No rapids on the Arkansas in Kansas that I know of (hell lots of sections with not enough water to tube or raft).

One side note, within the borders of Kansas, the Arkansas river is not the Are-Kin-Saw, its the Are-Cans-Es (and any town or street named Arkansas in the state is also pronounced the same). In Kansas if you say Are-Kin-Saw, you better be referring to something outside the borders of the state of Kansas.