The first hour: power, gas and the source
- Shut off power at the main breaker only if you can reach it from a dry spot. If you'd have to walk through standing water to get there, call an electrician to do it. Never switch power or use an electric tool while standing in water (CDC cleanup safety).
- If you smell gas, leave without switching anything and call the gas company from outside (CDC reentry guide).
- Never run a gas-powered pump, generator or pressure washer in the basement, or within 20 feet of a door, window or vent (CDC reentry guide).
- If a pipe or water heater is still leaking, shut off the water and call a plumber.
Figure out what kind of water it was
This decides most of what follows. EPA's salvage table assumes clean water, like a burst supply line. Water from outside or the sewer can carry sewage and chemicals. CDC says drywall and insulation touched by sewage or floodwater should be removed and thrown out, not dried in place (CDC cleanup safety). EPA also says not to run fans until you know the water is clean (EPA water damage table).
Many Philadelphia rowhomes are on the City's older combined sewer system, where heavy rain can push sewage back up through basement drains and fixtures (PWD backup blog). PWD asks you to call its 24/7 line while the water is still there, so an inspector can sample it and see whether it came from the City sewer. If backups keep happening, the Basement Backup Protection Program installs backwater valves for free at homes that qualify. Our basement water documentation guide covers what to photograph and record, and our floor drain guide explains that drain.
Throw out first: things that soak up water and can't be cleaned
Get these out before you spend drying time on them:
- Carpet padding, rugs, mattresses, pillows, upholstered furniture, foam items, stuffed toys, and books and papers you don't need (CDC cleanup safety).
- Ceiling tiles and wet fiberglass or cellulose insulation, even after a clean-water leak (EPA water damage table).
- Drywall and insulation reached by sewage or floodwater (CDC cleanup safety).
- Food that touched the water (CDC reentry guide).
Photocopy important papers or freeze them for freeze-drying later, and call a restoration specialist about valuable items right away (EPA water damage table).
Wear rubber gloves, boots, goggles and an N95 mask, work in pairs, and keep lifts under about 50 pounds per person (CDC cleanup safety).
Clean and dry: what can usually be saved
After a clean-water leak, EPA's table treats these as salvageable if they dry quickly (EPA water damage table):
- Concrete floors and block walls, using a wet vacuum, then dehumidifiers and fans.
- Vinyl, tile and other hard surfaces, wiped with water and mild detergent, once the floor underneath is dry too.
- Wall-to-wall carpet, only if it and the subfloor can be dried within 24 to 48 hours.
- Drywall, only if there's no obvious swelling and the seams are intact. Otherwise it comes out.
- Wood paneling, pried away from the wall so the back can dry.
Some fabrics can be saved by putting them through the laundry (EPA flood cleanup guide).
Run fans and pumps without making it worse
- If mold is already visible, gently clean what you can see before turning on fans or dehumidifiers, so they don't spread it (EPA flood cleanup guide). Point fans out a window or door, not into the house (CDC reentry guide).
- If mold covers more than about 10 square feet, or the water was sewage, EPA points you to a professional rather than a do-it-yourself cleanup (EPA mold guide).
- After a deep storm flood with soaked ground outside, the Red Cross says to pump the basement out gradually, about a third of the water per day, because draining it all at once can let soil pressure damage the walls (Red Cross cleanup guide).
- Have an HVAC technician check a wet furnace or ductwork before running it (CDC reentry guide).
- Have an electrician check anything electrical that got wet. ESFI lists outlets, switches, breakers and GFCI and AFCI devices as parts to replace, not dry (ESFI).
Don't close it up yet
No standing water doesn't mean dry. Drying usually takes days to weeks, and EPA says not to seal wall cavities or paint anything that got wet until it's dry inside (EPA flood cleanup guide). Ask a restoration contractor where they'll measure moisture and what reading means done.
Afterward, keep basement humidity under 60 percent, ideally 30 to 50 percent (EPA mold guide). Our dehumidifier drain guide covers where that water should go. A musty smell that returns means hidden wet material. If the water seeped in through the walls rather than backing up, our snowmelt leak guide helps you trace the source.