Right on the Umpqua, at the very edge of the little hamlet of Oakland OR. It's small so it could fill up fast, but darn it's a sweet little spot tucked away in an unlikely part of Oregon. I came here on an August Friday and it was FULL. It's a perfect place to go tubing on the river, so I'm (sad but) not surprised.
Very nice campground, the local Boy Scouts added amenities. It is the most deluxe BLM campground I've ever seen. Showers even! There is apparently a waterfall a mile or so up the hill across the road.