In the video, Brian opens a sprinkler valve box and walks the yard checking the system. A spring start-up catches leaks and broken heads before the watering season.

Video by Brian Huie on YouTube. Watch on YouTube

How often: Every spring
Video: 32 seconds

When should you turn sprinklers on in Seattle?

In the Pacific Northwest, the watering season usually runs April through September, and the Saving Water Partnership lists testing irrigation as a spring task. Brian's advice: check for leaks in spring so there is time to fix them before plants get thirsty.

How do you start up a sprinkler system? (Seattle Public Utilities checklist)

Close the isolation valves and test cocks on the backflow device and the mainline isolation valves, and reinstall any flow sensors.
Open the mainline valve slowly to let water back in.
Check the mainline, backflow device and valves for leaks and repair them.
Turn on the controller and rain sensor, and set a spring schedule.
Run each zone and look for leaks and broken heads.

EPA's Sprinkler Spruce-Up: inspect, connect, direct, select

Inspect: look for heads that do not pop up fully or are tilted.
Connect: check valve boxes for loose connections; water pooling between cycles can mean an underground leak.
Direct: turn heads spraying the driveway, sidewalk or walls back toward the landscape.
Select: a WaterSense labeled controller adjusts watering to the weather or soil moisture.

Safety notes

Open the main valve slowly to avoid a pressure surge.

Seattle-area notes

Seattle Public Utilities requires installed backflow assemblies to be tested every year by a Washington-certified backflow assembly tester, and Washington law requires it too. Skipping the test can bring non-compliance charges.

When to call a pro

The EPA says to call an irrigation professional certified by a WaterSense labeled program if unsure, and the Saving Water Partnership suggests a yearly check by a certified irrigation contractor.

Sources

Checked October 2026. Manufacturer instructions for a specific model come first. General information, not a substitute for a licensed professional.

From the Home Care Manual by Brian Huie, a principal broker with Compass Real Estate in Seattle.

Home Care Manual

Spring sprinkler activation and leak check