Trenchless vs. Traditional Sewer Repair on Rancho Palos Verdes Hillside Lots

What is the difference between the two?

Traditional repair, also called open-trench or conventional replacement, digs along the pipe, removes it and lays new pipe on fresh bedding. Trenchless repair works through the cleanout and one or two small pits, either lining the old pipe from inside or bursting it and pulling new pipe through the same path.

Both are legitimate, permitted methods. The right one depends less on preference than on what the camera shows about the pipe, and on what sits on top of it.

Why does a hillside change the math?

On flat ground with open lawn above the pipe, a trench is quick to dig and easy to restore. On the Peninsula, laterals often run down a slope, under retaining walls, terraced planting, steps and long driveways. Each of those adds digging difficulty, shoring needs and restoration cost to a conventional repair. That is why owners in neighborhoods like Del Cerro and Miraleste often ask about trenchless options first.

How do they compare?

When is trenchless the better choice?

• The pipe is cracked or root-filled but still holds its shape, which suits lining.
• A section has collapsed but the run between pits is reasonably straight, which suits bursting.
• The line runs under hardscape, structures or established landscaping.
• The association or owner wants to limit disruption to shared or finished areas.

Read more about how lining and bursting work on our trenchless sewer repair page.

When does a trench make more sense?

• The camera shows a belly where water and solids pool, which no liner can correct.
• The line needs rerouting around an addition, a pool or a tree.
• The ground has moved enough to separate joints badly, and the City's rules for the area favor a particular approach.
• The run is short and shallow under open soil, where digging is simple.

Full sewer line replacement also gives the chance to add a two-way cleanout and upgrade the connection at the main.

To see where each method fits in the bigger picture, visit our Rancho Palos Verdes sewer repair guide.

What should you ask before choosing?

• What does the video show about shape, slope and joints along the whole run?
• Which sections would be lined, burst or dug, and why?
• Where would the pits or trench go, and what has to be restored?
• Which product or pipe material would be used, and what is the warranty?
• Who pulls the City permit and books inspection?

Asking every contractor the same questions makes their bids comparable. The best answers tie each choice back to the video rather than to a default preference for one method.

How long does each approach take?

Many residential trenchless jobs are finished in a day or two once the permit is issued, because there is little excavation and restoration. A traditional trench replacement usually takes longer: digging, laying pipe on bedding, waiting for the City inspection with the trench open, then backfilling, compacting and restoring surfaces. On a hillside lot with walls and hardscape, restoration alone can stretch the schedule. Either way, ask the contractor for a timeline that includes permit issuance and inspection booking, and how long the house will be without sewer service during the work.

Weather can matter too. Open trenches on a slope are best kept short during the rainy season, which is another reason some owners favor trenchless work in winter.

Trenchless vs. trench FAQs