Sacramento daily record-union. [volume] (Sacramento [Calif.]) 1875-1891, 1881-12-15

&c dsnosited on its way to the Sacramento
rivar But all the sandy material is dropped
oysr and over million times no doubt, the
matters dropping it and afterwards picking it
m AGAIN but the general tendency is for all
tbis material to work its way down into the
| valley. with the exception of the heavy gravel
coming from the lower bench, and the CO.
ment.
Q.-Describe the general characteristics OF
| the drainage area of the American river?
| Witness produced an official copy Of map
from the surveys from the Office If the United
States Surveyor General, showing the gen.
eral characteristic Of the drainage area Of the
American river, and proceeded to describe the
sources of that river. He said that the whole
drainage area is in the shape Of a fan, and
finally the waters are all discharged through
a confined space near Folsom.
@ tby MIR. Wilson, How wide is that pas
sage you refer to near Folsom?
A.-Where the American river escapes
from the mountains, just above Folsom, the
canyon is only 280 feet in width at the ex.
treme high.water mark-or 200. So that all
the floods which are brought down by these
various mountain canyons are confined, as
they escape at this particular point, into a
very narrow compass.
| Q-What is the acreage area OF that water
shed?
/ A.-The entire area is 2, $50 square miles,
and the amount of mountain drainage Is be-
tween 900 and 1000 square miles.
THE CAUSE OF FLOODS.
O.-Describe the cause of the fl ,ods which
occasionally sweep down the American and
other rivers of the State, including the Sacra-
mento?
A.-The foods are generally caused by a
heavy fall of snow in the month of Novem-
Der and early in December on the mountain
sides. That snow will accumulate to depth
of four or five or six or seven feet. 1t is very
soft. ha, not had time to pack as snow does late
in the season on the sides of the Sierra Ne
vada. Generally about Christmas, or little
sooner than that in food Years. warm rains
fall, and continue to fall for some time.
These rains fill up the lower rivers, and
fill them pretty full, and this same rain is
taken up by the snow on the mountain sides
lust as though the snow were a sponge. l
have feen myself eight or ten inches of
warm rain in twenty-four hours, falling upon
the snow, and the snow absorbed nearly all
of it-snow four or five feet deep-and finally
when the snow becomes overwhelmed with
water, when its sponge capacity ceased,
it melts away and comes down at
once. Then in these canyons, like those
on tie Yuba, American and Feather rivers,
| there are torrents, continuous torrents,
pouring down the whole length Of
the mountain sides. A person needs
personal experience to see how rapidly
water can get off the ground as it
does there-it is perfectly marvellous /;
and in the mountain canyons the waters
rise to a very great hight, and come
out in huge masses until they strike
the waters in the valleys, which are
already high, piling upon them, and the re-
suit is great food in the valley. A great
food in Sacramento is only caused when all
the rivers-the American, Bear, Feather and
the upper Sacramento-are flooded, and
their floods unite at the same time ; then the
result is an enormous food, all their waters
reaching Sacramento at about the same time.
| Q.-State whether or not the maximum
| floods are determined or can be fixed by the
amount of rainfall for the year?
A.-The maximum amount of food does
not depend upon the total amount of rainfall
| for the year, because you can have large
! flood like thai of 1881 without very large
amount of rainfall. The food would not coz
tinue so long but still the water in the river,
when it is at its maximum, is much higher
than it would have been with rainfall twice
as great or so per cent. greater.
| Q.-Will the record of rainfall in Sacra-
mento fairly show the general amount Of
precipitation in the Sacramento valley?
| Att does not at ALL 1t certainly will
not, because there might be very heavy
rainfall at Sacramento, and it may be light
in the upper part of the Sacramento valley in
| the same year. | have noticed very great
W ration in the relative amount of rainfall.
even in valley counties and Sacramento city.
| Q.-What amount of rainfall have you OBJ
served in the Sierra Nevada mountains?
| A.-The largest amount which has come
under my personal observation was, l think.
about ITO inches-105 or Ito inches-in the
year. The average amount of rainfall at that
particular point. which is on the headwsters
of the South Yuba, is about so inches,
think. or So.
@. 10y MIR. Belcher)-What would be the
rule as to precipitation, comparing the valley
with the mountains?
A.-The precipitation, as general thing,
increases until you approach the summit, be-
ing greatest within few miles of the divide
between California and Nevada.
@ tby Mr.. Dibble)-What is the ratio?
A.-Ghe rainfall in the different points Of
the valley varies very greatly-mrch larger
at Sacramento than it is 100 miles to the
south, or at the mouth of the Sacramento
river. It will vary from 3 to Is times. 1t
varies very much in the mountains. Ia one
valley near the summit of the Sierras will be
| 80 per cent. more than in the adjoining val
ley, which is only couple of miles distant.
THE EFFECT OF STOPPING INNING.
OF mining was stopped how much less
material would come down the stream?
A.-Well, think that practically no less
material would come down from the rivers,
certainly not for quite nun Der of years to
come. There might be less of the lighter
material which stains the water. The water
might become clearer perhaps. but the total
amount of material carried even in suspen-
sion, think would remain about the same.
The amount, as l have stated before, of old
material remaining up in the mountains is
very large indeed, and that is bound to come
down. The light material remaining in the
beds OF these mountain streams is very large,
and that is as certain to come down as that
water flows to the sea.
Q by che Court -What do you call that
material?
Al would call ihatmaterial that which has
comefrom the old surface washings of the mines.
It is sand, small gravel and very often large
quantities of clay, but chiefly sand, because
a very large part of what is known as pipe
clay consists of very finely commiDuted sand.
You very often find thick beds of pipe-clsy
from Is TO 20 feet thick-which is nothing
in the world but very tine sand.
@. 10y MIR. Dibble)-Does material from
other sources come down in addition to that
which you have spoken of?
A.-There is what Mr.. Hsll calls the
natural wash from the mountain sides.
Q-What do you call natural wash?
ALL of this material brought down the
streams, which not directly or indirectly
came from the mines, is included by Mr.. Hall
in the term natural wash. l would conhne
my definition of natural wash to the wash
ines of an unoccupied and uncultivated soil
by nature alone, without the soil being dis
turbed; that would be my definition Ct ma
tural wssh-of the natural erosion which is
going on in country not disturbed at all by
the action or work of man. Where the soil
has been disturbed by agriculture / would call
it agricultural wash. The surface of plowed
ground is washed eff much more easily than
soil that has never been disturbed.
/ Q.-What is the effect of the building of
roads?
Avery act of civilized man adds to the
amount of material which is washed from the
surface Of the country-increases that ur-
avoidably. Those roads which you find in
the mountains you very frequently see four
or five feet below tie surface of the ground,
which is the result of the passing of wagons
and the grinding up of the soil into dust,
which has blown or washed away.
Q.-What is the effect Of cutting off tim
Der?
A.-That adds necessarily to the amount of
wash or erosion.
Q-How about snow slides, land-slides or
frost?
A.-Of all the natural elements frost is the
greatest in producing an erosion of the sur