How Kanab Canyon, a side canyon of the Grand Canyon, may have developed within a young-earth Flood model is discussed. The draining of a lake ponded in southwestern Utah and possibly northwestern Arizona was the major cause for the formation of lower Kanab Canyon. Upper Kanab Canyon has developed since the 1800's because of flooding from thunder-shower activity. The following phases of erosion are postulated; a. during the retreat of Floodwater, b. draining of a post-Flood lake, c. precipitation during a warm post-Flood ice age, d. recent erosion from thundershower activity. Periods b and c may have overlapped chronologically. Processes such as cliff sapping are necessary to explain some of the topography of the high plateaus region of southwestern Utah.