Galvanized service corrosion (pre-1960 homes)
Galvanized iron service lines installed before 1960 in Brockton have reached structural end of life. The interior zinc coating wears out, the iron oxidizes from the inside, and eventually a pinhole or full split develops. The water-bill signature is gradual — slowly rising over months as the corrosion progresses — until a full break suddenly empties the line into the lawn.