Homeowners who have a private well are responsible for maintaining and testing their water supply. Testing should be done once a year or at the time of a home inspection or well construction. Renters who are concerned about the quality of their well water should request that their landlord have it tested. If the landlord does not comply, the renter can contact their town health department or regional health district to inquire about well water testing. As with tap water, well water samples are sent to labs for testing if they are thought to be a health hazard.