Sewage coming up through a drain, toilet or floor drain is one of the more alarming kinds of water damage, and also the one where doing the wrong thing carries the most health risk. The right response is mostly about staying safe, finding out where the blockage is, and getting trained help for the cleanup. This guide covers what to do first and what comes next. For the wider picture, see our page on sewage and water damage help in Annapolis.
First, treat it as hazardous
The CDC says floodwater may contain sewage, along with household, medical and industrial waste, and that the best way to protect yourself is to stay out of the water. The same caution applies to a backup inside the house. If you have to enter the water, the CDC advises rubber boots, rubber gloves and goggles, washing your hands with soap and water afterward, washing contaminated clothing in hot water with detergent, and keeping children away from the area. People with open wounds should avoid the water altogether.
Safety steps, in order
Stop adding water
Don't flush, run taps, use the dishwasher or run the washing machine. Every gallon you add can end up on the floor.
Keep people and pets out
Close off the area and keep children and pets away.
Stay clear of electricity
The CDC says never to turn power on or off, or use electric tools, while standing in water. Call an electrician if water is near outlets or the panel.
Photograph the damage
Take photographs from a distance before anything is cleaned or moved.
Call a plumber and a cleanup professional
The plumber finds and clears the blockage, and a professional experienced with contaminated water handles the cleanup. See sewage backup cleanup.
Call your insurer
Ask whether you have a water or sewer backup endorsement and what documentation is needed.
Is it your line or the public main?
A backup can start inside the house, in the service line between the house and the street, or in the public main. A few clues help narrow it down.
- If only one fixture is affected, the problem is probably in the line serving it.
- If several fixtures back up, especially the lowest ones, the main line is more likely involved.
- If neighbors have the same problem, the public main may be involved.
Ask the 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 your own line, often with a camera. Fix the cause before cleaning, because cleaning a basement that backs up again doesn't help.
How cleanup works
Sewage is Category 3 water, the most contaminated category. The EPA says to call in a professional who has experience cleaning and fixing buildings damaged by contaminated water, and the work usually follows a standard order.
- Extract the water using equipment and protective gear suited to contaminated water.
- Remove porous materials that the water touched, such as carpet, pad and insulation, and generally any affected drywall.
- Clean and disinfect hard surfaces and the framing that stays.
- Dry the structure with air movers and dehumidifiers, with moisture readings recorded. See structural drying.
- Deal with the air system. The CDC advises having the HVAC system cleaned by a professional experienced with mold before turning it on after a flood.
What gets thrown away
| Material | Typical outcome after sewage |
|---|---|
| Carpet and pad | Removed. Guidelines built on the S500 standard say carpet wet with Category 3 water must be removed at any time. |
| Insulation | Removed and replaced, since it can't be adequately dried. |
| Drywall that was contacted | Generally cut out and replaced after the wall cavity is cleaned and dried. |
| Upholstered furniture and mattresses | Commonly discarded, since they can't be reliably cleaned. |
| Food and anything porous that touched the water | Discarded. The CDC says to throw out food that contacted flood or storm water: "when in doubt, throw it out." |
| Concrete, tile and sound framing | Cleaned, disinfected and dried. |
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 the 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. If you don't have it, the damage may not be covered, so it's worth checking before a backup happens. See homeowners insurance and water damage in Maryland.
Why backups happen, and a local example
Common causes include grease and wipes blocking lines, tree roots, damaged or aging pipes and heavy rain overloading a system. A recent Annapolis example involved grease: on January 7, 2026, a grease blockage caused a 9,000-gallon sewage spill into Spa Creek. The Anne Arundel County Department of Health advised against direct water contact on the affected stretch, from Hilltop Road and Boxwood Road to the end of Truxton Park, and asked anyone who touched the water to wash well with soap and warm water. The warning was rescinded on January 14, 2026.
- Keep cooking grease out of drains, and put it in the trash instead.
- Flush only toilet paper, and keep wipes out of the toilet, even when labeled flushable.
- Have a plumber camera-inspect an older line, especially after repeated slow drains.
- Ask about a backwater valve if you have a low basement.
- Buy the water or sewer backup endorsement if your policy lacks it.
Sewage backups across Annapolis
Backups occur in every neighborhood. Older lines in Eastport and Downtown Annapolis, low-lying basements and newer subdivisions in Parole and Arnold each have their own risks. If you live outside the City, find out whether your home is on public sewer or a septic system, because that changes who fixes the problem.