Green-Mountain freeman. [volume] (Montpelier, Vt.) 1844-1884, 1882-09-06
Plans for ihp Improvement of the MissiS-
Siuui

Plans for thc Improvement of the MissiS.
SipD.
A brief statement of the main theories
advanced, however, is Of great interest
especially in view of the fact that the GOV.
ernment at Washington has adopted one,
and appropriated few millions for the
| beginning of II work that is to cost mot
more than $4,000 000," its advocates say.
Theorists seek in two directions for an
answer. On the Que hand, it is urged that
| by improving the character of the bedand
Strengthening the banks the river may be
| kept within its bounds. On the other. it
is declared that no works are practically
possible that will be sufficient to contine
the river in flood season, and that since
it must overflow its banks the philosophic-
al thing to do is TO provide auxiliary chan.
nels or outlets that shall guide the surplus
water to the sea without damage. Theo-
rists of each school denounces those of the
other as incompetent automatically wrong,
and stoop 10 personal abuse when argu.
ment fails. Only short time ago Mr.
Edward Atkinson in concluding an able
argument in favor of the plans adopted by
the Mississippi river commission, said !;
|
projects for relieving the Mississippi river
| floods by creating new outlets, since these
sensational propositions have commended
themselves only to unthinking minds, and
have no support among engineers"
While this style of argument has been
too often replied upon by both sides, the
fact remains that the only considerable
works undertaken by our race have been
in the direction of trying to confne the
river, and not of trying to give additional
outlets for surplus or flood water. The
"levee and jetty advocates have had their
way so far as actual operations have gone,
and they seem likely to continue to have
it for some time. The present operations
are under the direction of the Mississippi
river commissioner body which was
created by the forty-sixth congress. Pres
ident Hayes was given the power to create
its individuality, which he did by appoint
ing only known and committed advocates
of the restrictive theory on the list of
members. Effortswere made to secure the
appointment of some of the opponents OF
this theory, but the efforts were unsuccess-
full.
The outlet theory is one which hardly
needs description to be generally under
stood, though it has been studied and set
forth by several persons with much atten.
ton to the engineering details involved.
BY glance at any large map ofthe lower
Mississippi the great number of bayons
and natura! outlets formed by the natural
action of the river will be discerned.
Some Of these it is proposed to open and
clean out, SO as TO render them available
in case of floods, and then, by lock gates
ut the river side, keep them closed at low
water, and open when the water rises toe
high The main objection to this theory
is on the ground that tho real desideratum
is single deep channel, as realizing the
least friction between the river and its
channel rather than multiplicity o
channels.
The levee, jetty, and rovetment system
is not so simple. Its claims arc far more
elaborate, and the criticisms that are offer
ell are far more complicated than those o
the outlet system. The radical idea
involved is the building of artificial banks
that shall coniine the river within them
IN order to secure the full force ant
"scuur' of the stream for the improve
ment of the bed. The obvious effects o
such works-obvious, that is, to all who
2 have given the subject OF river hydraulic
, any careful study-are such as to lead t.
careful theorizing TO Justify them; and il
; the various steps Of this theorizing ther,
is'plenty Of room for cavil, ifnot for sounI
} criticism.
Without entering the list either rs advo
cate OF critic, it is sufficient to give here
brief description of what has been done
= what it is decided to do, what it is claimc'
the benefit will be, and what the objcG
tions are. The public prints during tn
period of sub5dence of the recent flood
were full of references to the proposed
works, and TO those which had been con
structed and yet it was difficult, if no
impossible, to catch from the discussion
complete idea of the system.
The first works of which we know dc
linitely were the lcvoes. These are larg
7 banks of earth built to serve as extra bank
( if the river should rise, and to keep tn
I water Off the low, cultivated lands behin(
, them. When we'll built they undoubtedl,
serve this purpose, and if kept in repai
/ they can be made TO resist any flood that i
} ever likely TO come. The whole city o
Cairo, during the floods this year, stooC
, about fourteen feet below the surface o
l the water outside, which rose TO the yer,
top of the surrounding levees. When th,
, ripples washed on the top OF the leveos tn
+ people turned out, and built a temporary
= bank above to the height OF two feet; and
although the water rose sixteen inche
" against this hastily constructed barrier
L the town was saved.
p But however we'll levee may serve tt
protect one spot of land, it does this t.
detriment of other places, since the waite
i kept from one place flows to another, AM
e being out of its banks, is spread to place
q that would be untouched if u portion of it
II natural overflow were not walled in
!, Therefore the levee system, to be perfect
should be continuous along both sides @
y the river. Mathematcally speaking,
IS defect anywhere would vitiate the Who'll
r system; but practically it is claimed tina
. the levees constructed by slave labor, an
y kept in order before the war, worked fair
o ly well. 1t should be remembered, how
It ever, that during the years when thi
d system was in its best condition there wer
no such floods as have happened at othe
times.
o The next work of importance in the lin
l. of restriction was that done by captai
Is Eads in the south pass OF the MissiSsipI
=. delta. He conceived the idea, or, at leas
executed iD of confning wide, shallo'
l. stream within comparatively narrowbank
IS arguing that if the water could not pas
is over the wide space, it would scour OF
=, the bottom, and so deepen the channe
~ During the construction of the jetties
ol was found that the water, instead of scoul
Is ing out tho bottom, preferred to follow il
o old habit of seeking the line of least resis
a ance. Finding an obstruction in Its wa
., in tho south pass, it turned off throug
III the southwest pass, and the arOutrt
N 1t was found that instead of securing OF
/ the jeltied pass, it was securing out tn
"a other two, and there was shortly an add
:, lonal depth of two feet In each of thest
~ Captain Eads says; ''as soon as this fat
I'd was discovered submerged dams wer
10 laid across the southwest pass and the Pa
or n lOutre, about two feet thick and abou
seventy five feet width of base, Each {
IL these dams is about throcquartors of
1t mile in length"
BY thus partially damming the otho