The Castor River Diversion Channel is a 34-mile man-made waterway in southeastern Missouri that intercepts and diverts the Castor River, Whitewater River, and Crooked Creek eastward to the Mississippi River near Cape Girardeau. Created in 1913, this 7th order channel serves as a flood control structure within the larger 1,207 square mile Headwater Diversion Basin. The channel transitions from clear, Ozarkian headwaters in the northwest to slower, more turbid lowland habitat as it approaches the Mississippi River. The diversion channel receives more fishing pressure than other parts of the basin, accounting for three times as many angling trips and seven times more angling hours per acre than the Castor River itself. Water clarity ranges from crystal clear in the upper reaches to muddy in the lower sections, with flows significantly influenced by Mississippi River stages during flood periods.