Zone Capacity (GPM) Tool

Water pressure is the key to healthy coverage. Before you install a single head, use this tool to calculate your available flow and ensure your zones are engineered to pop up and perform every time.

Zone Capacity Tool

Step 1: Find Your GPM
Run a hose into a 5-gallon bucket. Time how long it takes to fill.
Formula: 300 / Seconds to fill = Your GPM.

Step 2: Total the Heads
List the GPM requirements for each head you plan to install in this zone.

Available Flow (GPM)

Number of Heads

Average GPM per Head

Irrigation Knowledge Base

SAFETY FIRST The 75% Rule

Never design a zone to use 100% of your available water. Pressure fluctuates throughout the day. Professionals design zones to use only 75% of total capacity to ensure heads pop up fully every time.

PERFORMANCE Matched Precipitation

Avoid mixing "Rotors" and "Spray Heads" on the same zone. They put out water at different rates. Mixing them leads to brown spots in one area and puddles in another.

PRO TRICK Friction Loss

Water loses "push" (PSI) as it travels through pipes. If your zone is more than 100 feet from the valve, use 1-inch pipe instead of 3/4-inch to keep your pressure high enough for the last head.

PRO TRICK MP Rotators for Efficiency

If your "Bucket Test" shows low GPM, use Multi-Stream Rotators. They use significantly less water than traditional sprays, allowing you to put more heads on a single valve.