Turning Your Sprinkler System Back On in Spring

Spring startup is when many sprinkler problems come to light. Parts that sat through winter, cracked in a freeze or got bumped by yard work all show up once the system is pressurized again. Taking a little care with the startup can prevent water hammer damage and catch problems early. This article walks through a safe spring startup for a Fort Worth system.

When to Start

Wait until the risk of hard freezes has passed. In Fort Worth, that is usually sometime in March, but late cold snaps can happen. Warm-season grasses like St. Augustine, Bermuda and zoysia do not need much water while they are still dormant or just waking up, so there is no rush. Spring rains often cover the lawn’s needs early in the season.

Step 1: Check the Controller

• Replace the backup battery if the controller uses one.
• Check the date and time, including AM and PM.
• Review the program. Make sure watering days match your address: Wednesday and Saturday for even-numbered addresses, Thursday and Sunday for odd. No irrigation on Monday or between 10 a.m. and 6 p.m.
• Set the seasonal adjust low for early spring.

Our controller programming guide covers the details.

Step 2: Inspect the Backflow Preventer

Before turning on any water, look at the backflow preventer for cracks, bulges or damage. Remove any insulated cover. Close the test cocks if you opened them to drain. If the assembly looks damaged, do not pressurize it; arrange a repair. Our article on a leaking backflow preventer explains what to look for.

Step 3: Pressurize Slowly

Opening valves quickly sends a surge of water through empty pipe, which can cause water hammer and stress fittings.

1. Open the irrigation isolation valve slowly, a quarter turn at a time.
2. Open the backflow preventer’s inlet shutoff slowly.
3. Wait for the assembly to fill, then open the outlet shutoff slowly.
4. Watch the assembly for a minute or two for leaks.

Step 4: Check for Leaks on the Mainline

With the supply side pressurized and no zones running, check the water meter. If the leak indicator moves with all water use off, there may be a leak on the mainline or at a valve. Our water meter leak test explains how.

Step 5: Run Each Zone

Run each zone manually for a few minutes. On the first run, some air and debris may come out of the heads. Watch for:

• Heads that do not pop up or retract
• Geysers or bubbling
• Heads spraying concrete, fences or the house
• Weak or uneven spray
• Rotors that do not turn
• Dry gaps in coverage
• Water in valve boxes

Mark problems with flags. Our zone-by-zone system check has a full list.

Step 6: Clean Nozzles and Filters

Debris often gets into heads over winter. Clean clogged nozzles and screens. On drip zones, clean the filter and flush the lines by opening the end caps.

Step 7: Test the Rain and Freeze Sensor

Make sure the sensor is set to active, press its test button or wet it, and confirm the system stops. See our article on rain and freeze sensors.

Step 8: Adjust and Repair

Fix the easy things right away: turning heads, cleaning nozzles, straightening tilted heads. Note bigger problems for repair. After a winter with hard freezes, check especially for cracked parts. Our guide to freeze damage after a hard freeze covers what to look for.

Early-Season Watering

In early spring, lawns usually need little supplemental water. Let spring rain do most of the work. Increase run times gradually as temperatures rise and grass greens up. Watering heavily too early can encourage weeds and disease without helping the grass much. A spring checklist that covers mowing height, fertilizer timing and weed control goes along well with the startup.

Spring Yard Work and Your System

Spring is when many people install new beds, fences and patios. Before digging, mark your sprinkler heads, pipe routes and valve boxes. Call 811 for public utilities. Sprinkler lines and wires are private and are not marked by 811.

Watch for Water Hammer

Water hammer is the banging or knocking sound pipes make when flowing water stops or starts suddenly. It is most common during startup, when air trapped in empty pipe is pushed out and water rushes in behind it. Opening valves slowly is the main defense. If you hear banging when zones start or stop during normal use later in the season, it can point to pressure that is too high, a valve closing too fast or loose pipe. Repeated hammering stresses fittings and can lead to leaks, so it is worth having a technician look.

Timing Around Spring Storms

Spring in North Texas often brings heavy rain, strong wind and hail. There is little point running the system during a wet week. Let the rain sensor and your own judgment keep the system off when the soil is already moist. After storms pass, walk the yard for heads damaged by fallen limbs and for debris clogging nozzles.

Keep a Startup Record

Write down what you found during startup: which heads you replaced, which zones had problems, and any leaks you fixed. Next spring, compare. Heads that break every year in the same place may need to be moved. Zones that always need work may have a deeper problem worth fixing once instead of patching each year.

When to Call a Technician

If the backflow preventer is damaged, you find leaks, or zones will not run, our sprinkler repair service can handle the spring startup and any repairs.