Most cities, including mine, use chloramine, which does not evaporate. I bought a water conditioner liquid that is used for fish aquariums which from my understanding, splits chloramine, into ammonium and chlorine, and from there it will evaporate. Correct me if I am wrong, anyone.
Also water reports are public property available from the utilities companies website, at least mine is. It shows all the tds /ppms, cholramine, ph values etc, tested on a monthly basis