Discussion of the U-Shape Flow Paths Model

The local, intermediate, and regional flow regions, depicted in Fig. 2.19 as an outcome of the U-shape model, are hydraulically nonlogical. There is 

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If the principal premise of the model, namely, the existence of the three impermeable boundaries, is wrong, then the whole model collapses and the discussion could be terminated at this point. But the notion of deep U-shape flow paths prevails and warrants discussion of the feasibility of its conclusions. 

Presentations of the U-shape model in the literature do not specify the location of rain or snowmelt water and do not discuss the resulting recharge distribution. Commonly, rain falls over the entire area of an unconfined system, as depicted in the cross-section shown in Fig. 2.20. Runoff, too, is all over, but with an uneven distribution, as it runs fast from the topographic highs and accumulates and flows relatively slowly at the topographic lows. Thus recharge takes place all over the surface, but is intensified in the 

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