Three dimension numerical analyses led from the research which sees abnormal form and the size back of the water purification material conferred the flowing water conduct inside the test channel against the test condition. Comparison it analyzed the flux distribution, a water depth of the channel which establishes the water purification material the cross section, an interval of the water purification material, a conference with with general channel, it change executed. Also it abridges with a channel and executes as analyzed the hydraulics quality of the water purification material which is not standardized a model test. The flow changed the cross section of the water purification material from schedule one condition and it measures a water depth and a flux, fixes the cross section from the condition which a water depth, a flux and interval of the water purification material changes measures as to examine closely the relationship between the water depth which follows in interval of the cross section, the water purification material, flux, executed the comparison an analysis, a revision of three dimension numerical analyses, it decided a water purification material form, an arrangement and the result confirmed comparison agrees well.