Fig. 3. Illustration of water flow parameter estimation for linearizing the Warrick (1974) analytical flow model, (a) successive approximations of and K_s by using tangents to the K(h) versus h curve, (see Table 2 for values), (b) estimated k() = dK()/d using the van Genuchten (1980) model and some estimated k() values from flow experiments with different ranges of water content.