Which of the following is a hydrant supply system?

• A. Water distribution ring main
• B. Pumped loop system
• C. Circulating loop system
• D. Dead end system

Answer: (D)

Hydrants receive water from a defined distribution arrangement, and a dead-end system is one where the feed main extends to a terminus without looping back to form a ring. Hydrants are tapped along that single line, delivering water directly from the supply main. The defining feature is that there’s no alternate path for flow; if the main is restricted or becomes failed, there isn’t a built-in loop to keep water moving. This setup still serves the purpose of supplying hydrants, which is why it’s categorized as a hydrant supply system. In contrast, ring mains create a closed loop for multiple pathways and more stable pressure, while pumped or circulating loop configurations rely on pumps and continuous circulation to maintain pressure. Those differ from the straightforward dead-end feed.