Wichita eagle., 1888-04-21
Can the sewage be delivered at the pro-
posed Outfo1l ysthor,+ r,11poriuoS

4
posed outfall without pumpings
| The flatness of the territory TO be
severed and the slight depth of the river
bed below the general level OF the land
require a careful study into the least
grade which will cause sewage to flow off
in small pipes. The general slope OF the
| ground from which the sewage must be
carried off is very regular, and averages
| from to u inches per 1000 feet. With
| this grade sewers of Is inches in diane
ter and over, when running at least half
| full, give a velocity of at least Is inches
! per second, which Is enough to carry light
sewage matter away and to prevent de-
| post. The Topeka avenue sewer, which
has fall of 12 inches per 1000 feet IS a
sufficient proof to you of this fact For
s inch pipes, which constitute the branches
or laterals, grade of feet to feet Is
necessary to produce cleansing velocity
1t is entirely practicable to obtain these
grades for mains and laterals at
all points between the river and
the creek, down TO the outtall.
| Therefore it is not necessary TO resort to
pumping in order to remove the sewage
| from your city.
1t is true that the above mentioned
grades are only barely enough, and that
an increase. which might be obtained by a
pumping project would be highly desira-
bic; yet there is a circumstance which
makes such project very expensive. tits
| pretty well demonstrated that the entire
city is underlaid with a bed of quicksand
about nine to ten feet below the surface
To build sewers in this bed would entail
cost which is hard to estimate, but which
would certainly be great. 70 make a
| pumping scheme OF any real value 1t
! would be necessary to build the sewers
| into this quicksand for thousands of feet
| 1t would reqaire an annual expense for
| pumping not only the entire quantity OF
sewage, but a good deal of ground water
which would enter the sewers in spite OF
the greatest precaution taken in building.
| The large expense of construction and the
capitalized cost of pumping would to-
gether not be justified by the gain of
greater velocity in the sewers which
pumping system might allow To satisfy
| myself of the existence of this quicksand
| asked your city engineer, Mr.. Mulvey,
kindly, to have holes dug and bored in the
northern, central and southern parts of
the city, and invariably found the running
sand at the stated depth.
The fifth point TO be considered is: What
| system of alignment can be given the sew
erS to obtain the best grades and velocity?
1t makes a great difference in the vel
ocity whether sewer runs half full or
only One-quarter or one-tenth 1ull. The
less water runs in it the slower will be the
speed. Until the city is completely built
up there will not be enough sewage to fill
many of the sewers one-tenth full. 1t is,
therefore very essential to provide at once
such means as may be deemed best for
flushing This can be done by building d
tank at the head of each lateral, fed from
the Waterman and discharged either auto
matically or by hand. 1t can also be done
by having water carts holding some 500 to
!, 900 gallons or more discharging their con-
tents suddenly into a manhole Of
the sewer. Finally it can be
done, if practicable, by allowing
water from some natural stream to enter
the sewers at such times as may be de-
sired In your city the latter scheme is
practicable, as the water of the Arkansas
river may be turned into the sewers at any
point north of Kellogg street, and that of
Chisholm creek at any point north of First
street.
Holding the foregoing points in view,
different systems of alignment may be de
vised | have been shown one made by
Messrs. Rosewater s. Christie, based upon
the use of the Arkansas river fer flushing
the light grade sub-mains and mains and
upon the use of automatic flush tanks for
flushing the lateral sewers Their system
is carefully planned and as far as l see
could not be improved in any OF its essen
tial features, if the above system OF flush
ing is the only one which is available.
But the long lines of laterals at grade of
only 30 feet per 1000 will require very
careful attention to be kept In order. The
slight automatic flush from the
head of the pipes will not be
able to remove deposits after
passing down several hundred feet and the
laterals, as well as some of the sub-mains,
having fall of 10 inches per 200 feet, and
which cannot be flushed from the river,
will have to be flushed and cleaned by
labor. Yet, with the above promise, l see
no better arrangement. If it is practic-
able to obtain the use of water from CHS
holm creek for flushing, different system
of alignment can be established which has
the advantage over the other one that the
grades are somewhat better for the mains
and decidedly better for the laterals.
This other system is shown on the &C
companying map, which has been kindly
prepared for me by the city engineer. The
mains begin at the creek, where a valoe
regulates or shuts off the water. They ex-
tend through the city down to Harry
I'll Al Al. -
Santa Fe railroad, and thence along its
right of way TO the outfall. If levels show
it to be practicable these mains could be
extended on to their courses to the river
instead of being united into one outfall
sewer, and it is possible that such pipes
might be laid at less cost besides having
the advantage that the cost could be
spread over longer time, each main being
built as needed, and that they could be
more rapidly built The mains run on
parallel lines three blocks apart, which
allows the laterals TO be short, and, there
fore to have much better grade than if
the mains were one-half mile apart. AS
shown on the accompanying sketch, the
usual way of running the laterals would
be TO have two blocks draining toward the
south and one block toward the north and
the two united draining east or west one
block into the nearest main
The mains have been drawn in the alleys
1t is the best place TO put them because
the house connections are much shorter
and therefore less expensive to the prop
erty owners. The alleys are discontinued
at Douglas avenue and the sewers are
therefore turned and subsequently, follows
L -
which is also a more economical distribu-