Black water is water containing human waste.

• A. Yes
• B. No
• C. Only in septic systems
• D. Only at water treatment plants

Answer: (A)

Black water refers to wastewater that contains human waste, typically from toilets. So the statement is true because it specifically includes feces and urine that are flushed away. It isn’t limited to septic systems or to treatment plants—the waste from toilets goes into either a septic system or a sewer to be treated, but it originates in the building regardless of where it ends up. For contrast, greywater comes from sinks, showers, and laundry and does not contain toilet waste. This distinction matters in design and sanitation planning, guiding how plumbing and water management are handled.