The Safe Drinking Water Act mandates that all public water companies test the drinking water they provide. The U.S. Environmental Protection Agency (EPA), your state health department, and your water company work together to test the water and ensure it is safe to drink.
Water suppliers must test drinking water a specified number of times each year for microbes and certain chemicals. The frequency of the testing varies depending on the population served by a water supplier. Federal regulations also mandate these tests be conducted in federally certified laboratories using federally approved methods. Many of the larger water utilities have their own certified laboratory and technicians.
No federal regulations mandate the testing of private well water. It is the homeowner's responsibility to test the drinking water from his or her own well. Contact your state or local health department or your local Extension office for information on what to test for, how often to test, and where to have the test done.
For more information see "Private Drinking Water Wells" on the Environmental Proection Agency's website: http://www.epa.gov/safewater/privatewells/index2.html
