being $3.50 feet
while the precipitation at Holbrook, {.
an elevation CT 5,047 feet, on the north
ern slope. is SAT inches as indicated b,
the mean of ten years observations
This is an important fact, especial,
when taken in connection with the fac
that the great areas OF valley land witt
a semi-tropic climate lie in the south
western portion of the territory. IN,
are easily covered by the stream
which are formed by the condition
above described, and which corstitut
the main features of the great Gil;
river system.
The topography of the basin of Sal
river proper above the mouth of III
Verde, is nearly all of a rough. noun
famous character. The chief tributal.
above this point is Tonic creek. an
about half a mile below its juncti0
with Salt river, the latter enters d pro
found canyon with precipitous side
anu HdtICN DCJtOih, IN winch Is locate
the proposed dam site. The Salt m
TortO both occupy comparatively ope
valleys above this gorge. and have
moderate fall. The combined effect
one of the most capacious reservoirs i
the west. The dam might be built 1
a height of 300 feet OF more if such
height were justified by the water sun
ply. The capacity Of the reservoir Wa
determined by planetable survey 80
each 10-fo0t contour to height OF u
feet above the bed of the river in In
gorge. These capacities are given :
the following table:
SALT RIN EIt RESERVOIR.
Height above Capacity of Tota
low water. Area. Section. CapacIt
Feet Acres Acre-ft. Acre-f
10 a 100 12O