146 
FLUCTUATIONS AT COPPERAS CREEK. 
Per cent. 
rainfall..... 
Number of 
rises exceed- 
ing 3 feet in 
Number of 
culminations 
of floods ex- 
ceeding Io 
feet above 
low water... 
Occurrences 
of minimum 
stages forthe 
eee ee eee 
Occurrences 
of maximum 
stage for the 
Average num- 
ber of days 
when water 
was more 
than 8 feet 
above low 
water 
6.7 
.| Feb.|Mar. 
7.0, 
Apr. 
8.2 
May|June| July|/Aug. 
10.5] 12.2} 9.9} 8.6 
Sep, Oct.|Nov.|Dec.| Total 
Io 
Natl 
ie) I 
II.1 
15.8] 24.8 23.9 20.1 
16.8] 7.9] 1.7 
Average num- 
ber of days 
when water 
was less than 
4 feet above 
low water .. 
10.0 
3.8 
ie) 
3.6 4.8] 8.9] 20.8 
1.0] 4.0 5.1 
132.2 
23.2, 25.0, 19.0] 15.0 
134.1 
*Minimum levels reached in two different months in 1887 and in 1892, and in three 
in 1897. 
more than 8 feet above low water—whose duration has aver- 
aged 132 days, ranging from 11 days in 1895 to 230 in 1883. The 
average seasonal position of this period is from February to 
June, inclusive, though portions of it have occurred in every 
month of the year but September. 
In some cases it begins with 
the autumnal rains in October or November and continues 
throughout the winter, as in 1881 and 1889, though in some in- 
stances this early autumnal rise is followed by a sharp and con- 
