I grew up a swimmer, started swimming competitively when I was about 6 years old. I swam competitively until I graduated College. I started teaching swimming lessons when I was 14, lifeguarding when I was 15, coaching when I was 16. I taught lessons, coached swim team, and guarded until I graduated college. I also ran 3 different pools as Manager (and head guard) during college, two being Olympic (50meter) facilities, one being 25 yards - all 8 lane pools. I've now owned my own backyard pool at one home since 2001 or 2002, and again in our new home.

In all that time, all those thousands upon thousands of hours in, and beside a swimming pool. I've never, not once, heard of a person getting sick from swallowing pool water. Also, as per my statement previously, municipal (tap) water IS chlorinated. "According to the U.S. Environmental Protection Agency (EPA), chlorine levels of four parts per million or below in drinking water—whether from a private well or municipal reservoir—are acceptable from a human health standpoint." "Today some 98 percent of water treatment facilities in the U.S. use some form of chlorine to clean drinking water supplies."

Source: http://www.pottsmerc.com/article/MP/20130318/LIFE05/130319340

The "third world" country I live in the USA, which generally speaking (flint being an obvious outlier) has a fantastic water supply.