Roxbury Creek

The Prairie du Sac Dam is the largest hydro-electric facility on the Wisconsin River and divides the river into the “Lower” and “Upper” portions. The “Lower” Wisconsin River is free-flowing from the Prairie du Sac Dam to its confluence with the Mississippi River at Prairie du Chien. ; Because the Wisconsin River below Prairie du Sac Dam remains free of ice throughout winter, this has become an important bald eagle wintering area. The gentle current and unspoiled shoreline makes the Wisconsin River below Sauk City popular with both canoeists and small boat anglers.

Gamefish species prey heavily on gizzard shad as well as emerald shiner, spottail shiner and bluntnose minnow.

There is a significant movement of wallege and sauger up the Wisconsin River to the Prairie du Sac Dam from late fall through spring. Limited numbers come from the Mississippi River, but the majority are residents of the Lower Wisconsin River. A white bass spawning migration occurs during early April and May.