The Barre daily times. (Barre, Vt.) 1897-1959, 1909-06-22
SEWAGE DIsINFEcrIoN.
The Modern Treatment Of an Old Prob
lem.

lem.
The problem Of purifying sewage 50
that it no longer transforms the river
into which it Is discharged into open sew.
ers has been 80 far solved that these
streams need no longer be disgusting to
the senses and dangerous to the health
of people living along them The task
of destroying disease breeding bacteria
IN the sewage and once more making
the rivers available for drinking water
has not yet been worked out on a prac-
tieal basis, but investigations recently
made by the United States geological
survey in cooperation with the Sanitary
Research Laboratory Of the Massaehu-
sets institute OF Technology and local
authorities at Boston, 1T Baltimore, and
at Red Bank, n J., show that this end
too, may be attained at q reasonable
cost.
Tho essential agents Of sewage purifi.
cation are provided and employed b. ma
ture, and sewage publication as prnc-
ticed to-day ia but the intensive applica
ton Of these natural processes. The inn
not involved the discovery or application
Of new principles. but have merely in-
creased the working efficiency Of the nat
ural agencies From the Old time sewage
irrigation field with it's maximum ca.
pacity Of perhaps 10000 gallons an acre
IN twenty-four hours, to the present day
trickling filter capable of dealing with
two or three million gallons an acre a
day, improvement has been steady
The old-time methods. however, really
destroyed the polluting substances, while.
the modern sewage filter does not. The
liquid flowing from these filters looks
TO the unframed eye like the original
sewage. There Is almost as much organic
matter IN it as IN the raw sewage, and
sometimes more. Its nature. however,
has been changed; the organic matter,
though not burned up, has been charred
Of partly oxidized, and this charring
has been sufficient To rob it Of its foul
ness In other words, its chemical COM
position has been 50 altered that it can
no longer undergo rapid putrefaction and
cause a nuisance.
The water, however, still needs iiltra-
ton to make it fit to drink. Moreover,
1T may aud in many cases does contain.
mate oyster beds, thus spreading disease
and tending Of ruin a great industry.
1t has not yet been decided upon
whom the responsibility rests for keep
ing the rivers clean. but the consensus
of competent opinion requires that If
sewage Is discharged within the region
of important shelfsh beds or into
stream which is used as a source of do
nestle water supply without filtration,
such sewage shall ct least be free from
disease bearing germs.
Results Of Geological Survey Expert
ments.
The geological survey experiments,
which are set forth by Earle 3. Phelps
in Water supply Paper 22a, just issued,
show that the application Of small
amount Of available chlorine IN tile form
Of bleaching powder to the customary
purified sewage effects satisfactory dis
THE removal Of bacteria by
this means averages over 05 per cent.
making the removal for the whole purif
cation process 9s to 80 per cent. Of the
number in the crude sewage. The cost
Of disinfection ranges from 81 to Sl.50l
per million gallons Of sewage, depending
chiefly on the size Of the plant Five
parts per million Of chlorine probably rep
resents the maximum amount required
fofthe treatment Of trickling filter eiflu-
ents Of poorer quality. The results Oh
tanned with the amounts Of disinfeetant
specified do not Of course, amount to
sterilization. but they may
a.. ~ al d. 4
ton" Considerable additional cost is re
quired to improve them but slightly. Mr.
Phelps paper may be obtained. free Of
cost, from the Director. United States |
Geological Survey Washington p. G.