Yorkville enquirer. [volume] (Yorkville, S.C.) 1855-2006, 1882-03-30
WHAT MAKES FLOODS.
ANACCOUNT OF THE CAUSE OF THE MIS-.
STSSIPpI OVERFLOW.


To form proper conception of the lower
Mississippi and the cause of it's overflow, i'm.
agine the mighty stream flowing from the
mouth of the Ohio River through vast allu-
vial plain thirty miles wide and gradually
extending to width of 15G miles at the Gulf
of Mexico Through the entire length of
this plain this turbid stream flows in zig-Zag
and constantly shifting channel a distance of
nearly thousand miles to where it empties
through it's several mouths into the gulf. This
plain, containing nearly 40, 600 square miles
has been formed in the course of ages from
material brought down from the uplands of
the Mississippi and it's tributaries. Rich in
vegetable and organic matter, finely fltrated,
it is consequently one of, if not the most fer.
tile and productive region in the United
States, the richest portions being found in
'the bottom lands," Immediately contiguous
to the river and it's numerous tributaries.
Both sides are lined with plantations which
extend for miles back into the country, all OF
which are more or less under cultivation,
while thriving towns and cities dot it's banks
to the Crescent City.
THE LEvEEs.
In the summer, and when the river is low,
it's surface is depressed from 90 to 30 feet be-
low it's banks, but when the autumnal rains
set in, followed by the spring thaws, the chan
mel rapidly fills, and wherever unchecked over
flows it's banks right and left, spreading for
many miles over the great, wide, level plain.
To protect the cultivated lands from this
yearly threatened inundation they are guard
ed by artificial embankments thrown up in
front of each plantation. These are called
levees, and are hundreds of miles in extent,
almost lining the entire course of the river.
They vary in height from six to forty feet in
some places, and are proportionately thick
at the base. AS might be expected, the cost
of building and keeping in repair these i'm
mense earth structures is very heavy. In
some instances it delvolves upon the county,
in others upon the State, in many instances
upon the individual planters, and it is largely
to want of proper and comprehensive engin-
eering system capable of coping effectually
with the yearly threatened danger that the
present disaster is to be attributed.
When the channel of the river is full it's
level is many feet above that of the adjacent
country and within few inches probably of
the top of the levee. The danger arising from
it's great pressure against these artificial banks
from current Of immense volume running at
the rate of seven miles an hour can be readily
estimated.
IN DANGER-TIIE CREvAssE.
At such times the people live in constant
dread of inundation, and are called upon to ex-
ercise the keenest vigilance to prevent catas-
trophe. Neither money, labor nor time is
spared in such emergencies. The entire neigh
borhood is summoned to action, all weak
points are at once strengthened, new levees
are sometimes erected in the rear like Sec
ond line of Notifications guards patrol the
banks day and night searching for the least
leak in the earth wall, or the faintest stopping
over the top, for woe betide the section that
allows one to escape notice. In very short
time the bank melts before it like dissolving
sugar and pressing wall of water cuts its way
through, making the dreaded crevasse. A
crevassee or break in the levee once made is
rarely closed, and only then under exception
al circumstances and with great difficulty.
A torrent of water several feet high pouring
through an opening of crumbling earth walls
is no easy thing to check, and in fact, rarely
is checked. Unless there is existing, or has
been erected, "a protection levee in the rear
it only takes very few hours for the sea of
waters to spread over miles Of the level, cult
waited valley, drowning the crops, destroying
stock and spreading ruin and desolation broad
cast.
The only method ever successful in stopping
crevasses is by driving strong piles and filling
up the interstices with sand bags, but this
method is only effective in minor instances,
since once under headway nothing can with
stand the force of the rushing waters Under
the circumstances it is impossible to estimate
the losses and suffering incurred by the victims
of the late overflow. The inundated district
is so vast in extent and may be submerged
with it's devastated crops for so many weeks,
during which period it's people will remain