The presence of an in-ground irrigation system introduces a common conflict for homeowners who also maintain their own lawn. Mowing collides directly with the need to protect the subsurface infrastructure. Sprinkler heads are sensitive components that must remain undamaged to ensure efficient water distribution. Understanding the conditions and potential fallout of a collision is the first step toward avoiding costly repairs.
Determining the Risk of Damage
The likelihood of a mower striking a sprinkler head depends on specific technical variables related to installation and equipment. A properly installed head should sit flush with the surrounding turf or slightly below grade, making it highly unlikely for a rotary mower blade to make contact. However, heads can elevate over time due to frost heave, soil erosion, or the head’s casing rising as the connection loosens, exposing components to the danger zone. A mower’s blade height setting is also a major factor, as lower settings significantly increase the risk of collision, especially with any head that is not perfectly level.
The type of mowing equipment also influences the risk profile of the collision. A heavy-duty riding mower carries more force and momentum than a manual push mower, increasing the severity of potential damage. Reel mowers, which use a scissor-like cutting action, may also interact differently with a protruding head than a high-speed rotary blade. Furthermore, the material of the head itself matters; while brass heads are more durable, plastic heads can easily shatter upon impact.
Immediate Consequences of Striking a Head
A collision between a fast-moving mower blade and a stationary sprinkler head can result in several immediate and costly negative outcomes. The most obvious consequence is the physical destruction of the head, often involving the plastic casing or nozzle shattering. A more serious result is damage to the underground connection, such as the riser or flexible swing joint, which can lead to a significant subterranean leak. This damage may be non-visible from the surface, allowing water to escape unnoticed until the next irrigation cycle.
When the system activates after a breakage, the damaged head causes massive water loss, often resulting in a geyser-like spray. This sudden pressure loss reduces the flow rate available to all other heads in that irrigation zone. Consequently, the rest of the lawn receives insufficient water, leading to dry spots and uneven turf health. The mower itself can also suffer damage; a severe impact can nick or bend the blade, requiring replacement, or jar the engine.
Techniques for Safe Mowing
Implementing practical, preventive measures before starting the engine is the most effective way to protect the irrigation system. One simple method is to clearly mark the location of every sprinkler head across the lawn using small, brightly colored flags or temporary spray paint. These visual cues serve as a constant reminder to steer the mower path around the vulnerable components.
Adjusting the mower deck to a higher cutting setting creates greater clearance between the blades and the turf surface. Increasing the cutting height substantially reduces the risk of the blade contacting an elevated head. Use a string trimmer to cut the grass immediately surrounding the heads instead of the main mower, allowing for precision trimming without exposing the head to the blade’s force.
For elevated heads, proactive adjustment is necessary to bring them level with the soil grade. Digging around the head and adjusting the soil beneath the casing corrects the height, ensuring the head retracts completely out of the mower’s path. Protective devices, such as concrete or plastic “sprinkler donuts,” can also shield the component and make the area more visible.
Steps to Take After Breaking a Sprinkler
If the unfortunate sound of a collision occurs, the immediate priority is to stop the water flow to prevent flooding and excessive waste. Locate the main irrigation system shut-off valve or the specific zone valve controlling the broken head and turn it off right away. This swift action prevents a large volume of water from erupting and eroding the soil around the damaged area.
After shutting off the water, assess the damage to determine the necessary repair. Inspect the area to see if only the threaded nozzle is broken or if the damage extends deeper to the main body or the riser pipe beneath the surface. If the break is below ground, dig around the area to expose the connection point for replacement. If the head cannot be repaired immediately, temporarily cap the broken connection to prevent dirt and debris from entering the water lines. This prevents clogging the entire zone when the system is next used.