The record-union., 1897-11-06

along its course sewage may be had
for irrigation by anyone desiring to so
use it. Only a part of the city's sew
age is now SO used The aggregate area
| irrigated near Los Angeles is about
3.700 acres.
AT Pasadena about one half of a sew
| age farm of 800 acres is irrigated with
sewage.
AT Fresno the sewage Is spread upon
land live or six miles to the westward
| of that city; so also at Redding a sew
| age farm has been established.
| In connection with every local sew
erage problem this question of disposal
| must be considered, and enough has
been said to indicate that no fear need
! be entertained that the question can
! not be satisfactorily answered. 1t is
| generally assumed that depending upon
| character of soils and subsoils from 200
| to 800 acres per 100000 gallons of
! sewage in "a hours are necessary to
successfully dispose of it when used
Tor irrigation. But these figures are
based upon experience in the East and
in Europe and should only be consid-
cred of value as indicating the result
of the experience in much more Sc
we're climate than that of this coast.
The rate at which sewage may here be
applied to land with satisfactory results
remains yet to be determined
| Elsewhere than in California, and the
exception mught almost be restricted to
San Francisco, it would seem almost
superfiuous to say anything about the
| collection of sewage, but we have
\ IN LIT
and as necessary evil a lack of sys-
tenn In this matter and a haphazard
method of procedure that is really be-
yond comprehension. This statement
applies with full force to this city, in
a much less degree to our other prin-
cipal centers of population, and under
the circumstances 1t may not be amiss
to say a few words on this subject.
| Water carriage of fecal matter with
other waste being accepted as an es-
tablished condition, it becomes neces-
sary to so construct the conduits as
not to poison the air We breathe or the
soil under foot. 1t becomes necessary.
too, to determine whether the conduits
| Tor the sewage are to be made large
enough for rain water as well. or
whether they are to carry only sewage
proper Here again, local conditions
must be we'll considered. 1t is some
times possible to send rainwater over
the surface of the streets in open gut
terWays to an outfall, but often this
cannot be done for the reason that its
volume becomes too great. 1t must then
| De put into subsurface channels. which
not lnfrequently are almost co-exten-
| slVe with the conduit system for sew
age proper. The economy so often
claimed for the separate system Of
sewerage rarely exists; on the contrary.
| When any storm water conduits are
necessary they, in conjunction with the
| sewers proper, may generally be as
sulned TO cost more than sewers for the
comolned flow Of sewage and storm
water.
| 1t must be apparent at once that a
city located like Alameda, which sheds
water, ike ducks back, toward both
sldes, can well be severed on the sepa-
rate system without the use Of anv
storm water sewers, while in nany nor
tlonS or San Francisco the choice lice
only between either a combined sewer
or two complete conduit systems. one
Tor sewage and one for storm water
only
Conduits for storm water only are NOT
common in California, and thew are not
under ordinary circumstances. desir-
aoie' because they would be practically
out of service for long time periods and
"ouio De extremely difficult to keep in a
satisfactory sanitary condition: thew
may De fuily as Objectionable as large
sewers adapted to storm water flow and
usually charged with a flow represent
ing only small fraction Of their capac-
ity.
The leaning Of sanitary engineers at
the present time seems to be toward
small sewers on the combined system
With relief outlets for excessive storm
| waters.
/ NO infiexible rules can be laid down
as TO the best system of collection. but
this system should be determined in
each case by typographical features. eli
matte conditions and the like. not unin-
| fuenced by the predetermined method
Of disposal as well, that which NAV be
adopted as a temporary expedient. as
also that which is ultimately TO be
| adopted.
Whether collected in separate con-
! dults, or by any other system. the sew
age once delivered into conduits must
be carried to the outfall point. Ordi-
narily this is accomplished in whole or
in part by gravity flow. The conduits
unite with each other until finally the
| entire flow from district-which, un-
der certain favorable typographical con-
ditions may embrace an entire town or
city-is in a single main. Often the
flow Of series of main sewers is re-
ceived into what might be termed an
intercepting sewer
Sewers are usually constructed along
street lines, and this fact Is to be taken
into consideration in establishing street
/ grades. The sewers are generally so de-
signed that the sewage flows with suffi-
eient velocity to reach the outfall point
| in SO short a time as not to become
putrescent, and to keep deposits from
accommodating along the lines Of sewers.
All this seems simple enough, and
when sewers are thus constructed, it
would seem an easy matter to secure a
proper ventilation and thorough flush
! ing and to establish adequate systems
! of traDs to prevent flow Of noxious
gases from the sewers into dwellings
| But these simple principles are occa-
sionally ignored to an extent SURPRISING
helief as illustrated in this city, in
| which about one-fourth of the popula-
ton of the State. population large
enough to justify axf-eme sanitary pre-
cautions. is compressed into an area of
/ about 10000 acres. which is traversed
in all directions by conduits built with
| out system and reeking with filth.
For forty years sewers have here
| been constructed without regard to
( l>s 1f