I've overnighted at the tailrace a couple of times. Shorefishing. Fish until I can't stand it any longer, then conk out in the vehicle for a few hours, and then hit it again in the morning. You can park up top. While not strictly legal (but not strictly CAMPING - with no tent, and no cooking and no fire or chairs or anything) I think most of the sheriffs or game wardens turn a cheek at this type of thing. There are vehicles coming and going at all hours, when the fishing is on.
Most times, the morning bite has been worthless. Should have just headed back to Bismarck at 3AM.