Is the water from a private well safer than municipal water?

Don’t assume that. The quality is determined by what’s in the aquifer from which the water came. Potential aquifer pollutants include the following: septic tank seepage, gasoline from leaking underground tanks, fertilizers, pesticides, and industrial waste. Be sure that you have your well water tested regularly to be sure it’s safe.
 
Also, be sure that tests of your well include a determination of the fluoride content. Fluoride is present naturally in some wells but not all. Children under the age of 14 need fluoride to strengthen their developing teeth. If your water supply doesn’t have a sufficient amount,
your doctor or dentist may want to prescribe fluoride drops or chewable tablets. Fluoridated toothpaste and rinses are generally enough to protect teens and adults against tooth decay.
 
Source(s):
Consumer Reports The Best of Health by Marvin M. Lipman, M.D. and the editors of Consumer Reports on Health, 2009