Middlebury register. (Middlebury, Vt.) 1886-1937, 1894-07-20

ii'f -
Total Of sewers down Seminary, etc.
ana down Washington, etc......... S2224 81
EXTRACTS FROM MR.. ~wEesTER's RE-
PORT.
Before giving you my option con
ceIi.ins the requirements vi yuur Village
with respect to a system of sewerage
wish to briefly call your attention to the
principles which are now GENERALLY
recognized as necessary for an economi-
cal and proper system of sewers, and
which ensure the least expense of main
tenance and repairs and the most eff
cient success in operation.
BY the way of introduction, it NAV be
observed that the purpose of a complete
sewerage system is twO-fold =
First: To collect and convey to n SAT e
point of disposal all of the house drain
aye and water contaminated by house
hold and other organic filth. This con-
taminated water is known as sewage.
This object is effected by a system of
underground %conduits, known as a sys-
TEN of sewers.
Second To dispose of the sewage in a
manner to render it innOcuous and harm
less and remove the filth contained in it.
In other words, to restore to a state of
purity the water which has been con-
taminated by organic filth.
In addition to these two main mr.
poses, a complete sewerage system also
provides for the removal of storm water
and for carrying off ground water.
thereby drying out the soil and remov-
ing the danger of wet cellars and I'M
healthy swamps. For the village of
M~lddlebury, the consideration of sewers
for storm water and ground water is at
! tApaentf - .,l ,
for your consideration a sewerage svs-
TEN to remove house sewerage only and
such additional storm water as NAV
come from the roofs of buildings. and
which may serve to assist in flushing
the sewers and keeping them clean. For
the present, it would be we'll to allow as
many houses as desire to discharge their
roof water into the sewers proposed.
In the future, as the capacity of the
sewers becOmes more severely taxed
with house drainage, it will be necessary
to control the collection of roof water.
or to throttle the connections, 10 limit
the volume of storm flow to the service
of the sewers.
1t will also be unnecessary at present
to consider a means of purifying the col
lected sewage before dischaIging into
Otter creek but it should not be lost
sight of, in designing the system of
sewerage, that at no very remote day it
may be desirable and necessary to purify
the sewage, in part at least. before per-
hitting it to discharge into Otter creek.
The question of publication is being
seriously agitated in many places, and
the indications are that before many
years the present custom of discharging
raw sewage into streams and water.
InOnrEpG nGnppiullV thncn frop, Y-h;.I,
water supplies of other towns are de-
rived, will be prohibited by law. 1t is
therefore eXpedient to so plan the svs-
TEN of sewers as to permit of the intro
duction of a means of purifying in the
future. 1t is good policy to make the
plan complete ard far reaching, but to
execute only such part of it at present
as the immediate requirements of the
community demand. Accepting that for
the present the sewerage may be dis
charged INTO Otter creek, some distance
below the falls, without immediate dam
ger, chief attention should be directed to
seeing that the system of sewers is
properly designed and built.
Experience and practical observation
have demonstrated that the following
principles are essential requirements for
success:
l. All lengths of sewers must be laid
in true right lines and with continuous
grades between manholes. A light
burning at any manhole must be able to
be seen at the next. This ensure
proper construction and permits ready
inspection and "A speedy location and re-
mOval of stoppages, to which all sewers
are liable.
,. Changes of direction in line and
of the degree of slope or gradient of
Sc Ners must be made at marholes only.
3. ManhOles must be built or pr0vid
ed for at all functions of sewers, at all
changes in direction of alignment or Of
gradient. The distance between man
holes should not exceed 1870 feet.
1. At the head or dead end" of all
sewers flush tanks must be provided and
connected with the water supply pipes,
and arranged to discharge about 2JC
gallons a day from each flush tank.
y. The fall or gradient of the sewers
should be Such as to give, when run
ming full or half full, a velocity of flow not
less than 3 feet per second and not more
than 5 feet per second. 70 insure this.
the gradient and volume OF flow over
each element of the sewerage SYSTEM
must be carefully calculated. 1t i.
therefore essential that a survey be made
Ol me area TO he drained and levels
taken at all intersections of streets and
all marked changes of grade IN the sur
face, so that profles can be prepared
along the lines of proposed sewers. on
which the proposed line of can be
carefully plotted, and which, in con
struction, should be accurately followed.
1t VIII therefore be essential, before PIE
pairing Il complete system OF sewers and
profiles. to make a level survey of the
nature | have above described.
&. 1t is important that the materials
employed IN constructing the sewers.
and the method of work, be under the
direct supervision of "A competent and
experienced Inspector, acting under adj
vice of an engineer in charge of the
work