Can you swim in Kamikochi?

I am traveling there from October 3-7 and since weather is expected to be nice, I am wondering if you can swim in the rivers there?

I wouldn't think so, the side of Taisho-ike pond is all swampy and further upstream it is all rocks and you can wade through the river.

You probably would have more fun at the bokuden-no-yu cave bath at Nakanoyu onsen which is located just before the entrance of the bus-only tunnel entrance to Kamikochi at the Nakanoyu bus stop.

This is the river that we encountered at Kamikochi: https://www.travelblog.org/Photos/2088180

I went in up to my knees at Taisho pond, near the bus stop. It isnt marshy there, but it is very rocky. It was freezing cold (May this year). I didnt see any signs against swimming, but I dont know that it would be such a good idea, or if it is permitted. There is a nice grotto up a little from there but it is full of mosquitos and midgies.