What is the role of the discharge line when drafting from a hydrant?

• A. To feed water into the pumper from the hydrant.
• B. To drain water from the pumper after operations.
• C. To vent air from the system.
• D. To measure water temperature.

Answer: (A)

When drafting from a hydrant, the line that carries water into the pumper is the supply path from the hydrant to the pump. Its purpose is to feed water into the pumper so the pump can develop pressure and push water out to the attack lines. The other functions—draining water after operations, venting air, or measuring water temperature—aren’t what this line handles during drafting; draining happens after use, venting is done through priming and air-relief devices, and temperature sensing isn’t the role of the discharge/supply line.