The Winslow mail., 1911-06-03
DRAINAGE is NEEDED
Apparent in Every Section Where
Irrigation Is Practiced.
Water-Logglng Of Lands Is Not Con.
lined to Any Particular Part
Makes Its Appearance Even on
the Bench Lands.

The necessity of draining irri-
gated lands has become apparent,
not only in every section of our
own arid west, but in every coun-
try where irrigation is practiced. In
dia and Egypt and Spain have their
problems and their characteristics are
mucn the same as our own. A con-
servatlve estimate shows that nearly
a million acres Of valuable land in
the west are in need of drainage. The
Water-logging of the irrigated lands Is
not confined to any particular section.
1t makes its appearance in the river
bottoms and in low lying swales and
depressions, as would be expected, but
1t does not stop there. The gentle
slopes. the hillsides, yes, even the
bench lands are attacked.
l once saw a tule swami on a
hillside that had slope of 20 de-
grees and one of the wettest proposi-
t1ons l ever encountered was on the
very brow of a high gravel bench,
300 feet higher than it's drainage basin,
writes B. A. Hart, in the Denver Field
and Farm. Nor is waterlogging confined
to any particular soil type-clay, silt,
sand and gravelly lands are all suscep-
t1ble to its ravages, Many men have
declared that their lands will never
gravel sub-soil. have found, however,
that gravel sub-soil is often source
of drainage. Everyone realizes the
need of drainage on humid lands, but
few understand the necessity or even
the possibility of draining irrigated
lands. AS matter Of fact, it's neces-
sity is even more imperative than in
humid sections for the reason that wa
ter-logging in the west is always ac-
companied by concentration Of alka-
Ii salts on and near the surface. Ger
tain Of these salts are necessary to
plant growths but certain others are
exceedingly injurious. Water-logging
Is the natural result of over-irrigation
and is made natural by the absence of
natural drainage outlets. The soil
filling of valley consists of decom-
posed rock and is often very deep. The
light and the evaporation factor high.
so that little water percolates down
ward through the soil and as a conse-
quence the ground water reservoir is
usually well below the surface pre-
vious to the irrigation of valley.
1t has been demonstrated that a
rainfall Of 18 inches properly distrib-
uted will produce crops. The plant, of
course, receives only part Of this
amount. Much is lost by evaporation
and some by percolation. When irri-
cation is practiced, however, from two
to twenty times this amount of water
is supplied. The plant undoubtedly
uses more than before, more is lost
by evaporation, but by far the larger
part of the excess percolates down
ward through the soil and eventually
finds its way to the ground water res
ervoir, the level of which is thus raised
year by year until finally water-logging
and the attendant alkali troubles re
suit. The bogs usually appear in the
lowest part of the valley first, while
the alkali shows up on slight eleva-
tions
Having once begun, the spread of
the seepage is rapid and the infection
makes it's way up the slopes until
eventually even the highest parts are
injured. The appearance of the bogs
is viewed with alarm and their spread
with CONSERVATION by the farmers who
are steadily driven back, abandoning
their farms and taking up higher lands
from which in turn they are often in
danger Of abandonment. But, not
withstanding the intensity of the alarm,
it never occurs to these same farm
ers to reduce the supply of water that
is doing the damage-in fact, they