If you have “city water”, your supplier is required to test your water on a regular basis (check your water company website or call for specific information). If you have a private well, it is up to you to have the water tested! It is a good idea to have your water tested on a regular basis to detect any changes in quality. A standard potability test can be performed at many state-certified lab. Additional information can be found in this CT Dept. of Public Health Publication on Private Well Water.