Which term is associated with carrying wastewater to treatment?

• A. Outfall Line
• B. Gravity Main
• C. Vent Pipe
• D. Profile Plan

Answer: (B)

The term associated with carrying wastewater to treatment is gravity main. A gravity main is a sewer line designed with a downhill slope so wastewater flows by gravity toward the treatment plant without needing pumps. This relies on gravity and proper grade to move the flow efficiently. Other terms refer to different functions: an outfall line usually means the discharge from a treatment plant into a water body, not the line that brings wastewater to treatment; a vent pipe is for venting sewer gases; and a profile plan is a drawing showing the vertical alignment and depths of a sewer, not the method of moving wastewater.