Your sprinkler system is trying to tell you something

Baffled by spots, stripes or other odd patterns in your lawn? Before you chalk it up to alien crop circles, you might want to inspect your irrigation system.

Summer in Texas always means high heat, little precipitation and grass that fades from green to yellow over the season. But when you’re using in-ground sprinklers, you may also see subtle patterns appearing like crop circles across the lawn.

These can be an indicator of a malfunctioning irrigation system.

Learning how to recognize these patterns can help you diagnose the problem, which is especially important during drought — and watering restrictions — when irrigation efficiency is crucial.

Look for these telltale signs:

  • Circles or semi-circles of green grass surrounded by struggling grass: a symptom of low pressure on a spray zone. Low pressure reduces the distance that each head can “throw” water, leading to patchy, inefficient distribution. Line breaks, broken sprinkler heads, or failing irrigation control valves are all causes of low pressure.

  • A ring with a dot in the middle: produced by low pressure in a rotor zone. The lower pressure prevents the stream of water from fanning out and covering the area evenly. Again, this can be cause by line breaks, a broken rotor head, or failing irrigation control valves.

  • A single stripe of green or radiating stripes and spots radiating out from a central spot: caused by a stuck rotor or a stuck multi-stream rotor. When working properly, rotors sweep back and forth applying water evenly across the area they cover; when they get stuck, they only apply water in a stream at the point where they’re jammed.

  • Irregular green spots. Even if a zone is working properly, issues with individual sprinkler heads can reduce the efficiency of the entire zone. Blocked sprinkler heads, clogged heads, and sunken heads can all cause these strange patterns. Clogged heads contain mud or debris that simply needs to be cleared. Sunken heads that can’t clear the grass just need to be adjusted or replaced with a taller pop-up so the spray pattern can reach above the sod.

  • Entire zone. If an entire section zone doesn’t seem to be getting any water, there could be a few different problems. Zone valves can stick shut or be disconnected from the controller and fail to open. But if you notice a dry zone with one big wet spot, this is the classic symptom of a broken lateral line.

During Stage 2 watering rules, it can be easier to spot these problems because irrigation is mostly running in daylight. But it’s always good practice to watch your system run once a month. The telltale patterns provide clues on where you need to check. Often there are several factors at play.

A great place to start is with a free irrigation consultation. We’ll check the system for potential problems and suggest ways to conserve water. Give us a call at 210-704-SAVE to schedule yours today!

Picture of Cleveland Powell
Cleveland Powell
Cleveland Powell is a conservation planner for SAWS. He is enthusiastic about grass taxonomy and milkweed propagation. In his free time, Powell enjoys hiking around area parks in search of intriguing bugs, birds and plants.
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