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I lived in New York City for decades and drank tap water every day.  NYC has some of the best tap water in the world, especially considering that it sits at sea level.
The water comes from upstate aquifers which are heavily regulated.
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People who live in countries with clean tap water should be grateful.

Several cities in the U.S. have used a similar system called indirect potable reuse, or IPR, for decades.

In that system, sewage water is treated at a wastewater treatment plant, which cleans it to a level that meets the standards for irrigation, or for watering land and crops. The water then gets sent to an advanced purification facility, which McCurry says cleans the water even more, typically putting it through a three-step process that ensures it meets or even exceeds state and federal standards for drinking water quality.

By this point, the water is clean. Still, it then goes into an “environmental buffer” like an underground aquifer, where it can spend months or even years to undergo further filtration. Finally, it goes to a drinking water system for distribution