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

. The long discussed question OF filtering
the water used in this city for drink
ing. domestic and manufacturing pur-
poses. Is about to be settled.
The Joint special committee OF the city
council. appointed in February last, made
their report to the city council in spe-
ciai session. this afternoon. recommend
ing that the municipality constructed a
sand filtration plant at Pettaconsett. on
land now owned by the city. The re-
port is as follows:
THE COMMITTEES REPORT. -
The Joint special committee appointed
BY resolution No. 81. approved Feb. 4.
1902. 10 consider and report as. TO the
need and advisability OF. constructing a
system OF filters for purifying the wa
ter supply OF the. city. and what in theii.
opinion is the best method of filtration
for the city. and TO request the commis-
soner OF public works to furnish plans
and estimates, begs leave 10 submit the
following report:
Your committee have taken careful con-
sidcration and they are satisfied that
good system for fitering our water Is alb
solutely needed. and we advise that the
city council take the necessary action
for installing a suitable system Of fltra-
tion without any unnecessary ce,ay. We
haze held several meetings in the coun-
ell chamber. all OF winch have been ad-
vertised for public hearings, so as to
give all parties. interested an opportunity
to be heard. relative to the different
methods of iltering and purifying the
city water.
The natural and mechanical systems of
filtration were freely discussed at these
meetings and IL was admitted by the
al II l..xfl hat tl,A mar
centage OF bacteria removed was sub
stantially the same in the best types OF
either system. While the mechanical fl
ters must use coagulants. the natural
filters accomplished the very best re-
suits by slow sand filtration without the
use OF coaguants. AS TO the value and
efficiency OF slow filtration. through
sand. for purifying water for domestic
use. II has been known for a very long
period. D.
a SUCCESSFUL PROCESS.
There can be no question as TO the
satisfactory result of treating Pawtuxet
water by such process. We believe slow
sand filtration would prove more simple
and more endurabe and could be main
tanned at a much less annual expense
The cost TO erect the mechanical system.
ready for operation, Is estimated al $l7S.-
600 for wood tanks and Si9o. 600 for con-
crete. the estimate of the city engineer
presented by the commits ssioner OF public
works. for slow sand filtration is S225, ,o00
for a suitable plant 10 filter from COO
TO 20.cpo.ooo gallons per day. While the
first cost of low filtration may exceed
that of the mechanical. your committee
reel that our citizens are entitled to
have the system installed that Is unques-
tlonably the best. so far as the public
health Is concerned: the slow sand .ys-
TEN Is earnestly recommended by a very
large number of practicinS physicians in
this city.
Your committee desired 10 gee some
OF the best systems OF fltratlon. and
for that purpose visited the mechanical
plants OF East Providence and Bath or
East Albany. also the natural or slow
sand filtration plant at Albany. The me-
'chanical system operated at East Provi-
dence uses upon on average of about one
grain OF sulphate of alumina (or alum
per gallon which at SIS per 100 pounds
would cost $1.& per million gallons OF IL
tered water, while the Eas, Alblny me-
chanical alter was using about double
that quantity at the time your committee
visited that plant. at cost of say So 20
per million gallons The slow sand a.
tratlcn plant I'm the city OF Albany. on
the opposite side OF the river from the
laet named mechanical filters. has a al
terinR capacity o. lo,vpb,VV Ediionr per
day. and Va put IN operation September.
1899
COST OF MAINTENANCE.
The total cost of maintenance for iO.-
0so 900 gallons filtered water was slS5
per milton, and your committee are sat
isflod that with careful management the
cost OF maintenance for the city Of Provl-
dence sill be very mDcn 1css. Even
based on the cost OF mailtensncc Tor tho
natural filters at Albany. The cost for CO.
agulants at the East Providence is u
per cent moro, and the East Albany me-
chauicoi plant costs about twice as much
for coagulants as n costs for maintenance
OF the natural filters at Albany.
In addition TO the above is tie cost for