Drinking water/filtration

Arizona has horrible water. We always used tap water until we got out here. Some areas of N Mex and Texas aren't good either. I always check google for water quality for the areas we are at unless we will have city water. Found that some states do not require any type of testing on wells. Only requirements are for city water systems. Yuma has very high salt content - so much so the water is slimy. Most of the rest of the state also has high arsenic amounts and N Mex has uranium and other mining compounds at high levels. Michigan is currently testing all public water systems and finding PFA's in the water systems. I'll bet there's a lot more they don't know than what they do.