Sewage cleanup
Of the three water categories this is the one where the water itself, not the amount of it, decides everything — what gets removed, what it costs, and whether you should be in the room at all.
CDC's position on contact
Stay out of the water. If you must enter it, wear rubber boots, rubber gloves and goggles. Wash any skin that contacts it with soap and clean water as soon as possible, and wash contaminated clothes in hot water and detergent before reusing them. Do not bathe in water that may be contaminated with sewage or chemicals.
Why this is removal rather than drying
With clean water, the aim is to get the building dry and keep as much material as possible. With sewage, the aim is to get the contaminated material out, and drying is what happens afterwards to what remains.
That inverts the usual economics. Porous material that absorbed contaminated water — carpet and pad, insulation, drywall below the water line, particle board, soft furnishings — is generally taken out rather than treated, because cleaning the surface of something that soaked it up does not address what soaked in.
What it costs, and why
On published national figures, category 3 water runs$7–$7.5 per square foot against $3–$4 for clean water — roughly double. Those figures cover drying and remediation only; putting the room back is priced separately. The full set of ranges, with the source and its date, is on the cost page.
The clock is the same, the work is not
EPA's 24 to 48 hour window does not change because the water was dirty. What changes is that two things have to happen inside it rather than one, and that the first of them — deciding and removing — cannot be hurried by equipment.
It is also the case most likely to end in a conversation about mold, simply because material that has to be opened up and removed takes longer to reach than a wet floor does. Where that line falls is covered on water damage and mold.
What to settle with your insurer
One specific thing, before anything else: whether you have sewer backup coverage. The Triple-I states that sewer backups are not covered under a typical homeowners policy and are not covered by flood insurance either; the coverage has to be bought separately or added as an endorsement. More on that, with sources, on our insurance page.
Questions people ask
Can I clean up a sewage backup myself?
This site will not tell you how to, and that is deliberate. CDC’s guidance for water of this kind is to stay out of it, and if you must enter, to wear rubber boots, rubber gloves and goggles. The cleanup involves removing material rather than cleaning it, and judging what has to go is most of the work.
Why is it so much more expensive than a clean leak?
Because more leaves the building. On published national figures, category 3 water runs $7 to $7.5 per square foot against $3 to $4 for clean water — and those figures cover drying and remediation only, with repairs priced separately.
Is a toilet overflow the same thing?
It depends on which side of the trap it came from. Clear water overflowing a bowl is one thing; water backing up from the drain line is another, and the second is treated as category 3. If you are unsure, the safer assumption is the worse one.
Does insurance cover a sewer backup?
Generally not by default. The Insurance Information Institute states that sewer backups are not covered under a typical homeowners insurance policy, and that this coverage has to be bought separately or added as an endorsement. Whether you have that endorsement is worth checking before you need it.
What about the smell afterwards?
A smell that survives cleanup generally means something porous is still in place or still wet. It is information about the job rather than a separate problem to mask.
Where this comes from
- EPA — A Brief Guide to Mold, Moisture and Your Home — Where the 24 to 48 hour drying window and the 10-square-foot rule of thumb come from.
- CDC — About Mold — Federal guidance to clean up and dry out fully within 24 to 48 hours of a flood.
- CDC — Safety Guidelines: Floodwater — What floodwater can carry, and why the advice is to stay out of it.
- CDC — Safety Guidelines: Reentering Your Flooded Home — Power, gas and when not to go back inside.
- FEMA — National Risk Index — County-level flood, hurricane and riverine risk used on the city pages.