Sprinkler and irrigation lines run exactly where concrete lifting happens — along slab edges and underneath driveways and patios. Here is how to locate them, what happens if one is hit, and how to coordinate the lift with your landscaper.
Sprinkler and irrigation lines follow the edges of your concrete. That is not a coincidence: the heads are placed to water the lawn and the planting beds, and the pipes that feed them run along the driveway, the sidewalk, and the patio to get there. In many Salt Lake Valley yards, the lines run within a foot or two of a slab edge — sometimes directly underneath a walkway or a driveway apron that was poured over them years ago.
That is exactly where concrete lifting happens. The crew drills injection holes through the slab and pumps material underneath it, and the material spreads outward from each hole until it finds the voids and lifts the slab. A line sitting just under the slab edge, or in the soil the material flows into, is in the path of the work. This is not a rare edge case — it is a normal part of lifting jobs in irrigated yards, and it is why the line question should come up in the first conversation with the contractor, not on job day.
There is a second, quieter connection between sprinklers and settlement. A sprinkler system that sprays the concrete, leaks at a head, or waters the same strip of soil every day can be the cause of the settlement in the first place — saturating and eroding the soil under the slab until it drops. If your settled slab sits next to a sprinkler head that has been watering the same spot for years, the irrigation system may be both the cause and the risk. Our drainage guide covers the water side of settlement in detail, and leaks under slabs are the same story with a different pipe.
Here is the fact that trips people up: the 811 utility locate service marks public lines — gas, electric, water main, sewer, telecom — not your private sprinkler system. Calling 811 before a lift is still a good idea (the crew may be drilling near a gas or water service line too), but it will not tell you where your sprinkler pipes are. Locating those is a homeowner-and-landscaper job.
Start with what you have. The valve boxes in the yard mark the zone valves; the heads mark the ends of the lateral lines; and the person who installed or maintains the system usually knows the layout, at least roughly. If your landscaper installed the system, they may have a layout sketch on file — ask for a copy and keep it with your house records. A landscaper or irrigation technician can also trace lines with a wire locator if the system was installed with tracer wire, or by careful probing near the slab edge.
If nobody knows where the lines are — common in older homes where the system has been modified by several owners — say so plainly to the contractor. The crew can still do the job, but they will work more cautiously around the edges, use the smallest injection points practical, and keep the injection pressure low near the slab perimeter. "Nobody knows" is the riskiest answer, so it is worth a call to your landscaper before the lift rather than after a line is hit.
It helps to know the two kinds of line, because the consequences are different:
The pipe that feeds a zone of heads. It is only pressurized when that zone runs. A break usually shows up immediately — a wet spot, a loss of pressure in that zone, water bubbling up around the slab — and the repair is a straightforward job for an irrigation tech: a section of pipe and a couple of fittings.
The pressurized pipe from the water source to the zone valves. It is under constant pressure, so a break can wash out soil under the slab and undo the lift if it is not caught quickly. A main-line break is a bigger repair and a bigger mess — which is exactly why the main line's location should be known before drilling starts.
The expensive version of a hit is the one nobody notices: a line that is nicked but not broken, leaking slowly underground for weeks. That slow leak saturates the soil under a freshly lifted slab and starts the settlement cycle all over again — the same mechanism as any water leak under a slab. This is why the system must be tested after the lift, not just assumed fine. A reputable contractor will tell you immediately if they hit a line; the repair is normally a small job, and the honesty is worth more than the pipe.
The smoothest lifting jobs in irrigated yards have three parties in the loop: the homeowner, the lifting contractor, and the landscaper or irrigation tech. Here is how that coordination usually works:
One more practical note: if the lift is on a patio or walkway surrounded by planting beds, ask the crew to lay down protection on soft or newly planted areas. The hoses, drills, and foot traffic of a half-day job can do more damage to a lawn than the lifting material ever will — and any small lawn damage from the job usually recovers in a few weeks with normal watering.
Sometimes the irrigation system is not just a risk to the lift — it is the reason the slab sank. A leaking lateral line washes soil out from under the slab, grain by grain, until a void opens and the slab drops into it. The signs are the same as any underground leak: settlement that appeared suddenly or is worsening fast, soil that stays wet along a line even in dry weather, or a strip of lawn that grows faster and greener than the rest.
If that is your situation, the sequence matters: find and repair the leak first, let the soil dry out and stabilize, then lift. Lifting over an active leak fills a void that the water will simply reopen, and you will be lifting the same slab again next season. The lifting method itself is the usual choice — polyurethane foam is waterproof and lightweight, which is what you want over soil that has been saturated — and the pricing follows the standard ranges: mudjacking $3–$8 per square foot, foam $5–$25 per square foot, most residential jobs $500–$3,000 total. See the full cost guide and the method comparison in mudjacking vs. foam. And if you are comparing lifting with starting over, lifting vs. replacement has the decision framework — though for a slab sunk by a leak, lifting after the leak repair is almost always the right call.
Yes — it is one of the first things to sort out. Sprinkler and irrigation lines commonly run right beside, and sometimes underneath, driveways, sidewalks, and patios: they follow the edges of the concrete to water the lawn and beds on either side. The injection holes for a lift are drilled through the slab, and the lifting material spreads underneath it, so a line sitting just under the slab edge or in the soil the material flows into can be damaged. Tell the contractor where your lines run before the crew arrives, and flag any heads near the work area.
Sprinkler lines are private — they are not covered by the 811 utility locate service, which marks public lines only. Locating them is a homeowner-and-landscaper job: the person who installed the system (or who maintains it) usually knows the layout, and the valve boxes, head positions, and any as-built sketch are the starting points. A landscaper or irrigation tech can also trace lines with a wire locator if the system has tracer wire, or by careful probing near the slab edge. If nobody knows where the lines are, the crew will work more cautiously around the edges and use the smallest injection points practical — but "nobody knows" is the riskiest answer, so it is worth a call to your landscaper first.
It depends on the line. A lateral line (the pipe feeding a zone of heads) will usually show up immediately as a wet spot, a loss of pressure in that zone, or water bubbling up around the slab — and it is a straightforward repair for an irrigation tech, usually a section of pipe and a couple of fittings. A main line (the pressurized pipe from the valve to the zones) is a bigger deal: it is under constant pressure, so a break can wash out soil under the slab and undo the lift if it is not caught. Either way, a reputable contractor will tell you right away if they hit a line, and the repair is normally a small job. The expensive version is a line that is nicked but not broken, leaking slowly underground for weeks — which is why the crew should test the system after the lift.
Yes. Turn the system off the day before the job and leave it off until the lift is done and the system has been tested. Dry soil is easier to work with and gives a cleaner lift, and a pressurized line that gets nicked causes far less damage when it is not actively running. It also makes a post-lift test meaningful: the crew or your landscaper can run each zone after the work and watch for pressure loss or wet spots that would signal a damaged line. If the system is on a timer, disable the timer — do not just skip a cycle.
It can fix the concrete, but only after the leak is fixed. A leaking sprinkler line washes soil out from under the slab — the same mechanism as any other water leak under a slab — and lifting over an active leak just fills a void that the water will reopen. The sequence is: find and repair the leak, let the soil dry out and stabilize, then lift. If you lift first, you will be lifting the same slab again next season. While you are at it, check the rest of the system for leaks: a line that has been leaking long enough to sink concrete has usually been wasting water for a while.
It is a good idea, especially if the system is complex or the lines are unmapped. Your landscaper or irrigation tech can mark the line locations, shut the system down properly, and come back after the lift to test every zone and repair anything that was nicked. That post-lift test is the part homeowners skip most often — and it is the part that catches the slow leaks before they wash out the soil under a freshly lifted slab. If your landscaper installed the system, they may also have a layout sketch on file; ask for a copy and keep it with your house records.
Not if the crew is careful. Polyurethane foam cures quickly and stays where it is injected, so it rarely affects anything beyond the slab edge. Mudjacking slurry can spill or wash if a hole is overfilled, but a professional crew cleans up as they go. The bigger risk to the yard is the equipment: hoses, drills, and foot traffic across a lawn that has just been watered. Ask the crew to lay down protection on soft or newly planted areas, and keep the sprinklers off until the work is done. Any small lawn damage from the job itself usually recovers in a few weeks with normal watering.
Related reading: Water leaks under slabs · Drainage & settlement · How concrete lifting works · Sealing after lifting
Tell us where your lines and heads are — or that nobody knows — and we will plan the lift around them and test the system afterward.