Each municipality in the United States publishes a water quality report. Most reports are lovely brochure like documents and can be downloaded from your local water government office. These reports feature the levels of allowable contaminates according to the EPA. In order to know if you have contaminates in your water, you should have it tested by an independent lab like https://watercheck.com/ or https://mytapscore.com (We are not affiliated with either testing company.)

According to the CDC: "If your local health officials issue a boil water advisory, you should use bottled water or boil tap water. This is because a boil water advisory means your community’s water has, or could have, germs that can make you sick."