Sewer Line Replacement and Trenchless Options in Metro Denver

Is the line worn out, or just clogged?

A sewer that backs up is not automatically a sewer that needs replacing. Grease, wipes and a few roots can stop a healthy pipe cold. Replacement starts to make sense when the trouble is the pipe itself. Cost guides and plumbers point to the same set of warning signs:

• Several fixtures slow down at once, rather than one sink or one tub
• The tub or shower water rises when a toilet is flushed
• Gurgling at floor drains in the basement
• A sulfur smell, or a soggy or sunken strip of lawn along the sewer route
• Backups that return weeks after the line was cleared

None of those prove a broken pipe. They justify a camera inspection of the lateral, which is the only way to see cracks, offset joints, root entry and sags. Ask for the video file and a written footage count to each defect. One bad joint usually points to a targeted sewer repair. Defects scattered from the house to the street point toward replacing the run.

Which part of the pipe is yours?

Before comparing methods, find out what you are responsible for. Metro Denver does not have one rule, because sewer service comes from cities, a consolidated city-county, and a long list of water and sanitation districts. A few examples from local utility rules:

• Arvada: owners are responsible for the sewer service line from the house to the city main, and the city does not cut, clean or televise residential service lines.
• Westminster: property owners maintain the lateral to the city main, including the tap.
• Longmont: the city maintains the mains, and the sewer service line belongs to the property owner.
• Superior: the Superior Metropolitan District makes homeowners responsible for the whole lateral to the main, including sections under the street right-of-way.
• Commerce City area (South Adams County Water and Sanitation District): the district asks you to call during a backup so it can help tell whether the blockage is in its main or your private line.

In the City and County of Denver, Wastewater Management in the Department of Transportation and Infrastructure runs more than 1,500 miles of sanitary sewer, and Metro Water Recovery treats the flow for most of the metro area. Call Wastewater Management about your address before anyone digs near the street, because the point where your pipe meets the public main is where ownership questions come up.

What are the ways to replace a lateral?

Both cost guides make the same point: trenchless methods are not a fit for pipe that has collapsed or lost its slope. If the camera shows a belly holding water, lining just reproduces the belly in new material. The Denver sewer replacement page covers how plumbers choose among these.

What does sewer line replacement cost?

National averages are a starting point, not a Denver quote. Here is what two established cost guides reported for 2026:

Surface restoration is where trench jobs get expensive. Angi lists breaking up and restoring a concrete slab section at $300 to $350 per linear foot and landscaping repair at $4.50 to $12 per square foot. A long lateral under a driveway, a deep line, or a tie-in under the street will land well above the averages. For a wider view of how plumbing work is priced here, see what plumbers charge in Denver.

What usually rules out a trenchless job?

1. Collapse. If the pipe has caved in, there is nothing for a liner to follow and a bursting head may not get through.
2. Grade problems. Sags that hold standing waste need the pipe re-laid at the right slope.
3. Hard bends or fittings. Bursting works best on straight runs between pits.
4. No access. Lining needs a cleanout or opening at each end. If the house has no usable cleanout, adding one is part of the job.
5. A failing building drain. If the cast iron under the basement floor is also failing, fixing only the yard section leaves the problem inside.

Permits and locates before anyone digs

Sewer work usually needs a permit, and the rules vary by city. Broomfield, Castle Pines and Lone Tree, for example, all list sewer line repair as permitted work. Ask the plumber to name the permit and the inspection in the written quote. If your home is in Broomfield or near the Lone Tree area, the city building division can confirm what applies to your address.

Colorado 811 asks that anyone digging contact it first, and the request costs nothing, but it marks public utility lines only. Your sewer lateral, a sprinkler system, or a gas line to a grill are private and will not be painted. Tell the crew where those run.

Why older Denver houses come up so often

Census survey data put the median Denver home at 1975, and about 55.5% of the housing was built before 1980. Houses from those decades can still have clay laterals in the yard and cast iron drains inside. Both can last a long time, but joints loosen, roots find gaps, and cast iron scales up. This Old House puts modern sewer pipe life at 50 to 100 years overall, with PVC lasting 100 years or more. A line on its original material in a mid-century bungalow has used much of that span.

The same pattern shows up across older parts of the metro. Arvada owners, for instance, handle their own laterals entirely, so it pays to read how Arvada sewer replacements work before you call. North of Denver, many Westminster sewer repair jobs start with the same question of where the private line ends.

How should you compare quotes?

• Is the method named, with a reason the others were ruled out?
• How many feet are being replaced, from what point to what point?
• Does the price include permits, the tie-in, cleanouts and a final camera pass?
• What surface restoration is included: grass seed, sod, concrete, asphalt?
• What pipe or liner material goes in, and what warranty covers it?

If a quote recommends full replacement but never shows you footage, ask for it. If a quote offers repeated jetting for a pipe the video shows is broken, ask why. Our guide on jetting versus snaking a drain explains when cleaning helps and when it only delays a repair. If a backup is happening right now, have the line cleared with water jetting service or a cable machine first, then schedule the camera once it is flowing.