Koren et al (2000) and others have investigated using soil types as a basis for determining, a priori, initial values for SAC-SMA model parameters.
In particular, Koren has developed physically based procedures to quantify 11 major parameters of the SAC-SMA with soil properties.
The procedure is based on soil characteristic assumptions and Natural Resources Conservation Service (NRCS) soil data.
Using the NRCS curve numbers and soil profiles, UZTWM, UZFWM, LZTWM, LZFSM, and LZFPM can be estimated as functions of soil porosity, field capacity, wilting point, soil depth and the SCS curve number.
Empirical relationships can then be used to determine other parameters such as ZPERC, UZK, LZSK, REXP, and PFREE.

The reader is referred to the paper by Koren for details of this technique. Model parameters and feasible ranges based on this work appear later in this section.