Sacramento daily record-union. [volume] (Sacramento [Calif.]) 1875-1891, 1880-11-11
IMPOUNDING EXPERIMENT
A Crucial Test of Engineering
Theories.
The Yuba Dam Completed and the
River Turned into the Reservoir.
s Detailed Description of the Splendid
Structures Erected by the Drain
age Commission
To Check The Flow or Mining Detritus
into the Nayigable Rivers.

into the Navigable Rivers.
There can be no doubt but that the gravel sand
and much Ct the finer sediment brought down by
these rivers be deposited almost wherever it is
desired to place them within the territory now
covered BY the sediments and held there perma-
nently by brush work only, to hight varying from
to twenty feet in addition to the depth Oh
detritus already in place.
In these words the State Engineer of Cali
fornia expressed himself to the Board of Di-
rectors of Drainage District No. in July
last He had reference to the Yuba and
Bear rivers, and was discussing plan TO
check the wave of detritus and debris which
is approaching this part of the Sacramento
valley like great wave. filling up the rivers
and threatening to literally blot out and rem
der uninhabitable one Of the most populous
and fruitful of all the sections of the State.
Indeed, in the Yuba river alone the annual
deposit of this mining slum is found by en-
gineers to be no less than
TWENTY THREE MILLION CUBIC YARDS.
The primary object of the State in estab-
fishing drainage directories and systems was,
so far as this valley is concerned, to preserve
and improve the channels of the main drains
or navigable streams, which are great natural
free highways-the heritage of all the people
of the State. the object was not to restore
the channels of their tributaries, which
originally receive matter that is washed into
the larger rivers, but to withhold in these
tributaries all the matter that can possibly
be held back, and thus enable the rivers be-
low to be secured out and secured In their
channels and restored SO far as can be. to
their original nayigable condition and carry
ing-capacity, making remote tie danger from
inundation, giving permanency to the thous-
ands of homes in the great valley, and bring
ing under more general culture its splendid
agricultural lands The Importance of such
a work has never been questioned; its value
to the entire State is beyond cavil; the in
terest of all the people of the commonwealth
in the work is as great as in any other
work which tends to populate the State,
increase its homes and its wealth, develop its
resources and divide the burdens of govern
ment.
IT WAS THIS GENERAL INTEREST
Of all in great work which led the RECORD.
UNION to make detail from its force to ex
anime the restraining dam just completed on
the Yuba river, above Marysville, and to
direct such plain and simple description of
it, Invested of the mask Of technical engineer
ing terms, as should give the general reader
fair idea of what has been done. This task is
not without difficulty, for while the visitor to
the works takes in the whole situation at a
glance, and comes away a thorough convert
to the theory of the plans, and a firm believer
in their ultimate success, the reader must give
the closest attention to the text and endeavor
to picture the scene as it is sketched for him
by the RECORD UNION, whose representative
yesterday visited the works.
The Yuba river debouches into the Feather
river just below the city of Marysville. tits
turgid, rapid, treacherous stream. It was
once deep. clear, and flowed within high
banks, on the plane Of which stood the city
of Marysville. Now the Yuba at high
water is about on level with the city streets,
and sometimes above; the banks have been
obliterated, and the demoralized stream,
aimlessly over a shining bed of sand and yell
low mud cement from one to two miles in
width, and in flood times pours its waters
here aud there over the land as they rush
down its now precipitous and artici6cial bed,
destroying towns and villages, and covering
farms and orchards and agricultural lands
with the gritty sands and the cement.like
slickens, and as one goes up stream he notices
in addition deposits of small pebbles, then
larger ones, then stones as big as ones fist,
and lastly cobbles and rocks as large
as pumpkins. Passing on up the river
bed, broad, sandy and dry, with only
trickling stream in its midst. the
visitor walks over spots where far below
orchards that once dropped their fruity wealth
upon rich alluvial soil. over pasture lands
now twenty feet beneath the mining detritus
and over rich bottom lands now buried in the
everlasting gravel of a sandy avalanche.
Eight and half miles above Marysville the
land on the north side suddenly rises. 1t is
the first roll Of the foothills. Here the hills
lift themselves from the desert of sand
slickens and mud, and their bald tops look
down gloomily upon the river, here two miles
in width-a scene of desolation as far up and
down the stream as the eye can reach. A
few weeks ago all this space was thickly
grown with willows now it is cleared off, the
brush having all been cut, with which to con-
struct
THE RESTRAINING DAM
That one sees now starting from the brow of
the low swell of land on which he stands,
and stretching in direct line southwark two
miles across the sandy bottom, its farther end
being scarcely distinguishable from this point.
Its top is as level as engineering science and
skilled workmen can make it, and it reaches
across the desert waste like great prism laid
upon fat and unobstructed surface. One
realizes now that he has totally miscon -eiyed
the character of this structure; that he has
had no true appreciation of its details, and
when, in common with so many other citi-
zens. lie has expressed the belief that the dam
would amount to no more than its name, that
he spoke as one lacking knowledge Of
the subject, but now ready to confess the
error of his uninstrueted judgment. The
dam consists of BRUSH wire and logs. 1t is
about II, goo feet in length. 1t presents on
its downstream face perpendicular front
from to II feet high, composed of the
Jagged butt ends of countless saplings, small
trees and logs with alternating layers of logs
like stringers and rafters beneath floor On
the up-river side it presents face of gentle
slope from the top to the river bed, composed
of alternate layers of young willow trees cut
in full foliage, laid top down and very thick.
ly, and interspersed by horizontal layers of
heavy logs. On top of these trees is layer
of long logs parallel with the brush and placed
closely together along the entire crown of the
dam. On top of all is sand from two to three
feet in depth, and graded to gentle slope to
meet the river bed. At the base this dam is
from 65 to 20 feet wide.
ON THE DOWN RIVER SIDE
There extends outward for 80 feet bed of
willow mattresses. also covered two feet deep
with sand. These mattresses extend some
six or eight feet beneath the dam itself, and
constitute an apron to prevent the overall Of
water from the lip Of the dam washing out
the earth at the foundation of the structure.
Such, in brief, is the dam, but it is advisable
to describe the method of its construction,
and that it may be clearer rough diagram,
sufficient to indicate what is meant, is intro
dueed:
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