The record-union. [volume] (Sacramento, Calif.) 1891-1903, 1897-04-11

as the shallow river. and the conclu-
sion is not hard to draw.
| 1t will he asked why does not the
Mississippi River deepen itself in its
shallow reaches? The answer seems
} plain, when the reports on the char
acter of the material in the bed of the
stream say that from Cairo to Fort St
| PHILIPPE il is composed of a tenacious
| clay, which does not yield to the i'm
pact of the water.
The second principle above noticed,
therefore, may be enunciated and
crystallized into the following law:
A CRYSTALLIZED LAW.
The depth of river flowing through
an alluvial formation of it's own de-
post will be determined by the volume
of water that may be introduced into
it when confined to normal width.
| The fact that the river is in a tidal
area cuts 70 figure in the ability of the
water to do its work, except that it
rather assists the cleaning of the river
during slack river flow.
THE. SACRAMENTO RIVER
On the Sacramento River, at a point
known as Rio Vista, in the dry season
of the year we have variation of tide
of nearly four feet. In flood time the
variation of the surface of the water
due to tidal influence is but six inches
All that is necessary is that the vol
ume of later in the river shall have
sufficient velocity and momentum to
| force the tidal flow back The fact
| that the depth of the stream is below
low tide line seems to cut but little fig
ure in the flow of river within a til
| dal area. When We consider that the
Mississippi River, with depth of over
160 feet ii front of New Orleans, keeps
its channel maintained, refuses to per-
NIT the tidal flow to interfere in flood
| season, although the elevation of the
| flood water surface is not more than
| twelve feet above tide, giving fall of
! one and Cne-half inches to the mile to
| the Gulf. we must conclude that the
| securing power of this vast body Of
water is maintained in the whole chan
| mel throughout it's whole depth, from
surface to the greatest depth at any
point in the stream. We must con-
! clude that the whole body Of water
| from surface to the bottom moves with
| a certain velocity, which ever resists
| the tendency of earthen matter to re-
| main in the bed of the stream
| ARTIFICIAL MEANS.
| If the bed of the stream is COM
posed of tenacious material. such as
| clay or hardpan, or covered with
coarse gravel, as is the case in the
Mississippi River, then will the stream
cease to deepen, and the improvement
of the bed of such a stream can only
be accomplished by artificial means.
NO MATERIAL OBSTRUCTION.
| The rivers of California in their lower
reaches do not so far as we are in
| formed, present any material obstruc-
ton to the application of the principle
| above recommended for the deepening
| of the streams.
| SAND AND SLICKENS.
! Indeed if we examine the bed of the
Sacramento River from the mouth of
| the Feather to tide water we find the
stream has been filled all the way from
ten to twenty feet since 1S49. This ma
terial consists of sand and slickens
/ which the water will readily remove if
| the stream is made to carry sufficient
water to supply the moving power
| FAVORABLE FOR DRAINAGE.
| The Sacramento Valley could not be
more favorably situated than it is to
supply good drainage. From Iron
Canyon the great catchment area OF a
portion Of the Sierra Nevada Mountains
and the catchment area or watershed of
! the upper Coast Range concentrate
| their mighty waters. which flow to the
mouth of the Feather River practically
sunloaded with slicNens and sand. The
I CT
time give to this flow of water 114,OOO
acres of land over which it spreads and
drops it's sediment. entering again the
main stream at the mouth of the
Feather, prepared to take up the good
work from this point to the bay. What
ever may be the inability of the waters
of the Feather to carry it's load on the
lighter grades Of the Sacramento may,
! by proper care. be supplied by the I'M
! loaded waters Of the upper Sacramento.
1t is we'll to note here an illustration of
this principle
VALUE OF LEVEES.
The Sacramento River from the lower
end of Wood Island to ColinsviIle, a
distance of about sixteen miles. shows
a deepening or erosion since 1878 for a
depth Of from three to five and ten
feet. Why is this so? The only an
sver that we can give is that levees
| have been constructed and maintained
/ to n considefab BILE degree of permanency
along the left bank of the stream, the
river water does not carry SO much silt
as it did in 1878. and the great volume
/ of unloaded water entering the main
/ river through Cache Slough from the
Z oio Basin gives the necessary eroding
power to deepen the river. We also
note that in this portion of the river
wherever we have a normal width.
commensurate with the yolllme OF
water that it must carry during flood
season, the river is deep, has a uniform
channel and has bettered it's water ca
pacity very materially since 1878 On
the contrary, wherever the river has
an abnormal width the river has not
| bettered it's condition. but on the con-
trary has shoaled to some extent The
drainage of the Sacramento Valley.
! therefore, depends upon the retention Of
the waters of her rivers in one deep
channel from their source to their out
let. If this principle cannot be made
to apply to all parts of the streams it
should be compelled to approach as