Public ledger. [volume] (Memphis, Tenn.) 1865-1893, 1876-04-26
TIE LEVEE QUESTION.

In your Fridays issue appears an ar
ticle discussing the high water and the
effect of levees upon the rise and fall Of
water in the Mississippi Valley, and as
this is a subject promising to become
national in Importance, you will pardon
me if l ask space to call attention to
what seems to me to be an error in your
conclusion, after presenting the facts.
You state that the river at Chicot,
some 200 miles below here on the Arkan-
sas side, is twelve to eighteen inches
higher than ever before known, and
argue from this that the levees produce
the effect.
Is it not a little curious that the river
has not reached the highest food line at
Cairo, or Memphis, or Helena, or the
mouth of the Arkansas river above
Chicot, or at Vicksburg or New Orleans
below2 The cause, therefore, is necessari-
ly local. 1t is not attributable to Arkan
sas and White rivers, because the Mis-
sissippi at the mouth Of these streams
has not yet reached the highest food
line. These are known facts.
Again, the vicinity Of Chicot presents
the only considerable extent Of country
from Memphis to New Orleans where
the country on both sides of the river is
overfowed, and yet this is the only Sec
ton of this country where the levees are
broken to any considerable extent on
beth sides of the river.
From Memphis to Chicot there are
comparatively no levees on the west
bank Of the river. On the east bank Of
the river from Memphis to the vicinity
of Chicot the leVees are comparatively
intact.
In the upper end of Bolivar county,
Mississippi, some thirty-fve miles above
this point, is the first clevasse Of any
importance, while below, in the immedi.
ate vicinity, are several large openings,
devastating the whole country on the
east.
Now, sir, p~aradoxical as it may ap-
pear, | assert hat crevssses in the levee,
instead Of permanently reducing the
height Of the water in the channel, ab.
solutely produce results directly the re.
verse, as we see at Chicot, and as we saw
demonstrated by the high waters of 1858
and 1859, fully discussed by me some
time since in the Avalanche. Here is
the indisputable fact thatthis is the only
point from this to New Orleans where
any considerable portion Of the country
on both sides Of the river mas passed be.
yond previous foods. If your theory
be correct, the aood.line should have
been reduced, not elevated.
Let us see if it is possible to reconcile
the apparent contradiction in the propo-
Sition submit upon any reasonable phil
osophical principle. The fall, back from
the brink Of the river, averages about
five feet for the FIRST mile, often consider.
ably more, rarely less. This of course
is increased as the water is raised above
the bank by a levee, so that if a leyee
with FIVE feet depth Of water against il
give way, it gives the food a fall of ten
feet at least for the first mile. This nee.
essarily produces a powerful lateral cur.
rent-powerful in proportion to the fall
and the volume Of water passing ont.
This directly affects the forward active
current in the channel Of the river, often
almost destroying it, produces an eddy
below the crevasse, which deposits the
sand on the bottom and builds a dam in
the channel of the river. This is no
theory, but an actual effect produced by
an adequate cause, and the more fire.
quently it occurs tie more serious the
loss to the ~discharging capacity of the
channel in compelling the water to climb
over these ridges thus formed in the chan.
mel Of the river until it produces the re-
suit as demonstrated in the vicinity Of
Chicot, the overflow through the crevasse
not compensating for the loss of both
speed and space in the channel. C.