Which color is used to indicate reclaimed water piping?

• A. Blue
• B. Purple
• C. Green
• D. Red

Answer: (B)

Color coding helps prevent mixing different water supplies by making each system instantly recognizable. Reclaimed water piping is colored purple, a standard that signals non-potable water intended for uses like irrigation or toilet flushing. This clear identification helps workers and the public avoid cross-connections with drinking water and prevents accidental contamination. In many codes blue denotes potable water, red is often used for fire protection or hot water, and green is commonly associated with irrigation or other non-potable lines depending on local standards. Purple is the designated color for reclaimed water piping.