Does the water have any kind of smell to it, or does it leave a smell on your skin after wading through it? Probably ultrapure from filtering through the rocks, I'd imagine, although there are microorganisms that live in some caves so maybe not?
The limestone above is not high enough to really filter out whatever the farmer on top throws on their field, so it's contaminated with pestizides and not recommended for drinking. It smells like fresh water.