Six models, employing different ways of discretization of the nonlinear infiltration equation were compared in terms of execution time, accuracy, and programming considerations. All models yielded excellent agreement with water content profiles measured at various times in a sand column. The two explicit models, the θ‐based CSMP model and the h‐based explicit model, used between 5 and 10 times more computer time than the implicit models. Results obtained with the two models which used the Kirchhoff integral transformation were no better than those obtained with the two h‐based implicit models. The implicit schemes with implicit, or explicit evaluation of the hydraulic conductivity and water capacity functions appear to have the widest range of applicability for predicting water movement in soil with both saturated and nonsaturated regions. Excellent agreement was obtained between water content distributions, infiltration rates, and cumulative infiltration volumes calculated with the implicit finite difference model and Philip's quasi‐analytical solution.

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The difference between the cumulative infiltration occurring during three-dimensional axisymmetric and one-dimensional vertical flow is a linear function of time. The slope of this line is a function of the source radius, initial and final volumetric soil water contents and the soil sorptivity. This allows the determination of the sorptivity and saturated conductivity of the soil from data of axisymmetric flow in a single ring of small diameter under negligible head of water. The method is based on the optimization of the sorptivity and saturated conductivity on the one-dimensional vertical cumulative infiltration inferred from axisymmetric flow data. To examine the reliability of the method to determine these parameters, numerical threeand one-dimensional data are generated on soils with known hydrologic properties from the literature. The linearity versus time of the difference of the two types of flow is verified. Several physically based expressions for the vertical cumulative infiltration as a function of time are considered. The optimized values of the sorptivity and saturated conductivity are compared to the their real known values. Despite the large errors on the optimized parameters, namely the saturated conductivity, the error on the vertical predicted cumulative infiltration is limited to 10%. This makes possible the application of this method on a large scale for hydrological modelling purposes.