The sun. [volume] (New York [N.Y.]) 1833-1916, 1890-05-18
HoRCEsTER,s SEWERAGE TEST.
Tho Method OF Chemical Pre- cIpitation to
DO Tried on ii Large Scale.

From the Boston Transcript
BY m act Of the Legislature of Massachu-
the approval Of tho bin. to remove from its
sewage before 1t is DISCHARGED into the Black
stone lHver the offensive and polluting proper
ties and substances there n. 50 that after its
discharge into the river directly or through
its tributares.At shall not create nuisance
or endanger tho nublc health. 1t was pro-
yided in the act that the city should not be
limited TO any particuInr system for the purill:
on the 25th OF June following its ENACTMENT,
md consequently the four years OF grace
given In the city in which to decide upOn some
system and prepnre tho same are Tearing a
close. but before he expiration OF the statu-
tory time tho city will have In operation =, q
believed. will 20 purify its sewage that the
eftluent therefrom will contain nothing to pol
Lutte the waters OF the Blackstone. The. system
adopted by the city isithat known rs chemical
precipitation, and must for a time BIO largely
IN the nature Of an eYperiment as would also
DO the case II any other plan Tor disposal Of
sewnGe were adopted other than that OF a nat
ural watercoqrse. This system was accepted
OF the question in its every phase and bearing.
as promising he pest results at a smaller cost
OF construction than that OF broad irrigation
or downward Intermittent filtration.
As natural circumstance. the publication
works are located Just below QuinsiGanIonl
close by the Blackstone River. and within a
stones throW OF the PToytdence and Worcester
S Of Is
that is. the storm and house drainage all How
into one central outfall, which In Morcestor's
In the easterlv Part Of the city and emptying
into the Blackstone near the Washburn-
T6 Seh act M mafs it plainly manes
that diverging sewer must be made: and In
May. 1858 this work Vas begun, and carried to
than 5000 feot long, and In its course passes
under the bod of tho Blackstone River under
works. ana tunnels the Providence and Worces-
ter Railroad, It IS forty.two inches in
This conduit Is called the outiall sewer, and a
street abo.e it las been christcnel 0utlalI
sewage is but 3.5OO,ODO to 4.0O4OOO gallons
IN twenty four hours. 1t will be observed that
view 10 the future growth of the. city, and tho
same is true OF much that pertains to the new
sewage puriGGau,n plant, -
OF brick chambers for gates and screens. The
screen chambers are butt in duplicate. so that
while ono is being cleaned OF bulky OBJECTS.
such as dead dogs. cats, and tin cans. the sew
age may flow Through tho other. From tho
screen cham bers the sewage pHs7eS through Il
channel to SIX tanks placed parallel 10 each
other and three on II side. These tanks arc
made, OF brick AMI stone laid IL cement with
outside and division walls 3is feet thick and
cApped with q Iaynr OF c2nGlcte, Each tank
is G6.GO feet wide and 100 feet long ia the
clear, each with capacty :, OF 45O,0oO
gallons They have concrete floors slop-
ing to central channel. Between the two
sections of tanks ~ first drain built OF
brick laid in cement. Above this drain is
tunnel. in which is, placed an lo-lnch cemont
pipe with laterals OF same size extend
Ing into each tank. the open surface ao"y99
rs 1t Is three feet below tho cap o the tank
wal 8 1t lotms on independent channel, over
1pective tanks. The arrangement of the tanks
Is such that the savage can he Kept In constant
how, when its treatment becomes continuous.
% ~ can remain ma gnies!G.ent state when ITS
treatment Is called intermittent
The, continuous process VIII first bo tried.
N which case. tho ellucnt., as tho puril ed sew;
lGe is called. il discharged 0y"r u weir located
II the end of the SIKH tGuk, and then down u
par stone stcps into an eliuent channel and
ermittont pro, e~s. TIN o!llucnt VIII pass
through the Iire 70 tho channel. Mhep'it,is
.hllol sludEo from u tank the sewage passes
through the pipe. no matter "La' tho process |
por cen. water. flows by means OF gate into |
tho contra sludgo drain aud hen into n we'll |
.9n ieet IN width and o! the same depih. From |
IN a tract # land. VIII re. 'oI tho present. at |
east, it will 10 p!uughcd under
lose to the screening rhamhers II two-stOry ,
'rame building mas nUrn % ecied aud this con |
-hlhs the nollor; "nEl Q, and grinding and mix |
,iSaes Zine and ~. snIDhate 6f IAN aIum ot r aro
Tie Ghemic4l- II Is proposed to use, in the pro-
portion 81 six lart, of !he first t. four Of tho !
70 pay for limo Is $3.50 lon aud Slj Tor tho
llumlnit, For every l,NOl.oO0 gallons oil sow I
'so l,"u hp4hu7 OF mo Trerlilia,o, IL r. cX-
used in tho miXint! Of the chemicals. anil tho
mixture phSsc- rom the mi eng tanks into tho |
10 the urcrlnitR' ipu tank.
lhennur" prci ltni plRot ant All that .
n"r'h'h more u Is boon constructed b. tho
Morre ter ever hcparlmeu1. under u q dlrcr.
lion Of It's 6uperlg'endeAt. Mr. nIriIard hos
who Is also a skilled nnu eNprrieuCed engineer /
Ths total cost Of construction and incidentais
10 100000, and the annual expense OF maiute-
nance and operating is estimated At from
cost Of construction.