Storm Analysis 
Magnitude and frequency of floods are considered to be valuable aids 
in evaluating the effect of changes in land use on stream regimen. 
Serious watershed disturbance, or removal of forest, may have definite 
effects on the magnitude of flood flows (13). A marked increase in 
magnitude of discharge, or frequency of floods, following logging would 
be a strong indication that the changes are attributable to forest cut- 
ting; providing there has been no significant change in climatic 
factors. 
The first step in the analysis was the cataloging of £loods2/ for the 
entire period of record. Seasonal distribution of floods occurring 
on all streams is shown in fig. 10. Table 5 presents a summary of 
average, maximum, and minimum number of floods by months. The highest 
frequency of floods occurred in October. The greatest number of floods 
occurred in the 4.00- to 4.99-foot class on all streams. Very few 
flood peaks exceeded 7 feet. 
Table 5.--Seasonal distribution of flood peaks greater than 4.0 feet, 
1949-1953 
:_Maybeso Creek _ :_ Harris River: Indian Creek : Old Tom Creek 
Month:5-yr. Max. Min.:5-yr. Max. Min.:5-yr. Max. Min.:5-yr. Max. Min. 
:Ave. l-yr. l-yr.:Ave. l-yr. l-yr.;:Ave. l-yr. l-yr.:Ave. l-yr. l- 
Jan 1 i! 0 i 2 0 0 iL 0 1 4 0 
Feb. 0 i! 0 0 0 0 0 0 0 iL 3 0 
Mar. i! 2 0 0 i 0 i 3 0 0 1 0 
April Sl 1 0 0 22 0 0 0 0 1 3 0 
May 0 1 0 1 2 0 0 0 0 0 2 0 
June 0 1 0 0 2 0 0 0 0 0 0 0 
July 0 1 0 0 0 0 0 0 0 (0) 0 0 
Aug. 1 3) 0 uf 2 0 0 0 0 0 0 0 
Sept. 2 4 0 4 6 0 1 3 0 it 2 0 
Oct. 5 6 4 7/ 9 6 1 3 0 3 8 0 
Nov. 72 3 2 3 6 2 0 1 0 72 5 0 
Dec. 2 4 1 2 5 if 0 1 0 1 4 0 
9/ A flood is a relatively high flow as measured by either gage height 
or discharge quantity. In this section, a flood has been defined as a 
high-water stage of four feet or higher. 
Sui Oue 
