Which pipe material is generally favored for water quality, alongside PVC and Concrete Pressure?

• A. Cast Iron
• B. Lined Ductile Iron
• C. Steel
• D. Copper

Answer: (B)

Maintaining water quality in a distribution system hinges on choosing pipe interiors that resist corrosion and don’t leach metals into the water. Lined ductile iron uses a protective lining (cement-mortar or epoxy) inside the ductile iron pipe, which isolates the water from the metal, greatly reducing corrosion products and taste/odor changes while still offering the strength and durability of iron. This combination makes it a preferred option alongside PVC and concrete pressure pipes for preserving water quality. Cast iron and steel are more prone to corrosion and can affect water quality, and copper, while resistant, is usually more expensive for large mains and has regulatory considerations, so it isn’t as broadly favored for distribution pipes.