If you are interested in what is in your water, or the laws that govern what can be in your water, there are several places you can turn. You may want to use multiple sources, so that you can compare the results, if you do not trust the local authority on the matter. All municipalities are required to have their water tested on a yearly basis, and the Freedom of Information Act means that you have access to the information that they have as a result of the testing done by drinking water testing labs. This information is also published, so you may be able to access it through your local papers.
Homeowners who get their water from a well are not required to send samples to drinking water testing labs, unless they are gathering information in order to get a permit to build a home, or they are planning to open a business, such as a daycare in their home.
Your first stop should be the town hall, where this information should be recorded. You may have to pay a small fee for the records, but they are available to the public. You can then order your own water testing to be done and compare your findings with those of the municipality findings. Some resources you could refer to for more information on clean water would include the Environmental Protection Agency, as well as the Clean Water Act and the Department of Health and Human Services. Any of these resources can give you in-depth information about the details of water requirements in your area.