Replacement, not rehabilitation
Sewer line replacement with trenchless methods in Denver is a different job from lining. Lining rebuilds the existing pipe from inside and needs that pipe to hold its shape. Replacement gets rid of the old pipe altogether and puts a new one in its place, and the trenchless way to do that is pipe bursting. It is the answer when the camera stops at a collapse, when a lateral has crushed under a driveway, when Orangeburg has gone oval, or when a property has grown past the diameter that serves it. The old pipe is not reused; it is broken apart in the ground and left as rubble around the new one.
How pipe bursting works
Two pits are opened, one at each end of the run. The entry pit is usually at the foundation wall or an existing cleanout; the exit pit is near the property line or the connection to the main. A steel cable or a string of rods is fed through the old pipe from one pit to the other. At the entry pit a bursting head, a hardened cone larger than the old pipe, is attached to the cable, and behind it the new pipe. A hydraulic pulling unit in the exit pit winches the cable in. The head splits the old pipe outward into the surrounding soil and the new pipe follows directly behind it along the same path. When the head reaches the exit pit, the new pipe runs from end to end.
The new pipe is high-density polyethylene. It comes in long coils or sticks that are butt-fused on site into one continuous length with no joints, and it is flexible enough to follow gentle curves in the old alignment. Once the pull is complete, the ends are connected to the house drain and the main with transition fittings, and the pits are backfilled.
What the day looks like
- Locates. Before any pit is dug, public utilities are marked and the owner identifies private lines: irrigation, landscape lighting, a gas line to a grill or pool heater. The bursting head displaces soil outward by a few inches, so anything crossing close to the old pipe has to be known.
- Pits. Typically a few feet square, dug by hand or with a small excavator, deep enough to reach the pipe at each end.
- Fusion. The HDPE lengths are heated and pressed together into a single pipe on the surface, then allowed to cool.
- The pull. Usually well under an hour for a residential run once the rig is set up.
- Connections and inspection. Transitions at each end, a camera pass through the new line, and an inspector's visit if the permit requires one before backfill.
- Backfill and restoration. Pits are filled and compacted, sod or concrete patched. Most jobs finish in one day.
Companies that offer trenchless sewer line replacement in Denver will show you the pit locations on the surface before the work starts, marked from the camera locate, so there are no surprises about where the openings will be.
Upsizing: bursting can install a larger pipe than the one it replaces, commonly from three or four inch up to four or six inch. If a house has added bathrooms, or a commercial property has added tenants, this is the moment to fix the diameter at the same time as the pipe.
When bursting is the wrong tool
A belly is the main one. The new pipe follows the path the head takes, and the head follows the old pipe, so a low spot stays low. If the sag is at one end, the pits can sometimes be set to pull the new pipe at a corrected grade for that section; if it is in the middle of a long run, that section is excavated and re-laid. Bursting also needs a clear path: a crossing utility within a few inches of the old pipe, a section encased in concrete, or a repair coupling made of steel can stop the head. And where the old pipe runs directly beneath a foundation footing, the soil displacement has to be evaluated. A contractor who has done a lot of bursting in Denver will raise these before you do.
Bursting compared with lining
If the old pipe still holds its shape and the camera can pass, lining is usually less invasive, since it can work through a single cleanout with no pits. If the pipe is collapsed, deformed, or needs to be larger, bursting is the only trenchless option. Some laterals get both: bursting for a crushed section near the street and lining for the sound clay under the house. The right split is visible on the camera footage, and a contractor who offers both has no reason to force one.
What you end up with
A single fused HDPE pipe from the house to the main, with no joints for roots to enter, a smooth wall that carries flow well, and a manufacturer service life generally stated around fifty years or more. Two small patches in the yard mark where the pits were, and after a season they are hard to find. For a plain description of the method and its equipment, see pipe bursting explained. For installers who have documented their process and equipment for third-party review, see verified CIPP installers serving Denver. When a line is truly beyond lining, this is how it gets replaced without a trench.
Common questions in Denver
How big are the pits for sewer line replacement with trenchless bursting in Denver?
Typically a few feet square at each end of the run, at the foundation or cleanout and near the property line or main. They are backfilled and patched the same day.
Can pipe bursting replace a completely collapsed line?
Yes, as long as the cable can be fed through or a path can be opened for it. A full collapse is one of the main reasons to choose bursting over lining, which needs a pipe that still holds its shape.
Will bursting damage other pipes or the foundation?
The head displaces soil a few inches outward, so crossing utilities must be located first and the route checked near footings. With locates done, damage is rare; without them, it is the main risk of the method.
Can I get a bigger sewer line at the same time?
Yes. Upsizing by one nominal size is routine during bursting, which makes it the right choice for properties that have added fixtures or tenants since the original line was laid.
How long does the new pipe last?
Fused high-density polyethylene has no joints and does not corrode; manufacturers generally state a service life of fifty years or more. It outlasts the clay, cast iron or Orangeburg it replaces.