Water

^^it's balance, SH.
Some salts and minerals are good for you, some springs are reknown for them. Locally, I can schlep to Manitou Springs for seven different mineral balances from seven different springs. Some are high iron, some other minerals, including sulphur.
In the teens and 20s, soda water was bottled in Manitou, and soem companies created colas from them (remember, at the time, a cola was a tonic and served in less than 7 oz bottles, actually a good, occasional dose for caffeine.)
I grew up in a very warm area, and it was not unheard of to add salt to a Coca Cola or RC to combat the heat (and some say headache).
That's the reason people put peanuts in Dr. Pepper, I'm told. (since I cannot stand DP, I've not tried this)

This fall I went to Moab and got very dehydrated. The fix? salted, dilute lemonade.
While it wasn't tasty, it did the trick. (I also had straight water, this was at dinner)

Now where I live the creeks LOOK good, but giardia (sp? where's that dictionary?) and also heavy metals pollution is rampant. Clear Creek tested high with MTBE (a fuel additive) last year.

I don't know if you have had giardia poisoning, but it is NO fun.
Chlorine dissapates quickly.
When we dye, we fill two 5 gal buckets, one will be a fix soak, one will provide water to mix (and that one lasts a long while). We leave then out for 24 hours (soak) or longer (mix).
Where I live, fluoridation is out of favor, docs prescrbe drops for babies and the parents use or disregard the script.

So your statements are very blanket, and I'd love to see some back up on your claims from reputable sources.