How to Check Your Irrigation System
An irrigation system that ran perfectly last year may have developed problems over the winter—cracked heads from freeze-thaw cycles, misaligned rotors from mower contact, clogged nozzles from mineral buildup, and leaking fittings from settling soil. A thorough zone-by-zone inspection before summer heat arrives ensures every square foot of your lawn and garden gets the water it needs without wasting a drop on sidewalks, driveways, or the air.
Quick Summary
Time Required
1–3 hours
Difficulty
Easy to Moderate — DIY friendly
Estimated Cost
$0–50 (replacement heads, seals)
Zone-by-Zone Testing
The only way to find irrigation problems is to run each zone individually while you walk the entire coverage area. Problems are invisible when the system runs at 5 AM while you're asleep. Budget 5–10 minutes per zone for a thorough inspection.
Start at the controller
Use your irrigation controller's manual run feature to activate zones one at a time. If you don't know how to manually run zones, check the controller manual or look for a "manual" or "test" button. Most controllers allow you to run a single zone for a set duration. Start with Zone 1 and work through all zones in order so you don't miss any.
Walk every head while the zone runs
For each zone, walk to every sprinkler head and check that it pops up fully, sprays in the correct direction, covers its intended area without gaps, and does not spray onto hardscape. Look for heads that barely pop up (worn spring), spray erratically (clogged nozzle), or create a geyser (cracked body or riser). Mark any problems with a small flag or stake.
Check for coverage gaps
Stand at the midpoint between two heads while the zone runs. You should be getting hit by spray from at least one head, ideally from both sides (called head-to-head coverage). If there's a dry spot in the middle, heads may need their radius increased or an additional head may be needed. Dry strips between zones are the most common cause of brown patches in irrigated lawns.
Adjusting and Replacing Sprinkler Heads
Most sprinkler head adjustments take less than a minute with a flat-head screwdriver. Knowing how to make these adjustments saves you the cost of a service call and lets you fine-tune coverage on the spot.
Common Adjustments and Fixes
- Rotor head arc adjustment: Rotor heads (the ones that rotate back and forth) have an arc adjustment screw on top. Insert a flat-head screwdriver and turn clockwise to widen the arc or counterclockwise to narrow it. The left stop is usually fixed; you're adjusting how far right the head travels.
- Rotor head radius adjustment: A separate screw on the nozzle reduces throw distance. Turning it clockwise shortens the radius by up to 25 percent. Use this to prevent overspray onto sidewalks and driveways without changing the nozzle.
- Spray head direction: Fixed spray heads can be rotated by hand. Grip the nozzle (not the body) and twist to redirect the spray pattern. Some spray heads have adjustable arcs controlled by a small screw on the nozzle top.
- Replacing a damaged head: Turn off the zone, unscrew the damaged head counterclockwise from its riser, and screw on a replacement. Match the brand and nozzle type for consistent performance. Wrap the riser threads with 2–3 turns of Teflon tape before installing the new head to prevent leaks.
- Cleaning clogged nozzles: Unscrew the nozzle from the head body and rinse it under running water. Use a thin wire or toothpick to clear mineral deposits from the orifice. Clogged nozzles create weak, uneven spray patterns and are often mistaken for low water pressure.
Finding and Fixing Common Leaks
Irrigation leaks waste water, increase your bill, and can undermine foundations and hardscaping if left unchecked. Most residential leaks are minor and fixable with basic tools and inexpensive parts.
Identify leak symptoms
Water bubbling or pooling around a sprinkler head when the zone runs usually means a cracked head body or worn seal. A persistently soggy area between heads suggests an underground pipe leak. If you notice one zone has noticeably lower pressure than others, that zone likely has a significant leak diverting water.
Fix head and riser leaks
Turn off the zone and dig carefully around the leaking head to expose the riser connection. Most head leaks are caused by a cracked head body ($3–8 replacement) or a loose riser connection. Unscrew the head, apply fresh Teflon tape, and install a new head. If the riser itself is cracked, cut it below the crack and install a new riser with a coupling.
Repair underground pipe leaks
Run the suspect zone and mark where water surfaces. Dig carefully to expose the pipe at that point. For poly pipe (black flexible tubing), cut out the damaged section and rejoin with a barbed coupling and hose clamps. For PVC pipe, cut out the damaged section and glue in a new piece using slip couplings and PVC primer and cement. Allow PVC cement to cure for 2 hours before running water through the repaired section.
Rain Sensors and Smart Controllers
Technology has made irrigation dramatically more efficient. Even a simple rain sensor pays for itself quickly, and smart controllers can reduce outdoor water use by 15–30 percent compared to a basic timer.
Upgrading Your Irrigation Intelligence
- Rain sensors ($15–40): A rain sensor mounts on a fence post or eave and connects to your controller. When it detects rainfall (typically 0.25 inches or more), it pauses the irrigation schedule. Wired models connect directly to the controller's sensor terminals. Wireless models use a transmitter and receiver pair. Both types are simple to install in under 30 minutes.
- Smart controllers ($50–250): Smart controllers like Rachio, Hunter Hydrawise, or Rain Bird ESP-TM2 connect to Wi-Fi and pull local weather data to automatically adjust watering schedules. They account for temperature, rainfall, humidity, wind, and soil type. Most replace your existing controller using the same wiring and can be installed in 30–60 minutes.
- Flow sensors ($40–80): A flow sensor installs on your irrigation main line and monitors water flow in real time. It detects leaks by alerting you when flow exceeds normal parameters and can automatically shut off the system to prevent water waste and property damage.
- Soil moisture sensors ($20–50): These sensors bury at root depth and measure actual soil moisture, overriding scheduled watering when the soil is already sufficiently moist. They are especially useful in areas with variable rainfall patterns.
Pro Tips
- •Flag every head in your yard: Before the first mow of summer, walk your yard and mark every sprinkler head with a small flag. This prevents mower damage, which is the single most common cause of broken sprinkler heads. Remove flags after mowing and replace before the next mow until you know the locations by heart.
- •Keep spare parts on hand: Buy 2–3 extra heads that match your system, plus a bag of risers and Teflon tape. When a head breaks mid-summer, you can fix it in 10 minutes instead of making a hardware store trip while that zone sits dry.
- •Trim vegetation around heads: Grass and plant growth around sprinkler heads blocks spray and reduces coverage. Keep a 4–6 inch clear radius around every head. This is especially important for pop-up heads that need clearance to rise fully.
- •Check backflow preventer annually: Most municipalities require a backflow preventer on irrigation systems to protect the water supply. Have it tested annually by a certified technician as required by local code. A failed backflow preventer can contaminate your drinking water with fertilizer, pesticides, and soil bacteria.
Frequently Asked Questions
How often should I inspect my irrigation system?
Perform a thorough inspection at the start of the watering season (late spring) and again mid-summer. Additionally, do a quick visual check once a month by running each zone for a minute while you walk the yard. Sprinkler heads get knocked out of alignment by mowers, foot traffic, and settling soil, so problems develop gradually throughout the season. Catching a misaligned head early prevents a brown patch from developing in that area.
Is a smart irrigation controller worth the investment?
For most homeowners, yes. Smart controllers like Rachio, Hunter Hydrawise, and Rain Bird ESP-TM2 connect to local weather data and automatically adjust watering schedules based on temperature, rainfall, humidity, and wind. Studies from the EPA WaterSense program show that smart controllers reduce outdoor water use by 15–30 percent compared to traditional timer-based controllers. At $50–250 plus simple DIY installation, most homeowners recoup the cost within 1–2 seasons through lower water bills.
How do I find and fix a leak in an underground irrigation line?
Turn off all zones and check your water meter. If the meter is still running, you have a leak in the main supply line. If the meter is still when zones are off but you see wet spots when a specific zone runs, the leak is in that zone's lateral line. To locate it, run the zone and look for water surfacing between heads or unusually soggy areas. Mark the spot, turn off the water, and dig carefully to expose the pipe. Most residential irrigation uses PVC or poly pipe that can be repaired with a coupler and two clamps for poly pipe, or a slip coupling and PVC cement for PVC pipe. Both repairs cost under $10 in parts.
Related Guides
Set Up a Deep Watering Schedule
Water smarter with the 1-inch-per-week rule and early morning timing
Adjust Mowing Height for Summer
Why 3-4 inches is the sweet spot for summer lawn health
Mulch Garden Beds for Summer
Retain moisture and suppress weeds with proper mulching technique
Summer Maintenance Checklist
Complete 20-step guide to keeping your home in top shape all summer