This 20-year test program evaluates the short- and long-term corrosion interaction between a soft aggressive water supply and thin-wall stainless steel and copper pipe, painted ductile iron, and various coupling techniques (mechanical joints and welded joints) in both primary building supply water service and fire standpipe service (stagnant conditions). Pipe and coupling samples will be removed periodically over the 20- year period; at the end of the service period, the test stand will be disassembled and evaluated. Evaluation techniques will include surface analyses, scanning electron studies, and energy dispersive spectroscopy in addition to visual examination. Water analyses and standard weight-loss corrosion coupons will be used to evaluate the changes.