Sewer Backup in Your Basement: What to Do (and What Not to Touch)
A sewer backup is Category 3 black water and a real health hazard. The immediate safety steps, why you don't DIY it, common Utah causes, and the insurance catch.
A sewer backup is Category 3 water — "black water" — and it is a genuine health hazard, carrying bacteria, viruses, and parasites. If sewage is coming up a drain, stop using all water in the house immediately, keep people and pets away from the area, do not try to clean it up yourself, and call a professional crew with the gear to handle it safely.
First: stop making it worse
Every toilet flush, shower, or load of laundry sends more water toward the backup. Stop using all plumbing in the house until the cause is found. Don't walk through it and track it into clean areas, and shut off the HVAC if it's pulling air from the affected space.
Why you don't touch Category 3 water
Sewage isn't just dirty water. Category 3 water contaminates everything porous it touches — carpet, pad, drywall, and contents usually have to be removed and disposed of, not cleaned. Proper sewage cleanup means containment, extraction, removal of unsalvageable materials, disinfection, and verification — with the right protective equipment throughout.
What causes basement backups in Utah
- Tree roots in older clay sewer laterals — common in established neighborhoods like Holladay, Murray, and older Salt Lake City
- Grease and "flushable" wipes building up in the line
- City main backups during heavy flow
- Bellied or collapsed laterals that no longer drain
What professional cleanup involves
A crew contains the area, extracts the water, removes contaminated porous materials, cleans and disinfects every hard surface, dries the structure to standard, and documents it all for your claim.
Insurance and the backup endorsement
Here's the catch most homeowners learn too late: sewer backup is excluded by default in standard policies. Nearly every Utah carrier sells a water-backup endorsement that adds it back cheaply — and given how many homes here have basements and aging laterals, it's worth having. More on coverage in does insurance cover water damage in Utah.
Dealing with a backup right now? Don't touch it — call Keystone at (801) 948-2501. We run sewage calls 24/7 and arrive equipped to make it safe.
Questions about your specific situation? Talk to us — advice is free, 24/7.