New Orleans Republican. [volume] (New Orleans, La) 1867-1878, 1874-02-04
.'DEEPENING" THE PASSES.
Essay Against the Improvement Of Navi
cation ut the Mouths of the Mississippi
River by Mems Of Jetties.
.Yc.G. FoRsHEY, CIVIL ENcI.EER.


Read before the New Orleans Chamber OF
Commerce upon resolution pendins, ue!-
rccating the action of the st. Louis Mer
chants Exchange in its support OF Captain
Eads method and proposition to Congress,
February ,, 1874
The appearance of the letter and COM
munication of Captain James Il. Edds IN
the papers of the day, as addressed TO Sen
ator SchurZ Of Missouri, upon the SUBJECT OF
t'deepening the mouth or mouths OF the Mis-
sissippi river would seem to call for spe-
cial comment from men of science, as well
as from all those specially interested II the
commerce of the river and valley.
Captain Eads proposes for himself and
friends, to relieve the public anxiety and i'll.
terest raised by the necessity OF IL deeper
channel for navigation, by a contract with
the United States government to clear out
one, at least, of the river mouths. To the
depth of twenty-eight feet; and this accom-
plished, to receive S5,000,000 for the work.
aud then to receive half million annually
for keeping the channel at twenty-elght feet
for ten years after completion. Another
condition. and one of significant import
ance, provides that when q depth OF twenty
feet shall have been attained. he .han &c.
etive S3,000,0O3.
The boldne-s of this proposition. coming
from man whose successes in grea: en-
gineeling enterprise, that of bridging the
same river at ST. Louis. 1890 miles above
The mouth. have given him Just prestige
in his profession, is calculated 10 stagger. at
least for the moment, tn. resolutions Of
many who had been led led by past failures
of O similar kind. to advocate the plan OF
canal cut from deep water in tins river TO
.Ieep water in the Gulf Sew ui!es above
,he head of the passes.
But for this prestige OF captain Eais.
snd the earnestness with which he alleges
shat he evil have no difficulty III cOnVinc.
ing the honorable Missouri Senator OF the
Feasibility of his pian.' j. %ouli scarcely
be worth the while to revive and secap.tI'
tate all that has been done and sad by the
best informed engineers in private life. and
Che ablest BODY of United States engineers
ever assembled in America, all resulting il;
AN abandonment, for the present at least.
eff the Sysyphus Labor OF dredging the
mouths OF the .!ytrs .S sie.e:e.ce - the
plan of q canal.
However, nrieS sifnmarc o! sspsr.'
mental labors In this .irection may he
Useful, in immediate connection with
Captain Eads' proposition to furnish ten
years navigation q! !wensveigh: feet for
SIC, 600; or 20 carry the work ut twenty
feet depth. ana receive S2,00o.0o'. even
should he .hen iini !: cynyea.ea: -
ebandon it.
The engineering aspect of this .n'err''s"
mas these testimonies agains. the uroyOs1.
ton of Captain lads:
/. The surveys and soundings about Che
mouth of the river, since El9. a period of
I55 years, have shown the water on the bar
of the several mouths to have been fourteen
to sixteen feet, IN IA state of nature no two
passes, ever having had so great depth at
the same time, for any nentionable period.
Nor has the water depth on any one Of the
l.. 7 -.
whole season.
mean depth OF fourteen AMI "ue-haif
feet NAV be stated az the normal depth of
the water on the best aud deepest ha.. .US
$50 years.
Alike testimony shows the river eue-
rents to have deposited a plastic and yield.
ing bar of such softness that no permanent
works could be constructed thereon. The
French Fort constructed at the mouth Of
Balze bayou Whose locality was remem-
bered), could not be found, on the Kicker
survey OF 1919. lJ was of brick and Of q
broad base: vet the magazine had sunk
below the prairie.
The qualification of the strata at the
proposed canal below Fort st. Philip was
demonstrated in the borings of Major
Howell.
3. In 1888 Captain Talcott, a most able
and skilled officer of the United States en-
gneers, made an elaborate examination at
the Southwest Pass IA channel made chiefly
since l7l9, and unnoticed on some of the
maps, and having bat seven feet water On
IN Its bari, undertook to drcdge a channel
for commerce, under orders from his gov
eminent, and although he succeeded in cut
ting channel through this plastic mud
with eighteen feet water, a few months OF
current operations and the lateral pressure
Obliteratel all trace Of his work.
4. In the wear lS,,O a survey was made OF
the river, below the city Of New Orleans.
through all the passes. This was under
senator Kicker. as chairman of the Levee
Committee-Professor Forshey, civil engi-
neer, conducting the professional work.
Every pass was sounded and perforated.
TO test the character of the bottom. The
channels over the bars sounded were as fol.
lows:
Pascal Odtre, eleven feet; Pascal Outre.
nine feet five inches-north channel; North
east Pass. eight feet: Southeast Pass, eight
feet, reached through Seim bayou: South
Pass, four feet (i). could not get out with
steamer: Southwest Pass, fifteen feet.
The pertorations of those bars We're made
with smooth. two-lnch pole, shod with an
iron socket and spear point.
The weight of a man thrust this pole nine
feet in the Southwest Pass bar, on a mud
lump recently heaved up to the surface.
similar results were found at all the bars
and upon all the mud Jumps about the
outlets.
The conclusions of this survey are thus
stated in the engineer report to senator
Kicker and published in public document
bv the Legislature of 1851. Il
The bars OF the passes are composed Oh
,Sevieny gives fourteen feet in the Balse bayou,
4 Fh W he navigation