The U.S. is huge but it&#x27;s also filled with a lot of people and a lot of local governments, state governments, and of course a federal government.<p>If you want one independent source of proof that U.S. water is safe, consider that almost every U.S. child has blood work done on an annual basis. If elevated levels of lead are a problem, they would be detected at that time, as they were in Flint.