White Bluffs spokesman. [volume] (White Bluffs, Wash.) 1907-1938, 1930-08-22

rivers, it possesses in the Mississippi.
Missouri the longest of them all.
This magnitude of the Mississippi is
becoming more and more of a menace
because each flood seems greater than
the preceding one. Why this should
be true has been a problem to some
laymen; but one of the chief factors
Is plain enough: it is the usually laud-
able effort of Americans to develop
and build up their country.
Aside from the fact that several de.
cades ago there were fewer people liv.
ing and fewer dollars invested in the
regions subject to overflow in the low
er Mississippi valley, the flood stages
were actually lower in those days.
Ihey were lower, to consider one i'm
portant fact, for the very good reason
that then less water was fed into the
Mississippi's 100000 tributaries in a
given space of time. Forests and
woodlands that do not now exist held
a large part of the rainfall and fed it
slowly into brooks and creeks and
rivers. Irregularities in the lie of the
land formed puddles that later evap
grated, or sent rills in tortuous paths
that slowed up the runoff.
In late years constantly increasing
population has been busy changing
these conditions. Every tree cut, ev
cry roof built, every street paved, ev
cry drainage ditch dug. and every cul
vert constructed in the vast area
drained by the Mississippi river sys
TEN has done it's bit toward pouring
rainfall more quickly into the great
river.
Not only has man helped to put
more water into the Mississippi; his
works have helped to confne it there
When De Soto and his followers first
knew the Mississippi 1t spread out at
each flood season over wide area
Sometimes in it's lower reaches it was
co., 80, and even 40 miles wide.
The fact that the flood waters
spilled away at numerous places into
swamps and lowlands kept the flood
crest down in the lower river In
l717 three-foot levees protected New
Orleans. Now they rise 25 feet OF
more above the city. Even as late as
1882 the highest flood stage at New
Orleans was 16 feet. In 1929 it was
above % feet. One reason, at least,
for this, is that more efficient levee
maintenance for many hundreds of
miles along the river has herded the
flood waters past New Orleans as we'll
as other lower river points in the reg
ular channel.
Levees Protect Vast Areas.
More intensive development OF tho
lowlands has made this levee system
necessary. Now some 10000 square
miles are dependent on the levees for
protection. Breaks still occur. and
when they do they drain off some OF
the flood waters and so relieve in some
measure the strain on the banks far
Their down stream. But it is not tho
innocuous affair that 1t was in tho
days of De Soto. Now towns and plan
tations, railways and industrial plants
lie in the lowlands, and any "relef"
that a levee break may occasion to
down-river points is at cost of many
lives and much valuable property.
On the whole considerable guam.
tity of water finds it's way from thu
lower Mississipr: through levee breaki
and bayous. The most important nat
ural safety valve is the Atchafalaya
river or bayou which flows away from
the Mississippi at the mouth of thu
Red river, and finds It's way directly
to the Gulf Of Mexico some so milea
west Of New Orleans. In food times
this out-flowing stream takes from the
swollen Mississippi as much as 100000
rubic feet Of water each second-an
equal to more than half the
average flow of the Mississippi. It is
because of such losses as this, coupled
with the much greater depth of tho
channel in the lower river, that the
food stage can be between so and 60
FEET at Memphis and Vicksburg, and
,nly little more than 20 at New Or.
cans.
The Mississippi river system Is truly
| continental feature draining a mil.
ion and quarter Of the three million
odd square miles of the United States.
thirty of the 4S states send greater
,r less contribution of water to this
,reat stream.
The main Mississippi river is more
han $500 miles long. while the Mis-
issippi- Missouri is 1900 miles in
ength-the longest river system in
he world. The great scale on which
he Mississippi Is built becomes evil
lent when one considers the time re.
Iuired for floods to pass down its
curse. About thirty days are re
Iuired for the surging flood crest to
,ass from the mouth of the Ohio to |
lew Orleans, and from ten days to
wo weeks from Greenville, Miss, to