Bathing or drowning?

I need your erudition, folks. Recently I found this unusual painting on the internet. I've never seen a naiad depicted this way before. Maybe she is not a naiad but some other mythological female? Is the lady drowning? Or maybe she is bathing? I don't know the artist and I can't figure out if the image might be an illustration for some obscure legend or medieval novel. Do any of your know what this is supposed to be?