When I went last year, there were people swimming and splashing there. The river was flowing. This year, we went and the river was shallower and had less of a current, so idk if you could actually swim, but you could get dipped and refreshed if you wanted to. I did notice that since the river wasn't as full, the deeper part had still water instead of running water, which made the perfect environment for more mossy stinky water.
You can but try not to get caught by the park rangers
I'm not sure if you could swim in the river but I know you could go in the river the last time I went which was 6 months ago.
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