Main line backup: when it is an emergency
A single slow sink is a branch problem. A main line clog affects the lowest drains first, usually a tub, shower or floor drain, and gets worse when anyone flushes or runs the washer.
The fastest test is a cleanout. Many homes have a capped pipe near the house, along a side yard or at the front. If water stands in it, the blockage is downstream of that point. If it is dry, the blockage is between the house and the cleanout.
Stop water use
No flushing, laundry or dishwasher until the line is clear.
Find the cleanout
Look for a 3 or 4 inch capped pipe near the house or by the sidewalk.
Do not open it fully if full
A cleanout full of sewage will overflow if the cap is removed.
Keep people away
Keep children and pets away from standing wastewater.
What blocks sewer laterals
| Cause | Where it forms | What clears it |
|---|---|---|
| Tree roots | Joints in clay or concrete pipe | Root cutter, then jetting |
| Grease | Kitchen branch joining the main | Hot-water jet |
| Wipes labeled flushable | Bends and low spots | Cable retrieval |
| Debris and silt | Bellied sections | Jetting, then a camera check |
Wipes sold as flushable do not break down like toilet paper. Many sanitary districts ask residents to flush only toilet paper, and we see the same pattern in camera footage.
Main line backing up?
Call the 24/7 line. We will start with a cable, then jet and camera if needed.
Cable, jet, then camera
For a blocked lateral we start with a cable to restore flow. Because a cable can leave a coating behind, we recommend a hydro-jetting pass when roots or grease are the cause. We finish with a camera look so you can see whether the pipe is sound.
If the camera shows damage, we explain the findings and discuss sewer line repair. If the pipe is clear, we tell you so, and we suggest how often to clean.
Preventing the next backup
- Keep cooking grease out of the sink. Let it solidify in a can and put it in the trash.
- Flush only toilet paper.
- Install a cleanout if your lateral has none.
- Follow Central San's advice of an inspection or cleaning at least every other year if trees are near the lateral.
- Avoid planting water-seeking trees near the line.
What affects sewer cleaning cost
We give a clear price before work starts. Factors:
Routine maintenance cleaning is rarely covered by insurance. A sewer backup endorsement can help with damage in your home.
Want your real number? Describe the job on the call and we quote it before work starts.
Where we clean sewer lines
We clean sewer laterals in 94523 and nearby 94520 in Concord and 94517 in Clayton. The Clayton page covers that area.
Cleaning methods follow the guidelines of the sanitary district and the equipment maker. Central San advises an overflow protection device on the cleanout, installed by a licensed plumber, as a guideline for owners.
Common questions
Yes. The line is answered 24/7. Stop using water and call, and we will book the earliest visit.
Central San advises an inspection or cleaning at least every other year when trees are near the lateral. Lines with grease problems may need more.
A cleanout is a capped pipe giving direct access to the lateral. It lets us clear a blockage without pulling a toilet.
Yes. Wipes do not break down like toilet paper and collect at bends.
No. Cleaning clears blockages. A camera shows whether the pipe is broken, and repair is a separate job.
If the cleanout is dry and the main in the street is blocked, call Central San. We can help you tell the difference.
Still have a question about your situation? Call (855) 575-2890 any hour and describe what you are seeing.