Why You Need an Irrigation Backflow Preventer: Health & Code Compliance

Irrigation runoff carries animal waste, fertilizers, petroleum, trash—virtually anything on the ground. Without a precision backflow preventer, pressure drops pull this contamination into drinking water.

How Backflow Happens

Negative pressure in plumbing (from fire hydrant use, main breaks, construction) reverses flow. Irrigation water—now a toxic cocktail—siphons past valves into potable supply. Valves can't prevent this; they're not backflow-rated.

Regulatory Reality

Most areas mandate preventers. Even rural properties need them. This is foundational to safe municipal water.

Device Options (Cost vs. Protection)

• Double Check (DC): Least expensive. Two valves, no vents, two test cocks. Buriable. For sprinkler main supply.
• Dual Check: Similar but not testable—not the same as DC.
• Reduced Pressure (RP): Highest protection, highest cost. Required for commercial/large systems. Above-ground install. Doesn't need to be above all sprinklers.

Choose based on system size, local code, and risk tolerance. The preventer cost is trivial compared to contamination liability.