Los Angeles daily herald., 1876-02-26

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The project of submerged dam to
be constructed in the Los Angeles
river above the city is the first scien-
tific effort made toward securing du-
rable and satisfactory system Of water
supply for irrigation in Los Angeles.
The plan was originated and developed
by Capt. .Kelleher, City Surveyor, some
six months ago, and in November last
the resolution of the Council giving
plans and specifications for the work
was published. 1t takes long time
to conform to the requirements of law
in Los Angeles in any public enter
prise, and the affair was not brought
to the beginning sof its end until
Thursday February I7th, when bids
were submitted by several contractors
for building the dam, and the work
was awarded to Messrs. Gay, Eggles
and Greenwood for the round sum of
$29,6l6. Previous to this time, how
ever, the plans of Capt. Kelleher had
been put to every possible test to
prove their practicability and sound
ness. They were examined by Com
mittees of the Council and boards of
engineers, with the result Of finding a
hearty approval in each instance.
Other plans were also submitted, but
those of Capt. Kelleher alone stood
the test.
This subject very nearly concerns
every Taxpayer in the city of Los An
| geles, and Is in one sense the key to
our future prosperity. We shall there
fore make no apology for devoting
considerable space to the considera-
ton of a matter of so much Importance.
The dam is located eight hundred feet
above the railroad bridge, on the line
of the San Fernando road. 1t extends
across the river length Of 800 feet,
joining steep banks on either side.
The specifications provide that"Across
the bed Of the river at the above
named point there shall be two rows
of Oregon pine piles driven parallel
and sixteen feet apart; the piles to be
Of the best quality of timber, six inch
es thick and at least nine inches wide,
and Of sufficient length to reach the
bedrock. In driving the piles care
must be taken to point and drive them
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joints. The space between the piles
is to be excavated to the bedrock and
cleared of all sand, gravel, rocks,
clay, etc. AS the excavation pro-
crosses the piles are to be Sc
curely braced latitudinally and
longitudinally, and to be firmly
bolted. When sufficient amount of
material between the rows of piles
shall be removed, there shall be con-
structed wall of concrete and clay in
the following manner: In the,bottom
of the excavation, on bed rock, there
shall be spread layer OF concrete four
feet thick; from this as foundation
there shall be wall of concrete and
clay carried up to within two feet of
the surface of the water at its lowest
Summer level. The center or core of
the wall shall bt composed of puddle
clay eight feet thick; and the facings,
| (thOse portions next the piles) shall be
of concrete four feet thick. From
point two feet below Summer water
level there shall be wall of masonry
carried up five feet high at the breast,
and falling by loping offsets to two
feet high in the rear At intervals of
twenty feet in the masonry there
shall be openings ten feet wide and
three feet high, into which shall be
fitted good substantial redwood gates,
firmly bound with iron. At a point
near the West end Of the dam there
shall be an opening, or TUNNEL, thirty
feet wide, five feet high, and sixteen
feet deep, aud connecting with the
Main zanja The walls of the tunnel
| shall be of solid masOnry.U
So much for the official specifica-
tions, which, perhaps, require some
explanation before comprehensive
idea of the work may be arrived at.
The dam as it is represented in the
plan presents much the appearance of
an ancient parapet with alternating
embraZures and embattlements-the
former the gates, and the latter the
columns of masonry standing be-
tween. There will be from twelve to
fifteen gates and as many columns of
masonry. These gates are to be low
cred and raised by means of crank and
ratchet. The columns of masonry are
to be protected on the upper side by
heavy facings of plank formed in the
shape of ". These facings will turn
the drift into the openings and obvi-
ate all difficulty from accumulations
above the dam. The tunnel which
leads from the dam to the main zanja,
and through which the city's supply
of water will pass, is provided with
heavy gates similar to those already
described and by them the water can
be shut off from the city at will. This
will prevent the periodical destruction
of the main zanja or toma as it has here
tofore been with each heavy fall of
rain. When completed the dam is ca
pable of holding above its wall, one
hundred million gallons of water.
With this accumulation there need
never be lack OF sufficient to fill
every ditch in our entire system of
zanjas. Summer and Winter, wet
season and dry, the supply will be un-
changed. Besides answering our pres
ent demands for irrigating purposes,
the system here inaugurated is capa-
BILE Of enlargement to answer future
requirements, and in time may be of
service for supplying water for other
purposes than Irrigation. Touching
upon this subject, Captain Kelleher In
his report to the Council on the Goth
Of July, 1875, stated, "This point be-
ing at higher level would admit OF
the construction of a reservoir capa-
BILE of supplying the greater portion of
the city with water for domestic, as
well as for irrigable purposes, the ele-
vaton at the point being at water
line q feet above the highest point on
Main street." We will look forward
to the completion of this important
work, as step gained in the lasting
advancement of our city, and a work