Elmore County Republican. [volume] (Mountain Home, Idaho) 1910-1915, 1912-02-03
DUTY AND MEASUREMENT
OF WATER.

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The greater part Of the land IN
the west would be practically
worthless with water with which
to irrigate it, yet there is far less
attention given to the measureme
of this water than there is to the
measurement Of the land. Under
the Carey act the land is sold to
the settler for so cents er acre
and would hardly be worth that
without the water while water
costs the settler all the way from
$25 to 500 per acre. No one
would think Of buying a farm or
any piece OF property without hay-
ing its boundaries located by the
county surveyor or competent
engineer, yet nine out OF ten r.
rigators accept the water that is
given by the water master without
measurements or question, even
though it is ten times as valuable
as the land to which it is applied.
These conditions should be chang
ed. Every irrigator should install
measuring device in his head
ditch and learn how to measure
water accurately and then see that
he secures whatever he is entitled
to. We have been far too care
less in the past about water meas
urement.
Miner s Underwater was first
used in Idaho and other western
states Tor mining purposes, the
common method of measurement
being called the miners inch
method. The miners inch was the
unit upon which such measurement
was based, being the amount Of
water that flows through a sharp
edged orifice one inch square I'M
der a given pressure. The guam
tity called for by miners inch
however, varied in different states
due to the fact that the pressure
over the orifice was not the same.
The Idaho statute called for a
pressure Of 4 inches over the CEN
ter Of the orifice while in Mon
tana the law called for a 6-inch
pressure. This variation resulted
in no end of confusion and as the
miners inch was not adapted to
the measurement of large streams
its use has been discontinued for
a cubic foot per second.
The cubic foot per second
which represents a definite tan
glble amount that is easily under
stood, was adopted as the legal
standard for the measurement of
water by the Idaho legislature in
1899. 1t is commonly known as
the second foot" and represents
the flow OF water which will ex-
actly fill vessel containing one
cubic foot each second of time
Tor as long a period as it is al
lowed to flow. Hence, a flow of
one cubic foot per second deliver
90 cubic feet per minute, or 5000
cubic feet per hour,or $4,000 cubic
feet in a day Of "a hours.
1t is found that one cubic foot
per second equals flow of al
most exactly so Idaho miner s
inches, or $50 gallons per minute.
A flume one foot wide and one
foot deep, if filled with water
that is flowing at the rate of ex-
actly one foot per second, will car
ny one cubic foot per second, and
other fumes or bitches in the same
proportion. The quantity dischar-
ged depends upon both the velo-
city of the flow and the area of
cross section of the advancing
stream of water. These two fac
tors are taken into consideration
when determining the flow of
large streams and canals, it be-
Ing only necessary to determine
the area of the cross section and
the velocity, with which two
amounts multiplied together gives
the discharge. The cross section
is found by multiplying the aver
age depth OF the stream by the
width. The average velocity is
found by measuring the rate of the
same either with floats or with
a current meter especially con-
structed for the purpose. A close
approximation Of the velocity can
be secured by noting the time
that is required for surface float
to advance through 100 or more
lineal feet of the ditch. This
givse the surface velocity and to
find the average velocity one must
eight-tenths, since the average
velocity is that much slower than