I wonder if they wash water pipes with anti-bacterial soap. How sterile is our tap water? Water pipes lay outside on the side of the road exposed to all the elements and wildlife before they are buried. Then the flush them with, as far as I know, just regular city water. The way the pipes and water system are kept “clean” is just by keeping the system flowing. Stagnant water provides a place for organisms to grow. The system is designed to avoid dead ends. If there is a dead end they put a valve or a fire hydrant at the end and it is “supposed” to be flushed out periodically.
From the 2003 Greensboro City water quality report:
“1,875 water samples were collected at various points in the distribution system to test for bacteria such as Total Coliform and E. Coli. No harmful bacteria were present in any sample.” Notice it said, “no harmful bacteria.” That does not eliminate the possibility that there were harmless bacteria in the water. There may be bacteria in your water. You scrub with anti-bacterial soap and then you rinse it off with water that may contain bacteria!
I think the fight against bacteria is wrong-headed. Every inch of your body is covered with bacteria. If you took a sterile swab and wiped it on any part of your body and then rubbed it on a bacteria culture and let the culture grow for a couple of days, you would see a nice fuzzy blob of bacteria. There is bacteria in your mouth, eyes, large intestine, etc. Small amounts of bacteria are normal. What we need to avoid are large concentrations of bacteria and known sources of harmful bacteria. Usually your nose will alert you to these hazards: spoiled food, feces, rot.