Shoshone journal. [volume] (Shoshone, Idaho) 1884-1931, 1912-03-29
WHAT CAUSES SEEPED LAND
der Best of Management, Making
Drainage Essential.

(By C. C. ELLIOTT. Chief Of Drainage,
United State Bureau Of Agriculture)
The cause of seeped or oyersaturat-
ed land is the waste from irrigation
and leakage from canals and laterals-
The skillful irrigator may insist that
| If no more water is applied than is
needed for growing and maturing the
crops, and that if the canals are so
constructed that no substantial
amount of water escapes into the
earth, no land win become too wet for
farming purposes. 1t is true that in
many instances irrigators have been
unduly prodigal in the use OF water,
particularly when the land is first
subdued and watered. The art of
economical irrigation is usually learn
ed only when scarcity OF water COM
pels its less lavish use. In any event,
under methods that we may expect viii
prevail. some waste of water will 90
cur under the best Of management
making draining in many places essen
tial to profitable farming. For these
reasons an account of drainage con-
ditions in different localities and the
methods of treating them. together
with the results which have followed
various drainage operations. will be OF
interest to the holders of irrigated
farm lands
II should be observed as general
truth that water which produces per-
manent saturation rises from the bot
tom of the saturated portion toward
the surface Waste from irrigation
first passes downward until a hard
stratum of earth is reached. This
may be only few feet. in which case
the additions which accrue from the
irrigation of a few years will bring
the permanent ground water level to
within two or three feet of the sur
face. at which time injury to farm
crops will ensue The distance to
horizon of hard material may be much
greater and the intervening ground
may permit free percolation. in which
case a much longer time will be re-
nuired to fill the soil, because of the
larger reservoir capacity and the re-
lief afforded by under-drainage. 1t is
not the downward movement of water
alone which occasions DOGGY or wet
areas. but the lateral movement of
ground water down a slope until a
fat tract or surface depression checks
the flow and causes an accumulation
OF water, which is made known by its
appearance. not, however, until the
lower parts of the soil have been filed.
Such depressions OF level areas re-
ceive the accumulated waste water
proceeding from adjoining lands.
which occupy a higher level It will
be seen that the saturated condition
of the land which shows injury is not
due to the water which is applied d.
rectly to irrigate 1t, but to the surplus
which percolates from the higher
lands. sometimes through considerable
distances. until i reaches the lower
fat or depression.
Drainage has been carried on in the
west 10 such an extent that certain
methods are now practiced with rea-
sonable assurance of success. Refer
ence to some of these win indicate
the variety of procedure which is now
followed, as well as the constructive
difficulties which attend this class of
improvements. The development along
this line which has taken place during
The last five years is most encouraging
to holders of seeped land