A sewage backup is an emergency for your health and your property. Wastewater from toilets, floor drains or sewer lines carries bacteria, viruses and parasites, and it soaks quickly into floors, walls and belongings. What you do in the first few hours makes a big difference. This guide walks through the steps.
Step 1: Protect people
- Keep everyone away from affected areas, especially children, older adults, pregnant people, anyone with a weakened immune system, and pets.
- Don't walk through sewage without waterproof boots and gloves.
- Wash hands thoroughly after any contact.
Step 2: Stop the source
- Stop using water in the building: no flushing, showers, laundry or dishwashers. Every drain adds to the backup.
- Call a plumber to diagnose and fix the cause, such as a clogged main line, root intrusion or broken pipe.
- For municipal sewer backups, contact your local sewer utility.
- For septic systems, contact a septic contractor.
Step 3: Electrical safety
If water is near outlets, electrical panels, appliances or extension cords, don't enter. If you can safely reach the main breaker from a dry location, turn off power to affected areas, or call an electrician or the utility.
Step 4: Don't make it worse
- Don't use household vacuums or shop vacs not rated for contaminated water.
- Don't run fans that blow air from contaminated areas into clean ones.
- Don't use bleach mixed with other cleaners.
- Don't try to save soaked carpet, pad or upholstered furniture; materials soaked with sewage generally need removal.
Step 5: Document
- Photograph and video affected areas, water levels and damaged items before removing anything, if safe.
- Note the time you discovered the backup.
- Keep receipts for emergency expenses.
Step 6: Contact your insurer
Report the loss promptly. Many homeowners policies don't cover sewer backups unless you have a specific sewer or water backup endorsement. Commercial policies vary. Ask about coverage, deductibles and whether the insurer wants to inspect before cleanup.
Step 7: Call professional cleanup
Sewage is considered Category 3 water under the industry's water damage restoration standard. Professional cleanup generally includes:
- Extraction of sewage and water
- Removal of contaminated porous materials such as carpet, pad, drywall to above the water line, insulation and affected contents
- Cleaning and disinfection of remaining surfaces
- Drying with dehumidifiers and air movers, verified with moisture readings
- Odor control
- Documentation for insurance
Belongings
Hard, non-porous items can usually be cleaned and disinfected. Porous items soaked with sewage, such as mattresses, upholstered furniture, stuffed toys and paper goods, are usually discarded. Document items for insurance before disposal. Clothing may sometimes be laundered with hot water and detergent if lightly affected, following public health guidance.
Health concerns
Watch for symptoms such as stomach illness, fever or skin infections after exposure, and contact a healthcare provider if they occur. Wash cuts promptly and keep them covered.
Preparing in advance
Know where your main water shutoff and sewer cleanout are, keep a plumber's number handy, consider a backwater valve if your area has sewer backups, and review your insurance for backup coverage before you need it.
Businesses
Businesses should close affected areas, protect staff and customers, notify insurers, and contact professionals. Food businesses must follow health department guidance about food and surfaces that contacted sewage.
Apartments, condos and shared lines
In multi-unit buildings, a backup often comes from a shared line and can affect several units. Notify the landlord, property manager or association immediately, since they control the building's plumbing and may need to stop water use building-wide. Responsibility for cleanup and costs depends on the lease, governing documents and the cause.
Septic systems
Homes on septic systems can experience backups when tanks are full or drain fields fail, often after heavy rain. Stop water use, call a septic contractor to pump and inspect, and arrange cleanup of any interior contamination. Keep children and pets away from surfacing sewage outdoors.
Frequently asked questions
Can I clean a sewage backup myself?
Small backups on hard floors may be manageable with protection and disinfection. Anything that reached carpet, walls or large areas should be handled by professionals.
How long until we can use the room?
Often several days to a week or more, depending on drying and repairs.
Will insurance cover it?
Only if your policy includes sewer backup coverage or the cause is otherwise covered.
Should we stay in the house?
If living areas or the only bathroom are affected, staying elsewhere is safer.
Is mold a concern?
Yes, if materials aren't dried promptly. Professional drying reduces the risk.
Who pays if the city sewer caused it?
Some utilities have claim processes; ask the utility and your insurer.
Can we flush toilets once the plumber clears the line?
Yes, after the plumber confirms the line is clear and working.
Key takeaways
After a sewage backup, protect people, stop water use, call a plumber, watch for electrical hazards, avoid spreading contamination, document everything and notify your insurer. Sewage is Category 3 water: contaminated porous materials generally need removal, and professional cleanup includes extraction, removal, disinfection and drying.
Sources
- IICRC: ANSI/IICRC S500 Standard for Professional Water Damage Restoration
- CDC: Clean Up After a Disaster
This guide is general information. It is not legal, medical, environmental or safety advice. Rules vary by state and locality. For a specific situation, consult the relevant agency or a qualified professional.