Washington Suburban Sanitary Commission (WSSC) changed its chemicals at some point in the late 1990s, and a lot of customers found pinhole leaks starting in their copper pipes. Considering the relative density of lawyers in suburban Maryland, I suppose there must have been a lot of litigation, though I don't remember hearing.

On the other hand, I lived in a rowhouse built during a brief window in which it was OK with the code to run PVC from the main into the house. Whatever PVC is good for, it doesn't handle shearing force well. Essentially all of the townhouses needed repairs (a copper "pigtail" through the wall).