To restore a ground water flow cut off by a soil cement column strip earth retaining wall.

A soil cement column earth retaining wall A using an H-section 3 as a core by holding a construction ground B between soil cement column strip earth retaining walls is embedded in an impermeable layer E located under a permeable layer D over it to form. In that case, a steel pipe 4 incapable of reaching the permeable layer D is inserted in part of the earth retaining wall A. Then, the steel pipe is inserted from the ground to excavate a part of soil cement under the steel pipe, and a permeable hole 5 connected with the permeable layer D is bored.