REQUEST SERVICES
317-777-6489Blog
Trenchless Sewer Line Repair in Carmel, Indiana: Cast Iron Sewer Lining Without Excavation
| Project Snapshot | |
|---|---|
| Location | Carmel, Indiana |
| Property | Residential home |
| Problem | Sewer backup caused by structural damage and heavy scale buildup in cast iron pipe |
| Existing Pipe | 3″ and 4″ cast iron |
| Solution | Cured-in-place pipe (CIPP) sewer lining |
| Total Liner Installed | 31 feet |
| Project Duration | 1 day |
| Excavation Required | None |
A Carmel homeowner contacted NuFlow Indy after their sewer began backing up, preventing them from using their bathrooms, laundry, and kitchen normally. The problem had only recently started, but going several days without a functioning sewer wasn’t an option.
What Did the Sewer Camera Inspection Find?
We scheduled a sewer camera inspection for the following day and accessed the sewer through an existing outside cleanout.
Our technician first inspected downstream toward the city sewer. This portion transitioned from PVC to clay tile before reaching the city main, and we did not identify any significant problems.
The sewer running underneath the basement floor was original cast iron piping from when the home was built in the mid-1900s. Our CCTV inspection identified:
In total, approximately 31 feet of 3″ and 4″ cast iron pipe between the outside cleanout and vent stack needed to be rehabilitated.
The heavy buildup and deterioration created areas where waste and toilet paper could get caught instead of flowing freely through the sewer, contributing to the backups the homeowner was experiencing.
Could Hydro-Jetting Fix the Cast Iron Sewer Line?
We discussed two primary options with the homeowner.
- Option 1: Clean the existing pipe – The first option was to hydro-jet and mechanically clean the existing cast iron sewer. Removing the accumulated scale and debris would improve flow and could get the sewer functioning again, but it wouldn’t repair the cracks, holes, or structural deterioration we found during the inspection.
- Option 2: Line the pipe – The second option was to rehabilitate the cast iron using cured-in-place pipe (CIPP) lining, creating a new structural pipe inside the existing sewer.
For this homeowner, there was one major advantage:
Why Repair the Sewer Before the Cast Iron Gets Worse?
One of the things we explain to homeowners is that there can be a window of opportunity for trenchless sewer repair. In this case, this cast iron was deteriorated, but it was still in a condition that allowed us to rehabilitate it with CIPP lining.
For this home, traditional replacement would have meant:
- Removing finished flooring
- Saw-cutting and removing the concrete basement floor
- Excavating the old sewer
- Installing new pipe
- Replacing the concrete and then restoring the finished space
Rather than continue cleaning a structurally deteriorated pipe and risk eventually losing the ability to line it, the homeowner decided to make the long-term repair while a no-excavation option was still available.
What About Pipe Bursting?
Pipe bursting is another trenchless method that can be used to replace an existing sewer line, but “trenchless” doesn’t always mean no excavation.
For this project, pipe bursting would have required access pits to launch and receive the new pipe. Because a portion of the sewer was underneath a finished basement, that would still have resulted in excavation and disruption inside the home.
CIPP allowed us to structurally rehabilitate the existing sewer without opening the basement floor.
| Repair Method | What It Would Have Required in This Home |
|---|---|
| Traditional dig-and-replace | Saw-cutting the concrete basement floor and excavating the old sewer |
| Pipe bursting | Access pits to launch and receive the new pipe, still resulting in excavation inside the home |
| CIPP lining | No excavation – the basement floor was never opened |
How Do You Repair a Residential Sewer Line Without Digging?
Before a deteriorated cast iron sewer can be lined, it needs to be properly prepared.
| Step | Preparation Process |
|---|---|
| 1 | Hydro-jet the sewer – We started by hydro-jetting the sewer to remove debris from the pipe. |
| 2 | Mechanically clean the cast iron – We then used specialized mechanical cleaning equipment equipped with carbide-tipped chain knockers. The chains spin at high RPM to remove heavy scale and tuberculation from the inside of the cast iron. |
| 3 | Hydro-jet again – After the mechanical cleaning, we hydro-jetted the sewer again to flush the loosened material from the pipe. |
| 4 | Test and mark connections – We then water-tested the branch lines connected to the main sewer and used our camera equipment to identify and mark the location of each connection. This allows us to locate and reopen those connections after the new liner is installed. |
The goal: Restore as much of the original internal diameter and shape of the existing cast iron as reasonably possible before installing the liner.
How Is a CIPP Sewer Liner Installed?
For this project, we used a pull-in-place lining method to position approximately 31 feet of liner inside the existing 3″ and 4″ cast iron sewer.
- Expansion – Once the liner was in position, it was expanded against the inside of the existing pipe.
- UV curing – We then initiated the UV curing process. UV light cures the resin within the liner, transforming the flexible material into a rigid, fully structural pipe inside the existing sewer.
- Reopening connections – After curing was complete, we used a robotic cutter to reopen the existing branch connections serving the home.
- Flow testing – We then ran water from the connected fixtures to verify that everything was flowing properly.
Finally, we performed a post-installation CCTV inspection of the completed sewer and provided the video to the homeowner.
How Long Did the Sewer Lining Take?
Our work included:
The Result: A New Structural Pipe Without Excavating the Basement
rehabilitated
In one day, NuFlow Indy rehabilitated 31 feet of deteriorated 3″ and 4″ cast iron sewer beneath this Carmel home’s finished basement.
The new CIPP liner is fully structural with an engineered design life of 50+ years. No excavation was required, the basement floor remained intact, and the homeowner was able to return to normal sewer use after we finished.