There are thermal rivers too... didn't see any of those or any of the small, semi secret bathing pools, but there are a bunch that locals go to. It's a big part of the culture there. Almost no one has their own swimming pool but pretty much every town has a big, geothermally heated public pool with slides etc. I thought that was funny.
Regarding swimming in the ocean, numerous signs for "sneaker waves" that drag people out now and then. Different than rip tides I guess.