Spray heads typically discharge water compared to rotors by:

• A. About the same
• B. About half as much
• C. About three times as much
• D. Ten times as much

Answer: (C)

When comparing irrigation heads, the rate at which water is discharged is the key difference. Spray heads are designed to deliver water in a fixed, broad spray with relatively large openings, so they apply water more quickly at typical operating pressures. Rotors, by contrast, rotate to distribute water over the area more slowly, using smaller flow rates and longer cycle times to ensure the water infiltrates rather than runs off.

Because of that slower, more distributed application, rotors have a lower precipitation rate than spray heads. In practical terms, spray heads typically deliver about three times as much water as rotors under common design pressures (roughly 30–50 psi). That’s why the best answer reflects that spray heads discharge water about three times as much as rotors.