Quoted:
Even though we all did this as kids, drinking from a garden hose is really not safe, especially if you have animals around the yard (fecal matter contamination).
Drinking from the kitchen sink or bathroom tap = fine, although not always tasty.
Leaving a garden hose connected and laying on the ground is actually a hazard... it creates the potential for cross contamination if there is ever a negative-pressure in the water system... essentially, if there are animal feces, or other chemicals in the lawn, and there is a watermain break severe enough to eliminate all positive pressure in the system, that fecal matter or those chemicals can actually be sucked into the water system through that hose... when pressure is restored, it gets pumped back through the system to all of the consumers. Mmm, tasty!
Also, "City water" is typically better for you than well because it is strictly monitored (we test ours monthly searching for Coliform, which is an "indicator" bacteria that lets us know if there may be something more dangerous in the water) and because it is flouridated, which helps strengthen your teeth. It has been proven that people who drink treated water have fewer cavities than those who drink well water. Our entire water table in my area has a significantly elevated level of arsenic...
<–– Water / Sewer Laborer, and Michigan DEQ S3 Certified Operator.