Irrigation glossary

Zone — the sprinklers or emitters on one valve, running together. Valve / solenoid — the electrically operated valve that opens a zone when the controller energizes it. Controller / timer — the device that decides when zones run. Station — a controller output wired to one zone's valve.

Precipitation rate — inches of water per hour a device applies. Sprays are high, rotors are low, which is why they can't share a zone. Head-to-head coverage — spacing heads so each one's spray reaches the next, which is how uniform coverage is achieved. Matched precipitation rate nozzles — nozzles designed so different arc patterns apply water at the same rate.

Backflow preventer — the assembly that stops irrigation water being drawn or pushed back into the potable supply. Backsiphonage — backflow caused by a pressure drop in the main creating suction. Backpressure — backflow caused by higher pressure on your side pushing water back. Cross-connection — any physical link between potable water and a non-potable source.

Evapotranspiration (ET) — water lost from soil and plants combined; weather-based controllers use it to size watering. Cycle and soak — splitting a runtime into shorter intervals so water absorbs instead of running off, which WaterSense recommends on clay soils and slopes. Drip / emitter — low-flow devices delivering water at the root zone. Swing joint — a flexible connection that protects buried pipe when a head is struck.

How to choose

Learn three terms before quotes

Zone, precipitation rate, and backflow preventer. Those three cover pricing, performance and compliance.

Ask for the zone map in these terms

Zone number, area covered, device type, and runtime. That's a usable document.

Recognize the backflow vocabulary

Backsiphonage and backpressure are the two mechanisms your device type is chosen to address.