Omaha daily bee., 1896-12-27
Largest Purifying Plant in the World Con
struc cd at Davenport,
SOLVES THE WATER SUPPLY QUESTION
4 New and Effective Method of Filter
ing the water IoG the M!ssis-
slppi Rivcr-Eraturcs of
the Plant.

plant is $l,2OO,OOO. The ten double flte,
shells, which contain the immediate water
supply, have a capacity of 7,50OOOO gallons
The Mississippi river is the source from
which the water supply originally comes
relates the Chicago Times Herald The
water is drawn from a point in the bed OF
the river nearest the channel down into q
! tunnel that passes under the rivers bed for
considerable distance Through this tun-
mel IL sweeps to the pump wells. and thence
into the filters. There is no danger of con
taminatiCn, as far as the sewage is con.
cerned. for the point in the river from which
water Is secured is a mile and half above
the government bridge and the point at
which the Davenport sewers enter the river
At this same point the Mississippi has a
current of about five miles an hour, and
dashes over the Rock Island rapids, giving
1t complete aeration, oxidation and dilution.
all of which tend to its publication
The filter plant is in itself a most mar
veous sight. Each of these shells is nine
and half feet in diameter and thirty-two
feet long. They are built of homogeneous
steel of tensile strength. The water COM
pany has so far built about thirty-seven
miles OF mains into which the purified water
flows from the filters.
Despite the fact that there are ten filter
shells so delicate is the construction from
a mechanical standpoint of the entire plant,
time or in their entirety, as circumstances
may make 1t advisable AS an indication OF
the effort that has been made to provide
this plant with every possible means of
purifying the water 1t may be stated that
each fter is about three-quarters full of
white sand. amounting to about thirty car
loads for all the filters.
This sand Is brought from Horn Island, in
the Gulf of Mexico The peculiar nature of
this sand is that each grain is of almost
,,o1 III 1ta1 i- L.
brand new. and very costly departure. The
ordinary sand that is used for fltering pur
poses is porous. and therefore does not in all
respects answer the requirements. This,
however, is the first time that a city of any
size has so filtered it's water supply.
1t must be remembered that water always
contains microbes. Sometimes they are so
inflnitesimally small that only a magnifying
glass OF exceeding power twill detect them.
If there were not sand in the filters that wa!
absolutely impervious to the attacks OF the
these little seeds of death would
be quite likely to find lodgment in the pores
of the sand. There they would die and rot.
and in a short time tho sand would become
a fruitful source of disease. rather than a
plant to purify water! This is why Horn
Island sand is used in Davenport.
Ii all the rivers in the country barring the
Chicago river, had been considered as a max
imum test for this big plant, no better selec-
ton could have been made than the Missis-
sippi river. While the bel Of this river is
composed to a great extent OF constantly
shifting sand. there Is at all times a pro-
sediment in the water which gives
II that peculiar yellowish color which has
made 1t famous the only real water in
America that hardly resembles water at all
with the exception that 1t is liquid in form.
At certain seasons of the year if glass be
illed with Mississippi river water and al
lowed to stand for few moments il will be
'ound that almost one-fourth OF the glass
rom the bottom up will contain liquid mud
Ihat Is why ii is so often said that the per-
sons who drink uniltered Mississippi river
water absorb their peck of dnt every forty
eight hours
So the task of the big filter plant at Dav-
EXPORT is no light one and the amount of
dirt and impurities that are removed from
The 100000 gallons the filters contain is
naturally tremendous in quantity Espeeially
ioes this fact prove impressive when 1t is
considered that the 1900 900 gallons the |
filters hold simply constitute the amount that |
IS in them at all times. OF course the water |
S constantly changing. Every moment it is |
being pumped out into the thirty-seven |
niles of mains that wind like snakes beneath |
he surface of DavenpOrt's streets To filter |
he entire water supply of a city is gigantic |
ask
The method OF filtration is interesting and |
entirely new, because il must be remem-
)ered that there Is not in existence any
iltering plant that approaches this in mag
litude or completeness in the way of pos-
essing every requisite for removing i'm
'urlties from water In the first place, the
water, as 1t comes from the Mississippi via
he tunnel beneath the rivers bed is forced
" pumps through twenty-inch feed mains
nto the filters. Then it passed downward
through five feet of sand ard thence through
peculiar shaped screen. consisting of eX-
remely fine sits sawed through cylinders
I heavy seamless tubing. After this 1t goes
nto the mains and is forced out to the con-
umer.
Nov look at the water ard compare IL
With the muddy, amber-colored fluid that
ows into the filters from the tunnel 1t
as become as bright, as clear and as spark
ng as If it came from spring.
The sediment and all the microbes that the
nfiltered water yields necessarily remain
n top of the sand in the filters 1t is in
ne economical and certain removal of this
npure matter that the chief excellence of
lis great plant lies. The progress of cleans
lg the sand is not unlike that operative
hydraulic mining, Thousands of fine |
owerful jets OF water are applied directly |
} the place where the impurities are located
I the same time the sand is washed by | ;
'rcing the water upward through the bed |
sand, instead of allowing the water TO
enetrate from the top to the bottom OF
'urse this process renders 1t necessary for :
'me of the water that has been rendered
ire to be forced back but 1t is filtered |
gain, and therefore nothing is really lost. |
These jets of wafer that are used in
eansng the sand come through horizontal !
'riorated arms, running from central verti-
Il pipe which in turn Is attached to pis- |
N In such way that by admitting the '
ater pressure from tbelmains to the piston {
e perforated arms referred to are forced
Iwnward and. back through the filtering q
aterial. Thus the washing jets, each of {
hicA is three -siXteenghs of an inch in diam I
err are directly applied under eighty
'unds pressure TO every grain of sand that .
In the filter. The reauitr Of all this 10 that
ch separate particle of, the filters con-
nts Is turned around and ground until 1t
is practically been saUured Then when
the impure matter his been collected and
ats in the water at the top Of the sand
ed for filtration purposes, 1t is forced back
to the river again through a drain that is
instructed especially for that purpose
One would naturally think that where all
is was done constantly there would be no
ouble about keeping the water pure. But
chances are taken, and in order that not
e sightest impurty may remain the filter
ID sand bed are stepiiZed. This is the
st blow so far as the microbe and his at
ndant evils are concerned. The water is as |
re an II ia possible for water to be, with
o result that the little city Of Dlyenport
S the only absolutely pure water supply of
y city In the United States, II not in the
,rid.
riOus Condition of senator warren.
CHEYENNE Dec. 26.--(Special Telegram) |