The issue wasn't lead contamination in water it was because people used leaded gasoline and lead in household paints in the 1970s. DC still has 1200+ sections of lead service lines. Generally, they don't result in lead contamination. A study was released that stated that, obviously, the risk of contamination is higher than a different pipe material.

I think lead contamination, while a contributing factor to neurological damage, is more of a red herring when it comes to behavioral issues of juveniles. Otherwise we would see a correlation with juvenile crime and lead exposure.