Why does tap water have naegleria fowleri in it?

AMOEBA: Tap water that is drinkable should NOT have this pathogen in it!

N Fowleri in tap: water is rare. It would be found if water is contaminated. "Naegleria fowleri can grow in public and private water tanks and pipes, especially where little or no disinfectant (like chlorine or chloramine) is present. It can also grow in the pipes and water heaters of homes and buildings." REF: https://www.cdc.gov/parasites/naegleria/tap-faucet-water.html