Right now

A main line backup. Stop using water in the house.

Every flush, shower and load of laundry upstream sends more sewage out of the lowest drain in the house.

Nobody runs water until the line is cleared. Keep everyone out of the wet area. If sewage is near an outlet or the furnace, kill the power from a dry location or call the utility.

What is probably happening

A blockage or collapse in the main sewer line between the house and the street. Roots, grease and a broken pipe are the usual causes.
Everything that comes up is Category 3 under IICRC S500: sewage and waste line backflows are grossly contaminated by definition.
A sewage smell with no visible water can be a dry trap, a cracked vent or the start of the same backup. Treat it as a warning.

Do this in the next five minutes

Tell everyone in the house: no water, no flushing.
Close doors to the affected area and keep pets and children out.
Rubber boots, rubber gloves and goggles for anyone who goes in (CDC).
Turn the HVAC off so the air handler does not pull the air through the house.
Photograph from the doorway. Do not wade in for a better shot.
Call a plumber to clear the line, and a restoration company for the cleanup. In that order.

Do not

Do not run a shop vac on sewage.
Do not pour bleach into it. Never mix bleach with ammonia or other cleaners (CDC), and bleach does not fix a blocked line.
Do not let anyone with an open cut touch the water. Clean any exposed wound at once with soap and clean water.

Who to call

A licensed plumber

The line is still blocked. Until a plumber clears it, any cleanup will be undone by the next flush.

Also: Water damage. As soon as the line is clear, a restoration company with Category 3 experience removes and disinfects what the sewage touched. Questions for that call ›

Get a free shortlist The seven questions for this trade

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What it should cost

$99 to $1,600 to clear the line, then $3,000 to $7,000 to clean up

Main sewer line clog, average $380. Sewage cleanup, medium backup across multiple rooms.

Source: Angi, main sewer line clog repair cost, updated July 2026 and HomeGuide, sewage cleanup cost, 2026. View source

National published range, not a quote for your job. The full cost table for this trade is on the plumbing page.

Ask this contractor, on the phone, before anyone comes out

Tap each one as you ask it.

Will you run a camera after you clear it, and can I have the video?
Is it roots, grease or a broken section, and where is the break relative to the property line?
Is there a cleanout, and if not what will it cost to add one?
For the cleanup: is this priced as Category 3, and what gets removed versus cleaned?

End the call if

A quote to dig up and replace the whole line before a camera has been down it.
A cleanup company that will shampoo the carpet and leave it.
Full payment up front, or cash only.

Insurance. Sewer backup is not automatically covered. The Texas Department of Insurance says some policies cover water or sewage from outside that enters through sewers or drains; many require a separate endorsement. Check before you file.

Where this comes from

Not my problem, tap through instead Every water damage answer