A High Water Bill on an Acre Lot: Finding a Buried Service Line Leak
A leak in the middle of a long service line soaks straight into the ground. There is no wet spot, no sound in the house, and no clue except the bill.
August 24, 2026 · 6 min read
Sunnyvale held on to large minimum lot sizes while the rest of Dallas County subdivided, and Parker and Lucas did the same thing in Collin County. The result is properties where the water meter is at the road and the house is a long way from it.
That single fact changes leak detection completely. On a quarter-acre lot a service line leak surfaces — you get a soft patch, a green stripe, standing water. On an acre lot with two hundred feet of buried line, the water has somewhere to go, and it goes there quietly for months.
Step one: prove which side of the house the loss is on
Before anybody starts locating, establish whether water is being lost upstream or downstream of the house shutoff. This costs nothing and it eliminates half the property.
- Turn off every fixture and appliance that uses water. Ice makers and irrigation controllers included — irrigation is the single most common false lead on a large lot.
- Go to the meter and find the low-flow indicator, usually a small triangle or dial that moves on very low flow. Note its position, or take a photo of the meter face.
- Wait 20–30 minutes with nothing running and read it again. Any movement means water is leaving the system somewhere.
- Now close the main shutoff at the house and repeat. If the meter stops, the leak is inside the house or under the slab. If the meter keeps moving, the leak is in the service line between the meter and that shutoff.
Step two: rule out irrigation
On large lots irrigation is usually teed off the service line ahead of the house shutoff, which means it will not be isolated by closing the house main. If there is a separate irrigation shutoff, close it and repeat the meter test.
A stuck irrigation valve, a cracked lateral or a failed backflow assembly can waste an extraordinary amount of water without ever producing a visible symptom, particularly if the zone in question is at the back of the property. This is worth eliminating before anyone considers digging up a service line.
Step three: locating the leak without trenching the run
Once the loss is confirmed to be in the service line, the objective is to find the point rather than excavate the length. There are a few methods and they get combined rather than used alone.
- Acoustic listening — a pressurised leak makes a characteristic noise that carries along the pipe and through the soil. Ground microphones over a traced line will localise it, though wind and traffic noise on an open acre make this harder than it is in a suburb.
- Line tracing — the run has to be located and marked before anything else is meaningful. A leak "somewhere along the pipe" is only useful if you know where the pipe goes.
- Pressure isolation — sectioning the run and testing each section narrows the search quickly where there are accessible fittings.
- Tracer gas — introducing an inert gas into the isolated line and detecting where it surfaces works when acoustic methods do not, particularly on plastic pipe, which carries sound poorly.
Repair versus replace the run
For a single failure on a line that is otherwise in reasonable condition, a spot repair is appropriate — excavate the located point, cut out the failed section, and rejoin properly.
The argument for replacing the whole run is different, and on long lines it is often the better economics. Old galvanized or aging polyethylene that has failed once will fail again, and each failure costs another detection and another excavation. Replacing a long service line can frequently be done by directional boring rather than open trenching, which matters when the alternative is a trench across a landscaped acre.
What a leak has already cost you
It is worth checking your billing history when you find one. Many utilities have a leak adjustment policy that will credit part of an abnormally high bill once a repair is documented, and almost none of them apply it automatically. Keep the invoice.
Family-owned, based in Rockwall, serving Sunnyvale, Parker, Lucas and the surrounding large-lot communities. TX Master Plumber TXM11693, TX HVAC TACLB2360E. (469) 338-5533.
Frequently asked
How much water can a buried service line leak waste?
Considerably more than people expect, because it runs continuously. A leak small enough to be invisible at the surface still runs twenty-four hours a day, and on a long line the loss simply soaks away into the ground with nothing to show for it but the bill.
Who is responsible for the line between the meter and the house?
In most North Texas jurisdictions the utility is responsible up to and including the meter, and the property owner owns everything from the meter to the house. That is exactly the section that runs the length of a large lot, which is why these leaks land on the homeowner.
Can a leak be found without digging up the yard?
Usually, yes. The point of proper leak detection is to locate the failure so that a single excavation reaches it, rather than trenching the run looking for it. On long lines a full replacement can often be bored underground rather than trenched as well.