This paper describes theoretical development and laboratory experiments for the flow process in layered slope sandwiching coarse sand under a steady-state flow condition. We introduce the concept of initial and effective water entry values for the lower layer with nonuniform grain-sizes, and present theoretical arguments for the characteristics of the flow domain in the capillary fringe above the textural interface. The experiments were conducted using a two-dimensional glass chamber to support the arguments. The results show that two types of flow occur : the lateral flow rapidly moves through the capillary fringe and the breakthrough flow penetrates the coarse sand with relatively low flux. According to flow pattern, the flow domain is distinguished as follows: upper no-breakthrough zone(zone 1), breakthrough zone(zone 2), and lower no-breakthrough zone(zone 3). It is further shown that two no-breakthrough zones are governed by different mechanisms, and that the breakthrough zone may include the partial leakage which leakage rate is smaller than rainfall rate