Abstract
A study is carried out of the possibility of synthesizing the storage function model which is regarded as one of the representative models for flood runoff analysis in Japan, in order to expand the applicability of the model being basically the lumped style to a watershed with several land use conditions.
The storage function model has three parameters, K, P and Tl, as seen in the following fundamental equation
Sl=KQP=∫0t-Tlγedt-∫0tQdt, Sl
in which, S1 is the hypothetical storage depth of rain water over the watershed considering the time lag T1 between rainfall excess re and flood runoff discharge Q.
P=0.6, K=βA0.14, Ti= γA0.14γe-0.14, in which A is the watershed area (km2), re the rainfall excess (mm/h) and both, β and γ are the coefficients depending on the land conditions.
Next, the reasonable method for applying the storage function model as a distributed model using the above-mentioned formulae is discussed and its usefulness is verified.
