New-York tribune., 1901-03-18
FILTERING THE PASSAlC.
THE EAST JERSEY WATER COMPANY'S
PLANS.

The filter plant about 10 be constructed near
Paterson. " J.. the Passaie River. possesses
| great Importance for a number of towns IN that
Iocalitv but IL is sure 10 receive attention from
other centres Of population where the purihcation
Of the water supply is still an unsolved problem
When completed this plant Will he the largest ana
proba bly, the finest in the United States
The East Jersey Water Company already has at
Little Falls five miles above Paterson. pumps with
a capacity of about sixty million gallons daily
These pumps are ordinarily driven by water power
but the works equipped with steam power also'
for use in emergencies. Just now something IKE
thirty million gallons Of is being furnished
Jersey City from Little Fails. But thlS Is
temporary arrangement. when VIII P''"a'iy
terminate faIl winter Paterson ee'S
about fifteen million gallons more. ana a Cotre-
spending amount is divided among Passaic. Bay
onne Harrison. Kearny. West Orange. Glen hiuse'
Montclsir. Bloomfield and Franklin. Even "heh
Jersey City becomes independent. though. there
will Re an aggregate demand the Little Faiis
works for upward of thirty million sallons' and
quantity will all be filtered before 1t is de-
livered
What with the factories and sewage of Pater-
son the Passaic is a pretty filthy stream when IT
gets down TO Newark: but at Little Fails the water
much cleaner. The opinion has been expressed
that in respects il is superior to Croton
water. Still there a good many fair sized
towns along the Passaic above the East Jersey
Water Company's works: and while that corpora
tion has undertaken filtration without legal COM
pulsion and deserves much credit for the spon-
taneous adoption of that course. it probably knows
what IL is about.
The plan which Is to he carried out at Little
Falls will be better understood II the reader re-
calls the differences between two we'll known sys-
TENS of sand filtration. The flow is much more
rapid in the American system than the English
II is estimated that the output of the latter rs
scarcely more thln 100000 gallons day to each
acre of bed whereas that OF the former is between
40 0OoOJ0 and 100 .OoO fifteen or twenty fold
greater. In the great majority of the American
filter beds gravitation is the only force operating
upon the water but in few instances mechanical
pressure IS resortcd TO in order TO facilitate the
process.
second point OF difference is that in the Eng
lish system the work Of publication is performed
very largely II entirely by millions of bacteria
that cultivated in the upper layers OF the filter
These bacteria dispensed with in the American
system. but before the water enters the hitter and
is yet in settling basins a certain chemical agent
called a coagulant, is added in minute and care
fully measured quantities. The agent employed
for this work is alum. The fear has been eN-
pressed that this substance might exercise hurt
ful influence on the water But chemical analysis
seems TO show that the character Of the salt Is
changed by the operation of hltering. and that II
disappears altogether alum 1t has been alleged
that in instances there less alum in the water
after filterins than before
The sand employed in the English type of filter
bed remains in service for months Then the
upper layer is removed. fresh sand replaces II.
few bacteria introduced for seed. and in the
course Of few days the bed is again in working
order. With the American filter the material is not
changed but short intervals II is washed ont by
reversing the direction of the flow. tellylke sub
stance that has caught the various impurities is
thus automa ticslly extracted from tho htering
material.
As to the relative merits OF the two systems,
this much may he said: The slower ono is particu-
lary efficient in removing bacteria. usually taking
at least % per cent; nut produces htte eect
the color Of the water. The latter may not he
SUBSTANCES but t is unpleasant to the sight As
surances that the water Is not harmiH! doAuot
make bathing in it agreeable II Is assertedSor
the rapid American pan that II removes an , d,s-
Issoasa onrras ,tsr,,,t, ,s tbcre ~. uofab. Fif-
ferences in the character Of the water supply IN
Poy speesi board Of sani,afy Engineers to study
local conditions and oIer proper adyce ,,,..
AlbaSy. \. y. The latter has capacity OF about
Twelve million hve hundred thousand gallons day.
Experts recommended this system Tor Ptttsburg
and Moscow have been advised 70 try TIE other
plan. There are already in operation IN thlS sGGn-
tion plants Those Red Bank. y. j, with a
10 so oGD 81 Joseph GO2 0c.l. Davenport. Iowa
& 500 COO: Chattanooga ts.Gooe) and Elm!ra @."'-
The plan adopted 6y The East Jersey Water
Company is of the latter class. and the details OF II
~ FnIIer consulting engineers Thirts-two her
beds are 10 be constructed. each having capacity
uf one million gallons daily These VIII measure
Il by - feet and contain about three feet or SAND
or powdered quartz. The bottoms and Sides ot the
beds will be OF concrete. The water VIII be con
veyed from the filters to enormous wen Tor
storage For controlling the inlet valves 10 the
filters a greatly improved method viii be adopted
fhe mechanism will concentrate the levers az a
single point in way that will greatly slmphtX
and facilitate operation. These new works are All
be inclosed in building measuring leO by lte
feet and IS feet high The tdihce VIII have con
crete founda tons and walls. In fact, in the quahty
OF material and the workmanship. as well as IN IT'S
capacity the plant will be distinctly superior 20
anything else IN this country And II IS hoped that