The Providence news. (Providence [R.I.]) 1891-1906, 1902-05-05

labor. and an extra plart for washing
and steriiizing the beds. and the wear
OF machinery; also extra water TO be
pumped Tor washing the mechanical
plants. as the amount filtered and usea
Tor washing the mechanical plants Is
largely in excess OF the amount required
for natural filters. The question OF
maintenance IS of great impor .ance. aLu
your committee find that the cost of
natural fitration viii be less and will not
require such constant care to guard
against injury by the use of coagulants
as the mechanical system
: The natural slow sand system OF ~
tration has been adopted by -the-city or
Philadelphia. l50.o0o0oo gallons, city OF
Washington. ,60.0J0.OO0 gallons and city Of
Pittsburg, 75,0C0.000 gallons daily use as
these large cities have thoroughly invrs-
tigated these matters and are satisfied
that they will get the best results from
this system.
Ore OF the beet known mechanical
plants is at Lorraine, Ohio. OF 100000 ga.-
Ions .capac.6y that is reported as using
.2-lO grains of alum per gallon at a cost
! 3-10 cents per pound Or $s.2S per mil
lion gallons: this would be for alum
alone. Is per cent more than was paid tor
the total cost OF maintenance at the AL
bany slow sand filtration Plant per mil
lion gallons OF filtered water.
DETAILS DIFFICULT TO SECURE.
We have been unable to determine or
get the information required to know the
exact amount OF sulphate of alumina or
alum used, except that taken from the
reports of the East Providence and Lo-
raine. Ohio, mechanical pants.
Reports OF other plants while giving
In some cases the efficiency, fail to give
the cost OF maintenance. A fair estimate
OF the amount of water used In this Guy
for manufacturing purposes Is about so
per cent OF the whole amount sold We
are convinced. that II would be detrimen-
tai 10 the best interests of the city espc-
cially for manufacturing purposes to
adopt any system OF filtration where. BY
the use of Chemicals. the city takes
chances of materially changing the char
acter of the water. Another serious OBJ
lection 10 the adoption OF any system of
filtration that requires any kind of chem
icals or coagulants for filtration. is the
question of health. while doctors may
disagree as to its effects. the pu5i!c ger-
orally will not have confidence In the
sulphate Of alumina or alum process, but
We believe Will persist IN buyirg the
spring water that Is sold now in large
quantities. 80 oiir citizens
II Is claimed by the advocates OF Ne
ohanical Filtration that that system pro-
duccs brighter or clearer water and
20 the public IL the Pnwtuxct river water
were highly colored, as many rivers In
the South and West are known TO be-
this claim might control leaving out the
more important question OF the fleet up-
on the public health by the use OF sui
phatc OF alum!na or alum. But as the
Pawtuxet river water Is mpara lively
clear In its natural state. we believe that
the results OF sand lltra ton will be en-
tirely satisfactory ia this respect
In view OF the facts and after careful
consideration OF the whole subject, your
committee unanimously recommend t..at
your honorable body order the Install
ment OF natural or slow sand filtration
plant on the land now owned by the city
OF Providence at Pettaconset,. and pr =
sent herewith an ordinance and unanl-
mously urge the passage OF the same.
Respectfully submitted.
WILLIAM II. REYNOLDS.
Chairman;
WILLIAM n. COVELL,
STEPHEN A. COOKE,
BENJAMIN W. SPHINX,
ALLEN A. PRESBREI.
HENRY FLETCHER,
GEO. II. GRANT.
Commit feo