The Morris County chronicle. [volume] (Morristown, N.J.) 1877-1915, 1906-01-02
PLAINFIELD SEWERAGE.


| Inc city OF Plainfield, with a p0pn
lation Of about $1,000, is situated or
the Central Railroad Of New Jersey
twenty-four miles from New Yorl
city A water supply system was in
troduced by private company II
1891, and a sewerage system was con
structed by the city in 1895. Separate
sewers are used for storm water and
sewage, and the sanitary sewers, from
8 to "A inches In diameter, discharge
onto intermittent filtration beds.
The disposal system has been very
bitterly opposed from the first by resi-.
dents in the vicinity of the filter beds,
and this opposition has continued to
the present time. 1t is claimed by the
| directors that the beds are located toe
near their residences, and that this
proximity is depreciating the value Of
all land in the vicinity. They also
claim that the sand in the beds con
tains TOO much fine material to filter
properly, so that the water remains
too long upon the surface. A suit for
$4,000 damage was brought against
the city by the proprietor of a nearby
summer boarding house, but decision
favorable to the city was rendered by
the supreme court on the law points
involved in the case.
Wheni it became necessary, in 1908,
to consider means for charging the
capacity of the disposal plant, the feel
ing against adding more sand filtra-
'tlon beds was very pronounced. JOS
eph 0. Osgood, of New York city was
engaged as consulting engineer, and
after a very thorough consideration of
the experiences and investigations of
other cities in this country and abroad,
he recommended, and the committee
on streets and sewers adopted, the
plan of disposal which is now nearing
completion. This comprises two sep
tic tanks, side by side under one roof,
and a double set of bacterial contact
beds, eight in all, so located that the
works are 200 feet from the nearest
and operated in such man
ner that the sewage does not appear
on the surface until discharged into
Green Brook.
The septic tanks are about 50xl0O
feet each, and feet deep, the water
rising only feet above the bottom.
The sewage is taken from one of the
old gate chambers, and flows continue
0usly through a 15-inch pipe to the
small infsuent chamber, where it may
be diverted to either tank by wooden
gate. The sewage flows downward,
then out into the tank about feet
above the floor and close to The parti-
tion wall between the two tanks. In
front of the outlets are battle walls to
defect the flow and cause the sewage
to move slowly and evenly across the
whole width of the tank to the outlet
of which there are twelve in
each tank, at such a height as to take
out the clearest water, leaving the
sediment below and the thick scum
above.
In this slow passage Through the
length OF the tank "a considerable
part of the organic matter in suspen-
sion is either liquefied OF passes off as
gas. the coarseT particles remaining in
the Sludge with the inorganic sedi-
menNr to be further acted upon by the
bacteria. .
In leaving the tank the water passes
behind weir and over it into
a channel, thence to the first set of
contact beds.
In the septic tank the air and light
are excluded as mach as possible, but
after leaving the tank this effinent is
aerated by passing over the weis in
thin sheet, and by falling into the
channel, the weir and channel extend
ing the full length of each tank, 100
feet in all. They are covered by flag
stones. alternating with wooden re-
covers.
At one end of each tank a Il inch
gas pipe extends through She roOS, the
pipes, having funnel-shaped tops cap
ped with fine brass netting. 1t is ex-
pected that the infiammable gas re-
sulting from the breaking up Of the
matter in the sewage will be
burned at these vents.
The gate houses. and the roof over
the septic tanks are Of wood with tar
and gravel covering I; the gate cham
bers, nnanholes and part of weir wall
ale of brick and blue stone, but all the
construction is of Portland
cement concrete, composed Of one part
Dragon Portland cement, three parts
sharp yellow sand from Amboy, N. j.,
and ave parts crushed trap rock.
The contact beds are in two sets Of
four each, the first set 5x42 feet higher
than the second, each bed being 92xl06
feet in plan and s feet deep. The floor
is 8 inches thick and all walls, except
the centre walls containing pipes, are
one foot in thickness. This light con-
strucJiOn was made possible BY the
fact that the walls are supported on
one side by the stone or Stag Of the
beds and ON the other by the earth,
embankment
fN., tloo oo,oo,.et a fnnr IF oa0ln had