Public drinking water in Delaware is carefully regulated to help ensure the health and safety of the communities it serves. Public water systems that supply at least 25 people are required to meet federal and state water quality standards. These systems conduct regular testing and apply treatment processes to remove harmful germs and chemicals. While most public tap water meets safety standards, contamination can sometimes occur. When this happens, utilities are required to notify customers and provide guidance on how to stay safe. As a resident, you can take simple steps to stay informed about your water quality—review your utility's annual water quality report, sign up for alerts from your local government or utility, and follow recommendations during drinking water advisories.

Data presented below combine public water supplies for the selected geographic region, and only a selection are listed. Major water providers for Delaware include Artesian Water Company, City Of Wilmington, Suez Water Delaware and, Tidewater Utilities.