Replacing a sewer line is a major maintenance job homeowners dread, mainly because of the cost. A lot of that depends on factors like the pipe material, soil conditions, depth, and how accessible the line is.
You must also budget for permits, inspections, and any repairs to your yard or driveway if there’s massive digging involved.
Traditional excavation is slower and messier, while trenchless options are quicker and less disruptive, though usually more expensive upfront.
So, how much does it cost to fix a sewer line near Boulder, CO? Here’s a clear breakdown, plus how to spot sewer problems, keep costs down, and find a contractor you can trust.
Average Cost To Replace a Sewer Line Near Boulder, CO
Based on local estimates, here are the typical price ranges of sewer line replacement in Boulder, Colorado:
| Project Scope | Price Ranges |
| Simple repair/partial replacement | $900 to $4,400 |
| Full replacement | $3,000 to $25,000 |
| Trenchless options (minimal digging) | $6,000 to $12,000+ |
| Per foot cost (varies by method) | $50 to $250 per foot |
Keep in mind: These numbers are averages. The actual cost for your property will depend on many considerations.
Key Factors That Affect Sewer Line Replacement Cost
Here’s a closer look at the most important factors that determine the final cost of replacing your sewer line:
Sewer Pipe Material (PVC, Clay, Cast Iron, ABS)
The type of pipe you have and what you’re replacing it with often drive up costs. Many older Boulder homes still have original pipes made of clay or cast iron. These older materials are heavy and take more work to remove, and all that extra labor shows up on your final invoice.
Clay pipes eventually crack and are easily invaded by tree roots, while cast iron can corrode or collapse entirely. Luckily, modern options like PVC and ABS are much lighter, smoother, and more resistant to common sewer problems.
Material choice also affects the cost of the new line itself. PVC is usually the go-to because it’s durable, easy to install, and generally the cheapest. ABS performs similarly and is also common, though it typically costs a little more.
Cast iron is still used in certain applications, but it’s much pricier and not something most homeowners choose for residential replacement anymore.
All that said, your best bet is to upgrade from clay or cast iron to PVC or ABS. Just know that the job of removing the old line will likely be a major expense in the overall project cost.
Depth and Accessibility of Sewer Line
How deep your sewer line is buried makes a huge difference in your total bill. Obviously, shallow lines need less machinery, labor, or safety measures, so they’re cheaper to remove.
Deeply buried pipes, on the other hand, mean everything takes longer: digging the trench, securing the excavation site, and eventually filling it all back in.
Accessibility is just as important. Is your sewer line running along a fence, under a patio, or beneath mature trees? Any obstacle that makes the contractor work harder to reach the pipe means an added charge.
In the worst-case scenario, contractors may have to remove and restore whatever sits on top of the pipe, which makes the project much more expensive.
Soil Conditions and Terrain
Boulder is scenic, but its terrain can be difficult to dig. Much of the local soil is packed with rocks, and it’s not unusual to find giant boulders buried here and there. After all, Boulder hugs the Rocky Mountains to the west.
Carving through stubborn earth is slow work and rough on equipment. To speed things up, specialized excavators may be brought in. Either way, expect that extra cost.
Permit and Inspection Fees in Boulder County
Like everywhere else in Colorado, Boulder requires permits and inspections for sewer work. If the work extends into public structures (like a sidewalk or the street), you’ll also need a right-of-way permit. Fees are usually determined based on the project valuation.
Inspections are mandatory, too. It’s important that your new sewer line meets all local standards and is installed correctly. While permits and inspections rarely make up the bulk of the cost, they are an expected line item on any legitimate quote you receive.
Trenchless vs. Traditional Replacement Methods
The method you choose has one of the biggest, most direct impacts on your final bill.
Traditional replacement involves digging a full trench to expose the pipe. It works well, even when the pipe is severely damaged. The downside is the sheer mess when you have to tear up yards, driveways, and anything else sitting above the sewer line in the process.
Meanwhile, trenchless options like pipe bursting or CIPP lining (more on these soon) require very minimal digging. As a result, the project is faster to complete.
Trenchless methods may cost more per foot. Yet, they often save you money overall because you avoid paying to rebuild your yard, repair concrete, or replace landscaping.
Each replacement method has pros and cons. Ultimately, the extent of damage and your property’s specific layout will determine the best solution for your sewer problem.
Extent of Damage or Root Intrusion
Another factor that affects your cost is the condition of your existing line. A slightly cracked or misaligned pipe might be fixed with trenchless repair. However, if the pipe is fully collapsed or crushed, you’re almost certainly looking at a full replacement.
Root intrusion (very common in older Boulder neighborhoods) adds complexity, especially if roots have wrapped around or grown through sections of the pipe. Severe damage is just costlier to mend.
To know how bad things are and what solution to recommend, contractors will always perform a camera inspection first.
Trenchless vs. Traditional Sewer Line Replacement Costs
As already mentioned, a huge chunk of the cost to replace a sewer line depends on the method.
Traditional excavation is the old-school approach. Crews dig a long trench along the entire length of the pipe so they can remove the old line and lay a new one. The process is messy, labor-heavy, and disruptive, especially if you have to tear through structures, lawns, or trees.
Cost-wise, you’re paying not just for the digging, but also for putting everything back together afterward. According to Home Guide, the excavation alone averages $3,500 nationwide. Restoring your property is another matter altogether.
In some cases, like when the pipe has collapsed or shifted badly, traditional replacement is the only option.
Trenchless methods are less invasive in the sense that no trench has to be dug. Instead, crews only need to dig one or two small pits and carry out the replacement there. There are two main types:
- Pipe Bursting: A new pipe, attached to a bursting tool, is threaded through the old one, shattering the old pipe as it goes. A steel pulling cable runs from the entry point (where the new pipe is fed) to the exit point, where a hydraulic machine pulls the pipe in place.
- Pipe Lining (Cured-in-Place Pipe or CIPP): A resin-soaked liner is inserted into the old pipe after it has been thoroughly cleaned. Once it cures (hardens), it creates a brand-new pipe inside the old one.
Trenchless sewer replacement costs more per foot due to the specialized equipment and materials. Still, it ends up cheaper in total since the ground stays mostly untouched, which means less surface repair work.
How to Know If You Need a Sewer Line Replacement
Plumbing issues rarely fix themselves and only get worse over time, so it’s crucial to recognize any problem early on.
If you notice any of the signs below, it’s time to call a professional for a camera inspection. This is the only way to accurately diagnose the issue and determine whether replacement is necessary.
- Multiple Slow Drains or Clogs: When multiple fixtures (e.g., the toilet, shower, and kitchen sink) are slow-draining or clogged, the problem is likely in the main line.
- Sewage Backup: Raw sewage backing up into your sink, tub, or toilet usually indicates a complete blockage or collapse in the sewer line.
- Gurgling Sounds: Strange gurgling, bubbling, or unusual noises coming from your toilet or other drains indicate trapped air caused by a blockage.
- Water Backs Up When You Flush: If flushing the toilet causes water to back up into the bathtub or shower, the mainline is most likely blocked, forcing wastewater to seek the nearest, lowest opening.
- Persistent Sewer Odor: A foul, unmistakable smell of sewage inside the home (especially in the basement or near cleanouts) suggests that sewer gases are escaping through a crack or break in the system.
Outside your home, below are indicators that you might need a new pipe:
- Green Patches of Grass: A broken sewer line can leak natural fertilizers, resulting in greener, healthier grass in an isolated spot.
- Wet or Soggy Lawn: Sewage leaks can soak into the soil, forming puddles or wet, spongy areas on your lawn, even when the weather has been dry.
- Foundation Cracks or Sinkholes: A leaking sewer line can erode the soil beneath your home’s foundation, leading to cracks in walls or floors or sinkholes in your yard or driveway.
- Rodent or Pest Activity: A sudden increase of rats, mice, and certain insects may hint that they’re using a crack or break in the pipe to access the surface.
How To Save Money on a Sewer Line Replacement
Going back to the question: how much does it cost to replace main sewer line? Well, it can easily run into the thousands of dollars. But you still can reduce your cost with these tips:
- Opt for trenchless replacement if your sewer issue allows for it.
- Get a professional camera inspection. That way, you don’t overestimate the problem and pay for unnecessary work.
- Compare quotes from different licensed contractors and find the best value.
- Inquire about permits yourself to ensure you’re paying only the exact fees.
- Take on manageable tasks, like clearing the work area of outdoor furniture, plants, garden decorations, and debris, to reduce the contractor’s man-hours.
- Make sure you know exactly what the company is responsible for restoring (e.g., backfilling and grading vs. full sod replacement).
- Check if your homeowner’s insurance covers sewer line damage. Standard coverage typically excludes issues caused by aging pipes or root infiltration, but damage resulting from a covered event, like a fire, falling objects, or explosion, may qualify.
Choosing the Right Sewer Line Replacement Company in Boulder
Sewer line replacement is a huge undertaking, so it’s worth taking a little time to vet your options. When choosing your contractor, ask:
- Do you specialize in sewer line replacement, not just general plumbing?
- Are you proficient in both trenchless and traditional excavation methods?
- Are you familiar with Boulder County permitting and inspection guidelines.?
- Do you have references and examples of past projects?
- Can I speak with previous clients to know more about your quality of work?
- Can you provide a detailed breakdown of costs?
Important: Choose a Boulder-based company as much as possible. They know the local soil conditions, weather patterns, and regulatory requirements.
Ready to start your sewer line project with a trusted local expert? Contact Septic & Sewer Boulder today for a professional consultation.
FAQs
How long does sewer line replacement take?
It mainly depends on the method used. Trenchless replacement (like pipe lining or bursting) is the quickest, usually taking only 1–3 days to finish.
In contrast, trench replacement can take 3–7 days for the installation alone. Cleanup and restoration can take a couple more days.
Does homeowners’ insurance cover a new sewer line?
No, unfortunately. Standard homeowners’ insurance generally doesn’t cover the cost of a new sewer line. Policies almost always exclude damage caused by common issues, including age, wear and tear, clogs, poor installation, or root infiltration.
Coverage is typically limited to sudden, catastrophic events (what they call a “covered peril”). Examples are damage from a fire, explosion, or vehicle impact. The only way to get coverage for the usual sewer problems is by purchasing a separate Service Line Endorsement (or rider).
What is the average lifespan of a sewer line?
The lifespan varies significantly by material. Modern pipes, like ABS or PVC, can last 100 years or more. Older materials, however, have shorter lifespans.
Cast iron typically lasts 50–75 years before it starts to corrode, and clay tile lasts 50–60 years. Orangeburg (fiber conduit) pipes are the shortest-lived, often failing completely after 30–50 years.
