The river press. [volume] (Fort Benton, Mont.) 1880-current, 1905-04-12
WEDNESDAY, APRIL II, 1906.
MONTANA WATER MEASUREMENTS

Some interesting information re
garding the measurement of water i.
given in a circular prepared by T. E
Lowery, who represents a firm en-
gagged in the manufacture of irriga tior
machinery. 1t gives definitions of the
several terms used in describing the
volume of water used for various pur.
poses, those in general use being en-
planned as follows:
Cubic foot per second--The stan.
dard unit for flowing water in Mon.
tana, as we'll as in mos: of the
western states and territories, is a
sOlid or cubic foot of water, moving
at the rate of a linear foot in one sec.
ond OF time. Each foot in length of a
hume one foot wide and one foot high
inside measurement, and flowing full
OF water, would contain a solid or Gu.
bic foot Of water. Now If this f1ume
were placed on such grade that the av.
erage rate of flow of water within it
would be just one foot of distance for
each second of time, it would carry a
volume equal to the stand ard unit.
This unit is often abbreviated into the
two words second foot. There are rs
gallons in each cubic foot.
Montana Miners Inch.--Like the
bushel measure for grain, this water
measurement has been abandoned. l
do not know of any Montana farmer
who now measures his grain by means
OF a bushel measure, and yet the large
majority indicate their yields in bu.
shells per acre. Scales of all kinds
have now become SO common that the
old fashioned measure of our grand
fathers time is no longer used. There
have been like changes in the devices
used to measure water, and while we
still retain the term miners inch we
seldom ascertain the flow by the
miners inch box. For small streams
OF water such as are applied to Or
chard and garden tracts the miners
inch Is a convenient unit, and there
are advantages In continuing its use.
In adopting a new stands ard the mem.
bers of our state Legislature foresa w
the extended use Of the old unit and
SO defined 1t In accurate terms. Forty
i40) Montana miners inches are about
the exact equivalent of one cubic foot
per second. An irrigation stream
containing 80 miners inches would be
described as two second.fee by the
new standard, one containing 12O
miners inches as three second.feet,
and SO on. Twelve gallons per minute
is equal to n miners inch.
Acre oot.-The second foot and the
miners inch can only be used for wa.
ter in motion. 1t is often convenient
In irrigation to describe a certain
volume of water in a state of rest.
The cubic foot might have been
adopted for this purpose had it not
been too small. 1t would have been
but q drop in a bucket when compared
with the large quantities used in irri.
CATION. Accordingly the acre.foot
has been quite generally accepted.
This unit represents the quantity of
water which would cover an acre to
the depth of one foot. Since there
are 1860 square feet In an acre, an
acre foot contains 1860 cubic feet.
Rainfall is measured in depth over
the surface and Of late years the ten.
dency has been to measure water for
irrigation in the same way. One fire
Quently hears it stated by practical
%irrigators that forty acres of spring
wheat will require 10 miners inches.
But this statement conveys no definite
idea as to the actual amount of water
applied to the wheat field because the
number of days the stream has been
allowed to run on the field is not
given. When, however, one states
that 20 acre.feet were applied to the
two irrigations, it shows that u GER.
tain definite volume of water was
used during stated periods, and that
this volume was sufficient to have
covered the 4O.acre field to a depth of