How Do I Know If My Main Sewer Line Is Broken?
Last updated October 25, 2026
The short answer
Signs Inside Your Home
The most obvious clue is when several drains in your home slow down at the same time. If the toilet, shower, and sink all drain slowly or not at all, the problem may be in the main sewer line rather than a single fixture. You might also hear gurgling or bubbling sounds from toilets or drains when water flows elsewhere, which indicates air trapped in the pipe system.
Another sign is sewage backing up into your bathtub, shower, or floor drain. This appears as dark, smelly water that rises slowly. If you notice this, stop using water in your home immediately to avoid flooding. Check for wet spots on walls or ceilings near plumbing lines, as a broken sewer pipe can leak water into your home's structure.
- Slow drains in multiple fixtures at once
- Gurgling or bubbling sounds from toilets or drains
- Sewage odor inside the house
- Water backing up into tubs or sinks
- Damp or stained drywall near plumbing
Signs Outside Your Home
A broken main sewer line often leaks into the ground outside. Look for areas of your yard that are constantly wet or spongy, even when it hasn't rained. You may also notice patches of grass that are unusually green or lush, which can indicate sewage acting as fertilizer. A sewage smell outdoors, especially near the cleanout or where the line runs, is a strong clue.
Check for visible cracks or sinking in the ground above the sewer line. If you see a depression or a dip in the soil, the pipe may have collapsed. Also, inspect the cleanout cap, usually a white or black pipe sticking up from the ground. If it's cracked or missing, water can escape and cause erosion. If you live in Layton, keep the location of your cleanout written down for quick checks.
- Wet or mushy areas in the yard
- Unusually green grass patches
- Sewage odor outdoors
- Cracks or sinking in the ground
- Damaged or missing cleanout cap
What Causes a Main Sewer Line to Break
Main sewer lines can break for several reasons. Tree roots are a common culprit, as they grow into pipe joints and cause blockages or cracks. The pipes can also shift due to soil movement, which happens after heavy rain or drought. Aging pipes made of clay or cast iron can corrode and weaken over time.
Heavy equipment or construction work near the line can crush it. Even normal ground settling can put stress on the pipe. If you have a break, you may also face water damage to your foundation or crawlspace. The pros can use camera inspections to find the exact location and cause of the break, which helps plan the repair.
How to Confirm a Break
To confirm a break, you can perform a simple dye test. Add a few drops of food coloring to a toilet or drain and flush it. If you see the colored water seeping out in your yard or near the cleanout, you have a leak. However, this test only works for visible leaks; underground breaks may not show dye.
A more reliable method is a professional camera inspection. The pros insert a small camera into the sewer line to see the inside condition. This can reveal cracks, root intrusion, or collapsed sections. If you suspect a break, call local water damage pros for leak detection services. They can also check for water damage in your home that the leak may have caused.
What to Do If You Suspect a Break
If you suspect a main sewer line break, stop using water in your home right away. This includes flushing toilets, running the dishwasher, and doing laundry. Limit water use to prevent sewage from backing up further. Then, check your yard for any obvious signs like pooling water or strong odors.
Call the pros to inspect the line and assess any water damage. They can help with emergency water extraction if sewage has entered your home. Also, contact your insurance company to ask about coverage, but keep in mind that policies vary, and your insurer decides what is covered. Check your policy to understand your options before making any repairs.
Talk to someone now
Call (801) 383-0232 any time, day or night, and describe what happened.
Call Now (801) 383-0232Frequently asked questions
Can a broken sewer line cause water damage to my home?
Yes, a broken sewer line can leak water and sewage into your foundation, crawlspace, or floors. This can lead to structural damage, mold growth, and unpleasant odors. If you notice water damage, the pros can help with extraction and drying.
How do I know if the problem is in the main line or just one drain?
If only one fixture is slow, the issue is likely in that fixture's branch line. If multiple fixtures are slow or backing up at the same time, the problem is probably in the main sewer line. A camera inspection can confirm the exact location.
Should I try to fix a broken sewer line myself?
Repairing a main sewer line is complex and involves digging, pipe replacement, and potential permits. It's safer and more effective to have the pros handle it, as they have the right equipment and experience. Attempting a DIY repair can cause more damage.