South of the O'Sullivan Dam and for patches south and west is the Columbia NWR, which is subject to certain day openings, and noon openings for upland. The Reservoir itself is game area, state park, and some private on the east bank. Mostly game area, which is open all the time.
I was told some years ago by a park ranger friend that Banks Lake state park had foot access to waterfowling areas to its North, but I've never been to check it out myself. I'd like to know about the land ownership (State, Federal, or Private) of the land to the East of Banks.