The Rock Island Argus and daily union. (Rock Island, Ill.) 1920-1923, 1921-09-24

! crease in either size or freoue7c-
The same thing has been fopn5
true for the Ohio, Missouri and Cog
necticut rivers. A study of foot
on the Merrimac river has shown
that deforestation of 25 per cent
had no effect on them. Studies ~
floods on the Seine and the nas
ube in Europe for much lonps-
periods corroborate these concln.
sions.
/ The Real Cause of FIoods-
The real cause of our food dis
asters IS that civilization has
drawn the cities and homes dou-n
into the path of the floods. and tbst
we have not given them protectior
Railroads have followed the hot
toms of valleys because the easi
est grade is there, and the cltiss
have been built down by the rail
roads instead of up on the hills
where more primitive men genar'
ally built their homes and citiea
Our valley cities are sure N Ia
destroyed at regular intervals m
til all of them have been prcnarI,.
protected against floods. This i
the fact which must be drive,
| home. Floods are one form of his
tory which may be confidently re-
lied upon TO prove ii. ANY dwaIIa-
in an unprotected city or town in
one of our great valleys can study
a chart of the foods that have or.
CURED in the past and predict with
accuracy when he will next need \
rowboat or a life preserver. A.
least, he may predict how often
he will need it in given period If
years. Scientists have even mada
formulas for predicting floods. II
may be calculated that floods of
the greatest size on a given river
VIII occur, over a considerable
stretch Of time, once in every q
years on an average. Those of the
next magnitude will occur half a.
often on an average, and so on
down. In the diagrams which have
been prepared, it is remarkable
how regularly the high water
marks occur
There is no space in this article
for an adequate discussion of the
methods of flood prevention. There
are two chief methods-dikes or
leVees and retaining basins. We
have one of the greatest examples
Of the former in the jetties of the
lower Mississippi These have
shown the limitations of such
works. They afford local protec-
ion, but often serve TO back the
waters up in other places. caus-
ng foods where otherwise there
would be none
An excellent example of retain 4
ng basins is seen in those on the
lead of the Mississippi river, which
we're built primarily as aids to
navigation, but have had a most
important use in preventing foods.
There are no retaining basins in
his country built primarily for
iood control. but numerous basins
'reated for irrigation purposes, or
o produce water power, haTe
hown the great possibilities of tbs
method of control. In Europe re-
aiming basins have been used for
oOd control for a long time.
The best engineering opinion
GEMS to be that what the United
tateS needs is a great unified sys-
EN- of flood control, especially
Dr. the Mississippi drainage. Most
ersons do not realize what a large
art of the United States this en-
races. Waters rising to the sur
ace as far west as Montana and
ew Mexico and as far east as
ennsylvania and West Virginia a.
mately reach the Mississippi Il
in this great system Of rivers
lat most of our floods occur. The
ueblo flood was a MISSISSIPPI!
3sin flood.
Obviously food control IN this
-eat area must be handled as one
The methods adopted II
lch locality must be suited TO lis :
dividual needs, bur must also
Ike into account its effect on the 4
hole system. It is probable that
tanning basins, many Of which
i'll also serve other purposes,
Lch as irrigation or power pTOduc-
On. will be the solution OF the
oblem.