In many places in the US this would be straightforwardly illegal, and caught very quickly. But some of the states that are not known for having swimming pools don't bother regulating swimming pools very much and don't have very many people doing enforcement. Even so, if they were to be sued by someone who swam in the pool and subsequently had a problem they would be in big trouble.
Of course there is another possibility. The news reporter could simply have it wrong. They may simply be lowering their chlorine level, rather than eliminating chlorine.