Los Angeles daily herald., 1890-01-02

cubic feet per second, (about 525 miners
ng the sewage TO be 1S 600, and the water sup.
ply per capita to be lis gallons then the sub
soii or ground water would be about 90 per
head per day. The. present sewer. however.
drains large area OF low ground, and receives
much more sub,soil water than would enter in
many other parts of the proposed system.
For the purpose OF estimating the capacity OF
works we have assumed that the sewage equals
but n hundred gallons per head per day. which
i'm plies that the greatest possible care must be
exercised in the construction not only OF the
new sewers, including all branches and later.
sewers, so that they will be rendered water
tight, aud that the soil water may not take the
place of the foul water, for the removal and
publication Of which the proposed outfsll and
disposal works are to be built. Therefore, to
repeat the most careful and most complete
plans may be frustrated by careless eonstruc-
in any way and assisted only by efficient in
spectors OF the highest integrity, is absolutely
The estimates of cost hereinafter presented
are based upon the requirements of firstclass
work throug hout, and upon the demands for
amount OF sewage equal to 20, OOO, 900 gallons,
with a maximum flow at the rate OF ~ OOO,oOV
gallons The excayation and back I'll ing TO-
cents per cubic yard, and TWENTY-FIVE dollars
were allowed for one Thousand bricks laid in
stroEg mortar of English Portland cement.
The castiron ontfall into the ocean is estima..
ted to cost $50, 900 and $4,000 were assumed
to cover the expenses for the purchase OF rights
of way and the necessary ocean frontage
The commission have considered and pre-.
pared estimates for all practicable routes to the
ocean for which data had been gathered.
COST OF DISPOSAL INTO THE OCEAN.
The outfall sewage should extend about 900
feet from the shore into thirty-fve feet Of
water, aud consist of two pipes each three feet
in diameter. These pipes may either be laid
on the bottom ard cove red with riprap, or laid
in trench dredged five feet deep and covered
with sand, in order to make them safe from
the action of waves. At the outlet the pipe
be nons nd Sa sR feet
| heavy riprap or concrete masonry. For the
present il would be necessary to lay only one
cause IN insufficient Velocity and deposits.
Before the sewage is allowed to enter the
l ocean it should be thoroughly screened, and
! the solids burned in a furnace. The cleaning
of the screens and the destruction of the
catchings should be constantly attended to.
which would require continual attendance.
The screens, the machinery for lifting them.
| the furnace and coalshed, should be inclosed
| in one building, which is to be erected over the
$1,000.
The first route to the ocean. considered, ue-
| gins at the southwest corner of the city and
| reaches the Los Angeles river In sOutheasterly
| direction in about five miles, whence 1t fol-
lows the river and finally discharges into the
Long sss tne a raus OF Rey
at ST ,o35 300
| Inc second route DcSlnB at tnB SOuluWebI COT-
ner OF the city and rea hes the ocean via the
Centinela ranch, which we call the Centinela
route. Its total length is 81, 900 feet: The cost
is estimated at $7S7,4o0. This route had to be
changed on account of the objections made BY
the town OF Inglewood, from the one originally
proposed In consequence thereof the present
the former one.
The third and last route begins at the south
: west corner of the city and reaches the ocean
via the Ballona rancho, which We desig nate as
} the Ballona route Its total length is 6S, 200
) feet and the cost is estimated at $696,775
COST OF DISPOSAL BY LAND PURIFIcATIoN.
In the following estimates it is assumed that
the city is obliged to dispose OF the sewage for
: on land through intermittent filtration, before
1t is permitted to run to waste This could either
, be accomplished near the river on land lying
about three miles south of the southern city
limits, on lands situated about one and three.
} quarter miles south Of the Bsllona station.
For this purpose the city would have to own
i. ebout 500 acres of sandy land, prepared 10 re-.
ceive from 10000 to 10000 gallons per day per
acre, or about eight times as much as at present
used by the South Side Irrigation Company.
This land would in summer be irrigated and
cultivated In the same manner any other
land. but during the wet season it would have
to be held in readiness to take every drop of
) sewage brought to it by our outfall sewer. The
!, raising of crops during this period would be
secondary consideration.
With proper management the effluent water
could be safely turned into the river, or into
Ballona creek, not only without creating nut
. the river water itkef.
First Filtration grounds near river.
800 acres of sandy land at $3.50 per
Preparation Of land. sub draining, etc. 400 900
Outfall sewer, feet diameter, 26, 500
feet from southwest corner of the
|, Buildings, screens, furnace etc ....... 5000
Total cost st..................... E. $735 400
Second. Filtration grounds south OF Ballons
station.
800 acres of sandy land at $3.50 an
P .eparation of the same at $500 per
outfall sewer. feet drain, ~, 900
Buildings, screens, furnaces, etc.. 5000
Total cost st.-...............,....... 1856 600
Third-Flltration at both of the above places.
, The peculiar Topography OF the city In hav-
J ing ridge between the river and the western
! boundary suggested division OF the sewage
and its diversion in two directions ten feet
per second going to the river station, and
twenty cubic feet 10 the Ballona route station.
BY TINS ARRANGEMENT the interior system
would cost about $50, 900 less. The estimated
cost Is:
J Purchase and preparation of land 5 $50, 900
Outfall to river, 33 inches in dame
| Ter, lO,oOO feet. Observation-Disclosures. $4,000
Outfall TO Ballona route station A.. 0'~
600 feet, circular, 42 inches di-
Buildings, screens, furnaces. ETC., ior 0'O
two stations. ........................ 1900
$929 600
c Less saving on interior system $4,000
Total cost ....................-....$ us, 900
, COST OF DISPOSAL BY CHEMICAL PRECIPITATION.
, In place OF land disposal 1t ia possible to
, purify the sewage at either of the aforesaid
, points by chemical precipitation according to
methods mentioned heretofore.
Tne effiuent can be safely put into either
. Water course. but 1t would not be safe to use
, the water thereafter for domestic purposes In
pie residing below the precipitation station
should be supplied with pure water by the citv