Selecting the right pipe material for your water main is critical for water quality, longevity, and compliance with NYC building codes. Copper is the standard choice for residential water service lines in NYC, offering excellent corrosion resistance and a lifespan of 50-70 years. Ductile iron is used for larger water mains and offers superior strength and durability. HDPE is gaining popularity for its flexibility and resistance to corrosion. Lead and galvanized steel pipes should be replaced immediately due to health and performance concerns. NYC DEP has specific requirements for water main materials that must be followed.