I submit that we might also be looking at issues with copper piping. Depending on who you talk to, there could be issues there. Even PVC piping is cited by some as having the potential to give off nasty things into the water.
A lot of it will depend on the chemistry of the actual water being supplied to the communities. It's almost as though we need to take it on a community-by-community basis rather than necessarily looking at a one-size-fits-all remedy.