The Portland daily press., 1879-09-23
GRANITE SLAB
With IRON PLATE

A rectangular excavation is made Just below
the outer portion of the sidewalk; the walls
and bottom are built of brick; the top is COW
cred with granite slab, which has q central
opening large enough to admit man; COM
munication is made at one side above with the
gutter and guarded with an iron grating; and
the floor is placed somewhat below the opening
of the pipe which leads to the sewer, forming
a catch-pit in which the substances that are
brought in from the street may be deposited
instead of going into the sewer. The advan-
tage of this arrangement consists III the ease
and inexpensiveneSS with which the collected
matters may be removed from this cavity,
which is readily reached from the sidewalk, as
compared with the difficulty and great cost OF
taking the same from the sewer. Now 1t VIII
be seen that anything which enters the sewer
from this culvert must pass up through tne
bend in the pipe; and, if water stands IN the
pit a little above the level of the mouth OF the
pipe. an obstacle will be offered to the passage
of the gases from the sewer into the culvert,
and stench-trap or water-valve IS formed.
Theoretically the plan is good, and practically
it will work very well, if proper care Is taken
of the apparatus. If, however, the culvert Is
left to itself, it soon ceases to fulfill its office,
not only in preventing the downward passage
of dirt and the upward passage OF foul gases,
but also in affording a chance Tor the street
wash to reach the sewer For example, III a
very heavy storm so much sand may De swept
into the cuvert as to fill the catch-pit up to the
mouth of the pipe, save only for little aper-
ture sufficient to admit the passage OF a small
stream of water. Suppose, now, that TINS
opening gets clogged with gravel and SUCKS
and stones, which fall in accidentally from
the street. or are thrown in by playful children,
who are fond of amusing themselves with the
splash of the water which they cannot see; the
next time a rain storm comes the modern cul-
vert is of no account, excepting ohly Ior its
CAPACITY for holding certain number Oh par
rels of water; it is not to be compared III use
Al, L. al focbf -
ALWAYS seryiceable for the one purpose ior
which it was made Or suppose a drouth 10
come on and allow the water 10 eVaporate
until it has sunk below the mouth OF the pipe;
nothing then can hinder the emergenee OIL the
filthy emanations from the sewer. t1nally,
suppose the catch-pit to be filled nearly up TO
the pipe, and violent and prolonged rush OF
water to take place into the culvert; it will be
evident that the sand will be greatly stirred
ND. and that, in the rapid current OF water
into the sewer very large amount ol soiiu
material will go with 1t.
We have inspected nearly two hundred Oh
the culyerts, examining almost all on the nortn-
ern slope of the city, and great many on tne
southern slope. 1t seemed unnecessary 10
view a larger number, as, after seeing lew
score. the rest displayed simply repetltions OF
the same few conditions. About one-third OF
these culverts we found to be OF the old style,
incapable of thorough inspection without re-
moving the stone slabs from the top; but we
clean and unobstEucted in all cases. The
smell Of sewer-gas was naturally very evident.
In another third there was enough water TO
constitute a trap for each, but in all the water
was positively vile, and in most 1T was nauseat-
ingly fetd. The reasons for this state OF the
liquid are perfectly apparent. In the hrss
place. the water is never renewed except by
accident as when rain falls, and 1t is inten-
tionallv removed only about once III three
months. The wash of the streets always CON
tains large amount OF organic nltn, sCcn as
ordure from animals, small earcasses, vegetable
refuse, and so forth; and these, IN the course
of time. are more or less perfectly dissolved IN
the water, which, often standing undisturbed
for weeks becomes saturated with the liquid
and Gaseous products of decomposition. Then,
in the second place, the eff1uvia from the
sewer permeate the water which con-
stitutes the valve, rapidly spread through
the entire volume, and escape from
the surface to the atmosphere above.
In addition to these circumstances, we must
note that not a few people, either supposing
that whatever is put into a culvert goes at
once into the sewer, or wilfully disregardlnS
the known fact that modern culvert Is mace
to retain a certain amount OF solld ana hqulu
matter, make practice Of turning INTO the
gully whatever waste they can most conven-
ientiy get out of the way in this manner. Thus
it happens that the catch-pits are the recepta-
cles of a great deal of spoiled brine and other
refuse from shops of various kinds, not to men-
tion matters of much more offensive ana IN
furious character. Thus trap made OF water
which has stood in the gully fora long time is
really worse than none at all; for it not only
lets the sewer gases through, but II auds 70
them emanations from the putrid hith "ith
which it is loaded. ..,.-..,..
The remaining third of the culverts examln-
cd were either entirely empty, or contained not
enough water to trap them, or were filled with 1t
sand up to or above the point marked A IN the
diagram The emptiness of some is accounted
for by the fact that they had recently been
cleaned out; and, as it is nobody's business to
see that clean water is put into the culvert az
ter the sand and foul water have been remov-
ed, the exhalations from the sewer come into
the street without let or hindrance. Evapora-
ton of the water, or the smallness of the ram
fall since the last emptying, explains the con-
ditons of those which had some water out not
the obstruction Of the pipe with sand; One, at
least, was found filed up even with the gutter;
CONTINUED on FOURTH PAGE.