Rock Island Argus. (Rock Island, Ill.) 1893-1920, 1902-11-18
DOES A RIVER PURIFY
ITSELF IN 90 MILES?


The issue between Chicago and st
Louis, occasioned by the opening of
the Chicago drainage canal, through
which the sewage of Chicago is con
Quoted to the Mississippi river, vi,
Des PLANES and Illinois rivers, is
based upon the condition in the
minds of the people of St. Louis that
there will arise effects detrimental
to the water of the Mississippi river
at that city. The whole dispute cen
tiers, therefore, about the old mooted
question as to how long distance it
is necessary for river to flow in or
der to purify itself. states a bulletin
issued by the government geological
survey. So
We know from chemical analysis
and physical examination that vary
ing degree of publication takes place
in river. In early days this was
thought to be due to aeration, and
the tumbling of water down noun
tain sides became the basis of poetic
Implication of purity. The experiments
of the Massachusetts state board of
health have shown that the aeration
has little or no. effect upon the condi-
ton of organic matter in water-that
is, the organic matter is not assisted
in its oxidation by agitation in the
air. 1t was ALSO found that the high
est degree of activity in oxidation
processes is to be found in quiescent
or stagnant waters. 1t then became
clear that qualification i'm a slug
gish stream is far more effective
than in Il swift current, and that
dams and other impediments have a
beneficial effect upon the condition of
water in river channels.
The PRONUNCIATION of these facts led
To an entire change in the ideas con
corning the distance necessary for
stream publication, and it is now
understood that no hard and fast
rules can be set for guidance in de-
termining the purifying power of any
watercourse. y royal commission, APP
pointed to inquire into the conditions
of England's rivers, reported to the
English parliament in the early sew.
entities, held that no stream in the
United Kingdom was sufficiently long
to effect its own publication. The
familiar and oft-quoted principle is
that stream purifes itself in 20
miles, but how this distance was ever
determined or who was responsible
for its general acceptance is a matter
of doubt; certain it is that the state
ment is entirely wrong in the MAORI
ty of cases. Pettenkoffer. Herring
Stearns and others have given formu-
lac which are undoubtedly for the
rivers upon which these gentlemen
worked, but which can in no wise be
accepted for rivers in general, and ii
remains for the investigator to de-
termine by actual experiment the
purifying power of each stream with
which he has to deal.
The work of examination of the
surface waters of the United States.
Recently inaugurated in the division
of photography of the United States
geological, survey. in cooperate
with the various college laboratories
throughout the country will be use
full in the determination of the self
purifying powers of many of the in
terstate rivers. These results will be
highly beneficial to the municipalities
and corporations which may be look
ing toward the establishment of sew
erage systems and publication works.
During the coming winter it is eN-
pected that NJ. O. Leighton, hydro
grapher of the geological survey,
will take up this work upon various
rivers in Indiana and Illinois. and will
so far as possible extend this research
to the streams which at the present
time are of great interest to the in
habitants of the Mississippi valley.