Sprinkler system maintenance: schedule, lifespan and costs

Overview

An in-ground sprinkler system is a controller, a set of valves, buried pipes, and the pop-up heads that water each zone, with a backflow preventer on the supply to keep lawn water out of the house's drinking water. It's simple and mostly buried, and it fails one head at a time. The maintenance follows the seasons: a start-up in spring, a walk through each zone every few months, and in a cold climate a blow-out in fall that gets the water out before it freezes.

Lifespan

A sprinkler system lasts 20 to 25 years. The buried pipe lasts that long and more if it isn't frozen or dug into. The heads, the valves and the controller wear and get replaced along the way, and the backflow preventer, which sits above ground, is the first thing to break in a freeze. What shortens the system's life is water left in the pipes over winter, which splits them, and a mower, an aerator or a shovel that finds a head or a pipe.

What extends it is a proper blow-out every fall, heads kept adjusted so they aren't spraying the house or the sidewalk, and a controller set to water early in the morning when the pressure is good and the evaporation is low. The signs a system is near the end: leaks that keep appearing in the pipe, valves that stick open or closed one after another, a controller that's lost its mind, and heads of a type that's no longer made.

Maintenance schedule

The season's start and its end.

Replacement cost

Replacing a sprinkler system costs $2,500 to $6,000 for an average yard. The range depends on the size of the lawn, the number of zones, the soil, and whether the installer can pull pipe through the ground or has to trench. A smart controller that adjusts for the weather adds a little to the price and takes a lot off the water bill.

The repair-or-replace rule: a head, a nozzle, a valve, a controller or a section of pipe is a repair, and the heads and nozzles are parts an owner can change. A backflow preventer that's cracked in a freeze is a repair too, though a costly one. A system past the middle of its lifespan that leaks in several places, or whose valves and heads are no longer made, is a replacement, and the installer can often reuse the main line and the controller location.

Common problems

• Dry patches in a watered lawn: a clogged or turned head, or a nozzle spraying short. Inspect and adjust the sprinklers with that zone running.
• A geyser when a zone runs: a broken head, often from a mower. Dig it out and screw on a new one.
• A zone that won't come on, or won't shut off: a stuck valve, usually from debris in it, or a failed solenoid. Both can be replaced in the valve box.
• Heads spraying the house, the sidewalk or the street: the arc or the distance has drifted. Adjust them, since water on the siding or the foundation does damage.
• Leaks and geysers at spring start-up: pipes or heads that froze over winter. Winterize the sprinkler system every fall so it doesn't happen again.
• Water running from the backflow preventer: a cracked body from a freeze, or a failed internal part. A sprinkler company repairs or replaces it.

FAQ

How long does a sprinkler system last?

About 20 to 25 years for the buried pipe, with heads, valves and the controller replaced along the way. A yearly blow-out in a cold climate is what protects the pipe.

How much does a sprinkler system cost?

$2,500 to $6,000 for an average yard, depending on the lawn size, the zones and the trenching.

How often should sprinklers be checked?

At spring start-up, then every few months through the season, and whenever a patch of lawn goes brown.

Do I need to winterize my sprinkler system?

In any climate that freezes, yes, with a blow-out before the first hard freeze. Water left in the pipes and the backflow preventer splits them.

Why is one sprinkler zone not working?

A stuck valve or a failed solenoid in the valve box, a wiring break to that valve, or a controller fault. The valve box is the first place to look.