Vermont phÅ“nix. [volume] (Brattleboro, Vt.) 1834-1955, 1890-05-16
CURRENT AFFAIRS.
THE MISSISSIPPI FLOODS.


InterestIng Facts Frsus G7eu. Greeley
81 the BiEnal Service.
The recent floods in the lower Mississippi.
the worst in its history, have aroused
great deal Of discussion concerning the
best methods Of controlling the river and
its outflow in future. An interesting con.
tribution on the subject Is an article by
Gen. A. W. Greedy, head Of the signal
service, in the current number Of the North
American Review, giving a great many
facts obtained from official records Of rain
fall aud Of the stage Of water in the lead
ing rivers Of the Mississippi basin for some
years past. One Of the interesting points
brought out by Gen Greedy is the small in.
fiuence on the volume Of the lower Missis.
sippi which is exerted by the outflow from
the upper Mississippi and the Missouri as
compared with that from the OHIO. Dur
ing the food Of the year 1882 the Missouri
valley contributed 1853 cubic miles, and the
upper Mississippi valley 8 SO cubic miles
while the Ohio valley contributed 80. AZ cubic
miles, or five times as much as the other
two together. These figures, Gen Greedy
thinks, effectually dispose of the theory
that Mississippi floods are caused by the
melting Of the snow on the Rocky Mount
aims, and of the consequent theory that
those floods might be restrained by storage
reservoirs in the upper basins Of the Mis-.
sissippi and the Missouri As TO the Ohio
river and basin, the authors opinion is that
no reservoirs could possibly be constructed
large enough to hold the overflow. During
March Of this year, he says, the rainfall
over the catchment basin Of the Ohio valley
has been at least "a cubic miles. He figures
out that Of this 1875 cubic miles went
down the Mississippi as overflow and
therefore, that in order to prevent that
overflow, the reservoirs in the Ohio valley
must contain that much water. This amount
Of water, he estimates, would cover an area
Of 1900 square miles to the depth Of FIVE
feet and no reservoir or series Of reser
voirs capable Of containing this amount of
water is practicable. His conclusion is that
1t appears evident from the above figures,
If calculations Of this kind can be depended
upon and every one must admit that en-
gineering problems are based upon calcula-
tions Of this character-that the impound
ing Of waters by reservoirs is entirely out
of the question as regards the Missouri, the
upper Mississippi and the Ohio rivers"
The figures quoted by Gen. Greedy as to
the volume Of water in the lower Mississippi
are little less than startling. In 1882, dur
ing the first three months Of the year, near
y "a cubic miles Of water passed over the
Ievees between Columbus, Ky, and Hayes's
landing, Miss. During this period the wa
ter passing Hayes's Landing amounted TO
more than 10 cubic miles. In other words,
the Mississippi river channel, bank full at
that point from January TO March inclusive,
was able TO carry off less than 20 per cent
Of the water flowing from above. Further
figures show that if all the food waters of
1882 had passed New Orleans they would
have required an increase of "a per cent in
the capacity Of the channel at that point.
Still further, the number of flood days at
Cairo has increased from an average of 22 |
in the decade of 1871 80 TO more than 40 |
lays for the succeeding decade, and at
Helena, Ark, from 40 to 20 days.
The remedy for this state Of things, Gen.
ireely says, is TO form new outlets for the |
main channel of the Mississippi river to the
Gulf Of Mexico, and to restore those which |
'nce existed but have now been closed up. |