Under-Slab Sewer Leak Repair in Little Elm
Sewer smell, slow drains or a damp spot that doesn't show on the water meter can mean a drain line is leaking under the slab. Call (855) 672-0175 for a licensed Little Elm plumber.
- Camera inspection shows the break on video
- Hydrostatic test confirms drain leaks
- Spot repair, tunneling or lining options
What is an under-slab sewer leak?
An under-slab sewer leak is a crack, separated joint or belly in the drain pipe that carries wastewater from your home under the foundation to the city sewer. Unlike supply leaks, it does not spin your water meter, because water only leaks when you drain it.
Because it only leaks when you use water, a drain leak can soak the soil under the slab for months before anyone notices. In Little Elm's clay, that water can make the slab heave on one side and crack tile or drywall. Sewage also brings odor and health risks.
Signs of a sewer leak under the slab
Watch for a sewer smell inside with no clogged fixture, slow drains in several rooms, gurgling toilets, damp floors near bathrooms, new cracks, or insects like drain flies. A water meter that does not move while these show up points to drains, not supply.
- Sewer odor indoorsEspecially near floor drains or baths.
- Slow drains in several roomsA belly or break holding water back.
- Gurgling toiletsAir trapped by a damaged line.
- Damp floor, normal meterClassic drain leak pattern.
- Drain flies or roachesPests drawn to leaking sewage.
- Cracks near bathsSoil swelling from wastewater.
How drain leaks are found
Plumbers confirm drain leaks with a camera inspection and a hydrostatic test. The camera shows cracks, offsets and root intrusion on video. The hydrostatic test plugs the line, fills it with water and watches the level. A drop means a leak.
- Camera inspectionA camera on a cable runs from a cleanout through the line. The plumber records the footage.
- LocateA transmitter on the camera head shows where to mark the floor.
- Hydrostatic testFill the drains with water and measure any drop over time.
- Repair planSpot repair, tunneling or a liner, with prices for each.
Smell or slow drains?
A camera inspection shows exactly what is wrong.
Sewer leak repair cost
Under-slab drain repairs in the Little Elm area usually cost $2,500 to $8,000. A single broken joint reached by a small cut sits at the low end. Tunneling to replace a long run, or replacing the main drain under the house, sits higher. Camera inspections run $150 to $500.
| Job | Typical range |
|---|---|
| Camera inspection | $150–$500 |
| Hydrostatic test | $300–$700 |
| Spot repair through slab | $2,500–$5,000 |
| Tunneling and replace section | $5,000–$12,000+ |
| Pipe lining (where possible) | $4,000–$9,000 |
Estimates for North Texas homes. Your plumber's written quote is the real price.
Why drain lines fail under Little Elm slabs
Most homes here have PVC drains under the slab, which do not rust but can crack or pull apart at joints when the clay moves. Older homes in nearby cities may still have cast iron, which corrodes over decades. Roots can also enter outside the slab.
PVC joint separation
Seasonal clay movement pulls glued joints apart or creates a sag (belly) where waste sits.
Cast iron corrosion
More likely in homes from the 1970s and 80s in Lewisville, The Colony or Plano.
Supply leak or drain leak? How to tell
A supply leak runs all the time, so your water meter moves with every tap off. A drain leak only leaks when you use water, so the meter stays still and the damp spot grows after showers, laundry or dishwashing. Odor points to a drain leak.
| Clue | Supply line leak | Drain line leak |
|---|---|---|
| Meter with all water off | Keeps moving | Stays still |
| When the spot gets wetter | All the time | After water use |
| Odor | None | Sewer or musty smell |
| Water bill | Rises | Usually normal |
| How it's confirmed | Pressure test, acoustic locate | Camera inspection, hydrostatic test |
If the meter does move, the leak is on the supply side: see finding supply leaks under the slab.
Under-slab sewer leak repair near Little Elm
Drain leaks under the slab show up across Little Elm and nearby cities, especially where clay soil movement has shifted PVC or cast iron joints.
Under-slab sewer leak repair FAQ
Does a sewer leak show on my water meter?
No. Drain lines are not under pressure, so the meter only moves when you use water. That is why a camera inspection or hydrostatic test is needed.
Is a sewer leak under the slab dangerous?
It can be. Sewage carries bacteria, and the water can shift soil under the foundation. Get it inspected soon after you notice odors or damp spots.
Can a drain under the slab be lined instead of dug up?
Sometimes. If the pipe is intact enough, a liner can be cured inside it. Badly offset or collapsed sections still need to be cut out.
Will insurance cover a sewer leak under my slab?
Some Texas policies cover access and resulting damage but not the pipe itself. Gradual leaks are often excluded. Check your policy and keep the camera footage.
How long does a drain repair under the slab take?
A spot repair takes one to two days. Tunneling to replace a longer section can take three to five days.
Smell sewage or see slow drains?
A drain leak under the slab won't fix itself. Call to get a camera inspection scheduled.