Cheyenne River Arm of Lake Oahe. Foster Bay is at the far west end, it's handy to put the boat in there and then run a couple miles east for good fishing. But, low water levels make it not usable. Regardless, there is not much for fishing right around the ramp, you always travel east. Minneconju is another boat ramp about midway down the Cheyenne Arm. I don't know if there is even ice to that point yet.