In another lifetime I worked for Coke....well really CCE, Coca Cola Enterprises, the bottler. "Big Coke" in Atlanta just makes the syrup. Big coke owns like 51% of CCE, but it is a different company.
When I worked there over 20 years ago....can't believe it is this long. The "water thing" was just hitting. Dasani was made to counter Pepsi's Aquifina. Dasani is basically what ever water is available in your area, run through a bunch of filters, to get rid of all the other crap the .gov puts in water, including poison, fluoride. (For a fun way to spend 2 min read the back of your tooth paste tube, it tells you to not let kids brush their teeth for over 2 min, and to call poison control if you "eat" it)
They then add their own stuff to it, and that is all it is.
Make no mistake it is very good and pure water, run through filters you could not imagine, just like the water used in the pop.
Now the pop you get at a quick shop, or when you go out to eat is different, and that is just city water, it might have a filter on it, but in my old area usually not unless you are in a very small town on a well. Most of what is in quickie marts and such is a product called bag in a box.