This start of a story makes me think of the Columbia Gorge Falls I visited, early nineties. On that scenic route on the Oregon side of the river, there are a number of waterfalls, the best known, and also the most accessible, is Multnomah. That's where all the tourists hang out. Trails, viewing bridge, gift shop, restaurant etc. I wanted to get away from the crowds. I cannot remember which one, but at one place I decided to hike to the fall, which was visible, but deeper set in and seemingly inaccessible. There was no trail, I walked in the water that was not very deep to begin with. As it got deeper, I took my clothes off and put them together with my other belongings (including knapsack) into a large garbage plastic bag I always carried (one of the things you always have with you in this type of terrain). Eventually, the water was up to my chest. And like in this story, there were walls on each side with the water rushing through, and some deeper pools I swam through to get my feet onto the bottom again, but after a while I gave up and returned, once the water was up to my chin at the best of times, with more and more deeper sections to swim. Hard to keep your balance if you hold your belongings overhead. It was cold, but I did not notice with the adrenaline going. I only noticed when I got back to dry ground. It took a while to stop chattering enough that I was able to put my clothes on again. My fingers were so numb, I struggled to untie the knot of the plastic bag.
This is the area: https://2traveldads.com/2016/02/28/waterfalls-of-the-columbia-gorge/ (over 20 years later, but by the looks, not much has changed).