Tulsa was in the Top 25 American cities for tap water. The drinking water comes from three lakes in northeastern Oklahoma. The city monitors pH, turbidly, chlorine, and other water quality tests every 4 hours. The distribution is tested with 200 samples per month. The 2016 quality report says Tulsa water is safe to drink and free of bacteria and harmful substances. [See: 17 Household Items You Should Get Rid of Immediately]