Seriously, The water is flowing way to fast. then soon the waterfalls. Now people do dip their feet in the water, but even that is not advisable.
I would not risk swimming in the river. Looked like swift waters when we were there, I did see kayakers below the falls some distance away.
When we visited the river had a very swift current and I wouldn't advise swimming, especially with children. Maybe down river from the falls there is a calm area. I have no idea.
There is no swimming in the river near the parking lot and gift shop. When you first arrive you can't tell, but it is just a few hundred yards from the top of the falls. The water is typically not running very fast so it appears safe, but it isn't.
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