Sprinkler Blowout Done in Nampa? Check the Backflow Preventer Before the First Hard Freeze — Then the Meter Test Decides the Rest

Treasure Valley sprinkler companies put the 2026 blowout booking window at October through mid-November, before the first hard freeze, when temperatures fall below 28°F — and the window is closing now. A sprinkler blowout clears water from the underground lines, but the above-ground backflow assembly and manifold sit exposed, and they are the first parts to crack in a freeze. Water pooling near the backflow preventer or the meter when the system is not running is a sign of a break. Once the system is blown out, a wet yard or a moving meter can no longer be blamed on irrigation. The post-blowout test is the meter test with irrigation off: confirm the system is fully blown out and off, turn off taps, showers, washing machine, dishwasher and ice makers, note the meter reading and whether the leak indicator is moving, wait without using water, then recheck. Movement means water is leaving the supply line somewhere. A blowout does not protect the house supply line: it clears irrigation lines only, and the house supply line is a separate line from the meter to the house. The November 16–17 nights reach 36°F and 30°F, cold enough to freeze an exposed line but not yet a hard freeze — and that is exactly what the blowout is timed against. Nampa Water Leak Detection Pros covers underground and water line leak detection for Nampa homes in ZIPs 83651, 83686 and 83687, with 24/7 call help. The service is water and plumbing leak detection only — not gas, not roof, not pool. Call (208) 544-9851, open 24/7. Website: https://waterleakdetectionnampaid.com/ — guide: https://waterleakdetectionnampaid.com/blog/sprinkler-blowout-backflow-preventer-nampa/

Nampa Water Leak Detection Pros, 1023 15th Ave S, Nampa, ID 83651. Phone (208) 544-9851. Open 24/7. Website: https://waterleakdetectionnampaid.com/