Minute by minute

Right away
Tell everyone in the house to stop using water: no flushing, showering, dishwasher or laundry. Turn off a washing machine mid-cycle if it is draining.
First 5 minutes
Close doors to the affected bathroom or laundry room. Move pets elsewhere. If anything is still running or a supply line is leaking, close the main water shutoff.
First 15 minutes
Take photos and short videos of where the water came up, how far it spread and anything it touched. Note the time.
First 30 minutes
Contact a licensed plumber. Describe which fixtures backed up and whether you have an outdoor cleanout. Ask for the contractor's CSLB license number.
Within the hour
Call your homeowners insurance or check your policy for sewer backup coverage. Move dry belongings away from the wet area.

Why stopping water use matters so much

A backup does not drain away on its own while the main line is blocked. What you see on the floor is water that was already in the system, plus anything added since. A single flush can add over a gallon, a shower many more, and a washing machine drain cycle pushes a large surge through the pipe in a minute or two.

Households often make a backup worse without meaning to: someone flushes out of habit, a dishwasher starts on a timer, or an irrigation system tied into a utility sink kicks on. Put a note on each toilet lid if you need to, and check for any appliance that runs on a schedule.

Helpful versus harmful in the first hour

Helpful

  • Stopping all water use in the house
  • Closing off the room and ventilating it
  • Wearing rubber gloves and boots if you must enter
  • Photographing everything before cleaning
  • Checking the contractor's license at cslb.ca.gov

Harmful

  • Pouring chemical drain opener into a backed-up line
  • Forcing open a cleanout cap that is under pressure
  • Using a household vacuum on sewage
  • Mopping sewage into other rooms
  • Running the washer to see if it clears

Have these ready when you call

  • Your address and the age of the house, if you know it.
  • Which fixtures backed up and which still drain.
  • Where the outdoor cleanout is, or that you could not find one.
  • Photos of the backup and of the cleanout area.
  • Whether you rent, own, or live in a unit with a shared building sewer.

Renters and condo owners

If you rent, tell your landlord or property manager immediately and in writing, even if you also call a plumber. In a condo or townhome, call the HOA or management company: several units may share one building sewer, and who handles it depends on your governing documents.

Common questions

Should I turn off the main water valve?

It is not required for a pure drain backup, but it is a good idea if anything is still running, a supply line is leaking, or you cannot stop people from using water.

Can I clean up before the plumber comes?

Photograph first. Light cleanup of hard surfaces with gloves is fine, but avoid spreading sewage, and expect more water if anyone uses a drain before the line is cleared.

Is it an emergency if it stopped rising?

The line is still blocked. As soon as water is used again it will come back up, so treat it as urgent even if the floor looks stable.

General information for Fullerton, not a quote or professional advice. In an emergency, call 911.