Sacramento daily record-union., 1881-07-12
THE DEBRIS DAMS.
OFFICIAL INSPECTION rs TO THEIR
PRESENT CONDITION.
The Number and Nature of the Breaks-
The willows Growing aud Dams
Becoming Thicket.

and Bear river debris dams, which they in
spected with view to determine their pres
e1t condition and the effects which the por-
tions remaining had produced in the
direction OF retaining the sand and gravel
as anticipated by the Engineers and Drainage
Commission at the time Of their construction.
The party went up TO Marysville on Friday
and left there early on Saturday morning,
going up the south side of the Yuba TO the
dam, where they were met by Commissioner
Sesrles and others. The inspecting members
of the company were provided With rubber
boots to enable then, to 60 over the structure
and for this purpose ford reasonable Gspshs
Of slickens aad water.
PRESENT CONDITION OF YUBA DAM.
MI parts of the YHba dam were thor
oughly examined, aud it was found to be in
| far better condition than has been reported
or was supposed after the excessive high
waters of the past winter, and the breaks
which occurred so soon after .heir construc-
tion. Commissioner Knox, In answer to
numerous questions propouuded, subsequent
to his return to the city, gave the result Of
their examination as follows: We found two
breaks in the Y2ba dam. One was from 200
to 4G0 feet wide, and about quarter OF
mile from the south end. 1t appears that the
whole structure OF this point has gone out.
About hall 8 mile further on is the other
! break, which Is in the neighborhood Of 700
! feet wide. There are evidences of brush re-
naming at places over tbs break along the bot
( tou. but this cannot be definitely de-
! ternined now as the river is still running
through these nearly the whole widsh.
! The most of the way, however it is only q
| few inches ia depth, but the slickens beneath
is soft and not inviting to an over degree Of
curiosity From this point to near the north
end of the dam no injury mas been done
whatever, and 90 far as can be seen the crest
| has not settled in the least out of range. The
/ top Of the dam is covered with heavy DRIFT
| wood, much of which is composed of
LOGS TWO FEET II DIAMETER,
Which have caught upon the. crest and been
lett there as the river fell. just before reach
| ing the north end there Is small settle in
! the brush work, but none is gone, ana be-
yond the buikhead at the end of the dam the
earth embankment adjoining the high ground
| has cut out for space of 200 or 800 feet and
down to the original surface. This was not a
portion of the dam, but a connecting en-
bankment with the high ground outside.
Above the portions of the dam where there
has been no breaks, the sand and gravel is
filed in and retained within two or three
feet of the crest of the dam, and the hight is
apparently continued with ascending grade
as far up as can be seen, with an occasional
small bowlder two or three inches in diameter.
Upon the lower side of the dam the sand is
from four to six feet lower than above.
From Immediately below where the water
pitches over the dam, and down for distance
| of several hundred feet, there has also
been large deposit of debris caused by
the slower movement Of the water, and which
grows less again as the water regains its
velocity.
| Within the dam. where the breaks occurred
of course the sediment which had been filed
in was carried through and into the river
| again below, and channels with sloping sides
are thus formed inside the dam, leading to
| these breaks and extending as far above as
could be seen from the crest. We were in
f0rmed hy man who resides near by that
prior to the breaks in the brpsh-woik the
water above the dam presented the appearance
of lake, being nearly still, and the accumu-
Iation Of sediment apparently even the whole
way across.
TEE DAM \ GLOWING rHTcKET
The dam from one end TO the other. in-
Guiding the mattresses below, where not
covered TOO deep with saud, il now a dense
growth of willow, excspt at the breaks This
willow growth has sprouted from the logs and
/ brush of which the dam is composed, and
| presents the appearance of green ridge, ex-
| tending from one bank of the river to the
other, and is from three 20 four feet in hight.
New roots are thus forming. and the entire
structure viii soon become formidable from
this new growth, and indestruetible 10 any
action of floods, and by slowing the water, if
the CID breaks are repaired, viii stop the
sediment and cause building up and raising
OF the crest Of the dam to quite an extent
without artificial means. This is rs Captain
( Eads and the engineers stated would be the
case. and but for the untoward circumstances
which caused the breaks, the dam would now
/ be growing into an indestru3tibe barrier the
entire distance between the high lands upon
either side OF the river.
| The channel OF the river at this point for
! the past few years has been close to the north
side, along the iIarysyille levee or Browns
! grade; but the main break near the center
! Of the dam has changed this so that it now
runs through about the center Of the river
| fat
C0STIDENoE ~ THE DAN.
Colonel Mendell and his assistant were
highly pleased viii. the portions of the dam
which remains intact, and are extremely
anxious to have the breaks repaired, being
entirely confident that by so doing ths ex-
perience OF another winter will demonstrate
thas the original opinion of the engineers,
that these structures could be made to per
form the Office for which they were intended.
was correct. So confident Is Colonel Mendeil
upon this point, that should the Drainage Act
he declared by the Supreme Court to be un-
constitutional he would, if be had Govern
Tnent money q. his disposal, repair these
dams at once 60 prove their success.
The party afterwards made careful exam
one side OF the river and down upon the
other, for the purpose of determining the
extent Of filing which had taken place as ex-
tending up the river. Before The dam was
built the State Engineer had cross-section
lines run across the Tiver every two Thousand
feet for three and half miles above, and
marked by stakes aud bank marks on each
side of the river, so that the amoant Of fill
ing which should take place could be scCu.
rately ascertained. Surveyors are now EN-.
ployed upon both sides of the river reviewing
these cross-sectioa lines, which will furnish
accurate information upon the subject v her
the surveys and deductions are completed.
THE BEaR RIVER DAM.
The next day we made a tip to The Bear
river dam and gave it a careful inspection the
entire length. We found in it two breaks
One near the north end is from 800 to 40t
feet long, and the other is about 100 feet long
an / near the south end. Between those two
breaks are settles in three or four piac s.
where | should think the crest is two or three
feet below its original alignment, and for a
distance of perhaps 100 feet or so in place
The structure at these places. however, i
perfectly intact, and only settled out of ine
perpendicularly. This dam is also found tc
be growing thick mat of young willows
the entire length. except at the breaks men
toned. the growth being even denser anc
greater than that upon the Iuba. My I'M
pressions are that not SO much sand anc
gravel deposit has been made in this dam as
on the other river, but very large amount
is 20 be seen above, and is filed in to consid
erable depth. The surveyors, now upon ths
Yuba, will also make similar survey above
the Bear-river dam. They will conclude tht
work and computations within about ten days
We found that Mr. 0'Brien, Superintendent
OF the mines at Smartsville, is now building
brush dams at the mouths OF some OF tn:
ravines to hold back the tailings, SO far a
possible, and prevent injury below, shonlc
the iBjunctioDs be dissolved so that the mine
can bo worked. 1t was also stated tha
owners of other mines were moving in thI
same direction, with view to prevent, i
possible, injury to the country below, anC
still continue the working OF the mines.
DEBRIS DAMS A NECESSITY.
Question-Suppose the Injunction suit
nowlpending, or Others which may be brought