TITLE:
Rainfall Infiltration Return Frequency Estimates
AUTHORS:
T. V. Hromadka II, M. Phillips, P. Rao, B. Espinosa, T. Hromadka III
KEYWORDS:
Infiltration; Depth-Durations; Return Frequency; Infiltration Estimates; Probability Distributions
JOURNAL NAME:
Atmospheric and Climate Sciences,
Vol.3 No.4,
October
21,
2013
ABSTRACT: Depth-duration analysis, such as accomplished for rainfall, can be
useful in the analysis of infiltration of rainfall. The assessment of
infiltration depth-duration in terms of return frequency is of interest. In
this paper, depth-duration values of daily rainfall infiltration are estimated using the National Resources Conservation Service (NRCS) Curve Number
(CN) approach for estimating daily runoff. The CN methods may be generally
applicable to soils that are free draining. From the estimated history of daily
infiltration, a depth-duration analysis is accomplished for all duration sizes
from 1 day to 365 days. These annual outcomes are then analyzed as to a
possible underlying probability distribution. For the rain gages considered,
the depth-duration infiltration estimates (using the CN approach) appear to be
normally distributed. From the fitted distribution, estimates of rare events of
rainfall infiltration may be made, and possible linkage to earth movement
events accomplished with respect to return frequency of infiltration, which in
turn can aid in the design and risk assessment of fixed works involving soil
water accumulation.