What is sewage backup cleanup?
Sewage backup cleanup is the safe removal and sanitizing of a building after wastewater has come up through a drain, toilet or floor drain. Sewage is grossly contaminated, so it's treated as Category 3 water: porous materials that it touches generally have to be removed, hard surfaces have to be cleaned and disinfected, and the area has to be dried completely. It isn't a do-it-yourself job in most cases. The EPA says that for sewage or other contaminated water, you should call in a professional who has experience cleaning and fixing buildings damaged by contaminated water. For the overview, see water damage in Annapolis, MD.
Signs of a sewage backup
- water or waste coming up through floor drains, tubs, showers or toilets
- gurgling sounds from drains when you run water or flush
- several fixtures draining slowly at once, especially the lowest ones in the house
- a sewage smell in the basement or around drains
If more than one fixture is affected, the cause is likely in the main line instead of a single fixture's trap.
Why sewage is different from clean water
The CDC states that floodwater may contain sewage and that the best protection is to stay out of the water. If you have to enter it, the CDC advises rubber boots, rubber gloves and goggles, washing hands with soap and water afterward, and washing contaminated clothing in hot water with detergent. Children and pets should stay out of the area. Under the S500 standard, toilet backflow from beyond the trap is always Category 3, and clean water that sits long enough can be reclassified as it picks up contamination. See water damage categories and classes.
Who to call first
The public main or your own line?
A backup can start in the public sewer main or in the service line from your house. Ask the water and sewer utility that serves your address, which is the City of Annapolis or Anne Arundel County depending on where you live, whether there is a problem in the main. If the main is clear, a plumber can inspect and clear your own line.
Then the cleanup
The plumber fixes the cause and the restoration crew cleans up the sewage. Fixing the line first matters, because cleaning a basement that backs up again doesn't help.
Sewage cleanup and disinfection
- Extract the water. Contaminated water is pumped out with protective equipment. See water removal and extraction.
- Remove porous materials. Carpet, pad, insulation, drywall that was contacted and upholstered items are generally removed and disposed of.
- Clean and disinfect hard surfaces. Concrete, tile, framing and similar surfaces are cleaned first, then disinfected.
- Dry the structure. Dehumidifiers and air movers dry what's left. See structural drying.
- Deal with the air system. The CDC advises having an HVAC system cleaned by a professional experienced with mold before turning it on after a flood.
Insurance and sewer backup
The Maryland Insurance Administration says that if sewage backs up through pipes or drains or a sump pump overflows, homeowners coverage may apply if you bought a water or sewer backup endorsement. With the endorsement, most policies pay for damage from the backed-up water or sewage but not for repairing or replacing the pipe or drain. Maryland law requires insurers to offer this coverage, and most offer several limit options. Without it, the damage may not be covered, so check your policy now, not after a backup.
Sewage overflows and Annapolis waterways
Sewage problems aren't only indoors. In January 2026, the Anne Arundel County Department of Health warned against direct water contact on Spa Creek in Annapolis after a 9,000-gallon spill caused by a grease blockage. The warning, issued January 8 for the stretch from Hilltop Road and Boxwood Road to the end of Truxton Park, advised washing well with soap and warm water after any contact and was rescinded on January 14. It's a reminder that grease in kitchen drains is a real cause of blockages, and that health advisories for waterways are posted by the county health department.
Preventing sewage backups
- Keep cooking grease out of drains. Grease was the cause of the January 2026 Spa Creek spill.
- Flush only toilet paper, and keep wipes and hygiene products out of the toilet, even when labeled flushable.
- Have a plumber camera-inspect an older line, especially if you've had slow drains.
- Ask a plumber about a backwater valve, which can help keep sewer water out of a low house.
- Buy the water or sewer backup endorsement if your policy doesn't have it.
Sewage cleanup across Annapolis
Backups happen in every neighborhood, from older homes in Eastport and Downtown Annapolis to subdivisions in Parole and Arnold. Older lines and low-lying basements are common factors. For the whole picture of the area, see Annapolis water damage restoration; for what to do right now, see sewage backup: safety steps and next moves.
Questions to ask before you hire
- Do you handle contaminated water, and what protective and disposal procedures do you follow?
- Which materials will you remove, and how will they be documented?
- How will surfaces be cleaned and disinfected, and how will you confirm the area is dry?
- What do you recommend for the HVAC system and ducts?
- What is your MHIC license number?