I've alluded to this on in some of the other threads, but I will here, too. The entire Great Gulf is drained by one river, the Peabody. I was camping once by the Wamsutta Trail intersection, and after two days of rains and I decided to bail on the last day and headed out. The entire time, I was thinking about the crossing by 'The Bluff'. I had rock-hopped across it two days earlier, but the rocks were not too high over the water line and I thought it might be a problem. It was.
I got to the river's edge and the water was easily 3' higher than it earlier. I stood looking at it for about five minutes, then decided to go for it. I tied my dog to my pack, loosened it, grabbed my poles, and started to wade across. The water immediately swept my dog down stream, over a 4' ledge. "Well, I no longer have a dog" was my immediate thought. Fortunately, she didn't go completely downstream as she was held by the rope I had fastened her to. She was struggling, and I was trying to stay upright. Somehow, she managed to climb back UP the ledge, against the current, and with me encouraging her we made it across. She was freaked. I was freaked.
I would not suggest that trip unless the water levels drops.