Page 347 - 1915, Springs of CA.

LAEGE COLD SPRINGS. 327

flow eastward, uniting to form a stream that is perhaps 10 feet wide
and 2 feet deep. The water of two other springs which rise 100 yards
apart at the base of a gentle lava slope at the northwest edge of the
meadow is distributed by ditches to irrigate the natural hay land.
A large amount of water also issues at the northeast edge of the
meadow about 500 yards east of these springs, where a pond is
formed by an earthen dam, so that the level of the water is raised to
a height that renders it available for use on the meadow. Below
this dam a stream 100 to 200 feet wide and 2 or 3 feet deep flows
southward along the western base of a lava bank that borders the
meadow. At several places along the margin of the stream and in
its channel there are other springs of considerable flow. The most
remarkable is about one-fifth mile below the dam at the head of the
stream. This spring rises in an oval pool about 50 by 60 feet across
and 16 feet deep in a depression in the lava nearly 100 yards east of
the main stream. The water in this pool is very clear. It rises
quietly but with a strong flow and joins the main stream 250 yards
southward. The combined flow of the springs, or of Fall River,
which they form, is 1,500 second-feet (675,000 gallons a minute).1
As the grade of the stream is low, water is not easily available for
irrigation by gravity canals and has been used to relatively little
extent.
The springs rise at the southern border of an extensive lava field.
They are locally considered to be the outlet of Tule or Rhett Lake
at the northern border cf the State. The water may, however, be
furnished by the precipitation on the lava fields to the north, for
much the greater part of the water that falls on these fields sinks
into the crevices and caverns in the rock, and there is very little
direct surface run-off. A continual flow of 1,500 second-feet would
be furnished by an annual run-off of 1 second foot from 1,700 square
miles. This amount, 1 second-foot, is not excessive for the region
under consideration, where the annual precipitation is 20 to 40 inches,
for it represents both a normal run-off and the amount that usually
sinks into the ground. There is an area of nearly 2,000 square miles
of lava beds extending from northeast to northwest of Dana, and
the topography of this area is favorable to the hypothesis that it
may furnish the water of the springs at the head of Fall River.
The temperature of the water, 53° to 54°, indicates that it is of
essentially surface origin.
LARGE COLD SPUING SOUTHEAST OF PITTVILLE (LASSEN 3).
On Mr. George Guthrie's ranch, 3 miles southeast of Pittville, or
16 miles in a direct line southeast of the big springs at the head of
Fall River, there is a spring whose water is probably essentially of
1 Clapp, W. B., and Hoyt, J. C., Report of progress of stream measurements for the calendar year 1905:
U. S. Geol. Survey Water-Supply Paper 177, p. 133, 1906.