The drain in the basement floor gurgles, then reverses, and suddenly there is sewage where your carpet used to be. Most homeowners make the same first call, to the city, and hear some version of the same answer. The main line is fine; the problem sits in your lateral, and the lateral belongs to you. Now you are staring at two separate problems with two separate bills: the broken pipe outside and the contaminated mess inside, and a water damage restoration service only handles one of them. Knowing which is which before the argument starts saves days.
Here is the split in plain terms. Bill one pays a plumber to repair or replace the failed lateral under your yard. Bill two pays a water damage restoration service to remove the sewage, sanitize the structure, and dry your home back to safe. People confuse the two constantly, and the confusion is what lets a bad week turn into a bad month.
The two-bill problem shows up constantly in Denver, where sewer backups in aging urban neighborhoods rank among the most common causes of water damage. Restoration Logistics sees the same pattern across the metro. Older lines under Five Points bungalows and Washington Park lots have carried a century of use, and clay pipe and tree roots do not negotiate. When one of those laterals gives up, the ownership question lands on whoever holds the deed.
Follow the Pipe: Where Your Sewer Lateral Ends and the City Main Begins
Picture the pipe leaving your foundation, crossing the yard, passing under the sidewalk, and tapping into the main beneath the street. Most people assume their responsibility stops at the curb. In much of the Denver area, it does not.
Denver Water states plainly that it maintains the mains while property owners are responsible for the service lines at their address. Sanitation districts around the metro draw the same boundary for sewage, and some draw it even further out. Columbine Water and Sanitation District tells homeowners they own the sewer service line all the way to the connection at the main, including the portion sitting under the street.
That last part surprises almost everyone. A collapse twenty feet past your property line, under public pavement, can still be your pipe and your bill. Confirm the exact division point with your own utility or district, because it varies, and guessing is expensive.
Bill One: The Broken Pipe Is a Plumbing Job
The lateral itself belongs to the plumbing trade. A licensed plumber scopes the line with a camera, finds the break or the root intrusion, and repairs or replaces the pipe, sometimes by digging and sometimes with trenchless methods. The plumber pulls permits, moves dirt, and gets the pipe flowing the right way again.
What that work does not touch is your basement. The plumber leaves with the pipe fixed and the sewage still soaked into your carpet, drywall, and framing. The repair stopped the source, but it restored nothing inside the house.
Bill Two: What a Water Damage Restoration Service Does After a Sewer Backup
Sewage is not ordinary water damage, and this is where the second crew earns its bill. Restoration professionals treat backup water as grossly contaminated, which changes everything about the cleanup:
- Crews extract the waste and standing water under containment, never with a mop and bucket.
- Porous materials the sewage touched, like carpet pad and soaked drywall, usually leave the house.
- Technicians clean affected surfaces and apply antimicrobial treatments, not a quick rinse.
- Odor tracing goes to the source instead of hiding under fragrance.
- Drying finishes with documented readings for your file
Skipping this step, or doing it with a mop and bleach on a Saturday, leaves bacteria in materials you live on top of. The floor can look clean and still be a health problem. That gap between looks clean and is clean is the whole reason this trade exists.
Why the City Check Comes First, but the Sewer Cleanup Cannot Wait
There is a sensible order to the first hour. Call the city or your district and ask them to check the main, because if the blockage sits on their side, the repair bill moves off your plate. Most will send someone quickly at no charge.
Then comes the trap. Homeowners wait for the responsibility question to settle before starting anything, and the sewage sits for two or three days while phone calls go back and forth. Contamination does not pause for the answer. Run both tracks at once, let the city check the main while the cleanup starts inside, and keep every receipt and photo no matter whose pipe failed.
The Insurance Questions Hiding Behind Both Bills
This is perhaps the least fun part, and it deserves ten minutes with your agent before you need it. The two bills touch two different corners of your coverage. Ask about a water or sewer backup endorsement, which addresses the cleanup side, and ask separately about service line coverage, which addresses the buried pipe itself. Neither one is automatic on a standard policy.
Denver Water makes the same point on its homeowner responsibility page, noting that water damage may or may not be covered and telling customers to verify with their own insurer. Read your documents, ask direct questions, and get answers in writing. The worst time to learn a coverage boundary is standing in your basement in rubber boots.
The Timeline Belongs to You, Not the Argument
The who-pays question can take weeks to settle between a city, a district, an insurer, and a plumber. Your house cannot wait that long, and honestly, it should not have to. Get the main checked, get the pipe scoped, and get the contamination out while the paperwork argues with itself.
If a backup has already happened, treat the inside of your home as the urgent bill, whoever ends up paying it. A fast call to a restoration crew tonight costs less than a slow answer next week.
