Emitter flow rate is defined as the volume of water emitted per hour. Emitter spacing is the distance between emitters along a line. What is emitter flow rate best described as?

• A. The distance between emitters
• B. The irrigation cycle length
• C. The volume of water emitted per hour
• D. The water pressure at the emitter

Answer: (C)

Emitter flow rate is the amount of water an individual emitter releases over a set period, typically per hour. This makes it a volume-per-time measure for each emitter, expressed in units like gallons per hour or liters per hour. It’s independent of how far apart emitters are along a line (emitter spacing) and independent of how long the irrigation event lasts (irrigation cycle length). Pressure at the emitter can influence the actual flow, but the fundamental concept described by flow rate is the volume emitted per hour. This rating helps you size and design the system to meet the desired application depth.