Cleaning up after a sewage backup, by the CDC and EPA rules
Updated October 30, 2026 · 2-minute read · Old House Sewer Lines
Sewer backup cleanup starts with protection: CDC says to wear rubber boots, rubber gloves and goggles whenever sewage is involved, and to keep children and pets out of the area until the work is finished. EPA adds an N-95 respirator, long pants and long sleeves.
Before anyone wades in, the power question has to be settled. CDC rules out touching breakers, switches or electric tools while your feet are in water, and to have an electrician cut the main if reaching it means stepping into standing water (CDC). The first hours after a backup, including that electrical check and a possible gas smell, are covered in sewage in the basement: what to do first.
Speed and what has to go
CDC tells households to clean and dry the home quickly, within 24 to 48 hours if possible. Anything that cannot be cleaned or dried fast should be thrown away, and CDC lists mattresses, carpeting, carpet padding, rugs, upholstered furniture and paper products. Drywall and insulation that sewage has touched must be removed and discarded. EPA's Region 2 guidance takes the same line on soft or porous items that cannot be disinfected (EPA Region 2).
Hard surfaces get washed first with hot water and laundry or dish detergent, per CDC. Disinfecting comes after. Where a ratio is given, CDC and EPA use 1 cup of unscented household bleach in 5 gallons of water for surfaces (CDC bleach flyer). EPA separately says to disinfect waterproof boots and gloves afterwards in half a cup of bleach per gallon. Follow the label on the bottle you use.
People and clothing
EPA says any wound that touches sewage or flood water should be washed and disinfected right away. CDC says to wash everything worn during cleanup in hot water and detergent, separately from other laundry. Hands get washed every time the gloves come off.
EPA's first piece of advice is administrative: contact local officials about professional help and referrals to qualified contractors, and document the damage for insurance before it is hauled away. Large jobs are often better handed to a cleanup firm. A standard New York homeowners policy may not pay for any of it; the insurance item explains the add-on that does.
Stopping the next one
Cleanup does not fix the cause. If the lateral was clogged, a licensed plumber clears it and, ideally, runs a camera to see why; sewer camera inspection covers what that shows. If the backup came during a storm, the town's main may have been overloaded, and FEMA describes backwater valves as the device that lets wastewater leave while blocking it from coming back (FEMA). The options are compared on the backups topic page.
Key facts
- CDC: rubber boots, rubber gloves and goggles when sewage is involved; keep children and pets away (CDC).
- CDC: clean and dry within 24 to 48 hours where possible, and discard drywall and insulation touched by sewage.
- EPA adds an N-95 respirator, long pants and long sleeves, and says to wash and disinfect any wound that touches sewage (EPA Region 2).
- CDC and EPA sanitizing ratio for surfaces: 1 cup unscented bleach in 5 gallons of water (CDC).
- Never mix bleach with ammonia or any other cleaner (CDC).
- No generators or pressure washers inside the home or basement (CDC).