Abstract: When granite weathering crust is weathered from unweathered rock to residual soil,the pore space which affects the permeability changes from fissure to pore.As the layer is from intense weathered rock to residual soil,the permeability is from strong to weak.As for residual soil confined water,there isnt an aquifuge in it.The confined water head in intense weathered rock is very high.The water flows vertically.The loss of confined water head is increasing as the permeability is decreasing.We can estimate the loss of the confined water head according to Darcys Law.