The shower drain gurgles, then brown water rises around your ankles. Or the toilet will not flush and the lowest drain in the house starts to fill. A sewage backup is one of the few water emergencies where the best first move is to leave the room and keep everyone out of it. Our line is answered 24/7, and calling is the second step, not the first.
Do not run any more water. Every flush, load of laundry or dishwasher cycle sends more wastewater toward the same blocked line. Close the doors to the affected rooms and keep children and pets away from the floor.
The first calls, in order
Stay out and stop adding water
No flushing, no sinks, no washer. If water is near outlets or the panel, call 911 or the utility before anything else.
Check the street
Look at the sewer manhole cover in front of the house and ask a neighbor. Several homes backing up, or a manhole overflowing, points to the city main.
Call the right pipe owner
For the city main, call the LA Sanitation 24-hour Customer Care Center at 1-800-773-2489. For a blockage in your own lateral, call a licensed plumber.
Photograph before cleanup
Take photos and video of the water line, the floor and any damaged belongings before anyone moves anything.
Call a restoration crew
Sewage cleanup needs protective gear, extraction and disinfection, which is the work behind our emergency water removal line. You hear the scope and cost before work begins.
Who owns which pipe
| Pipe or section | Who owns and maintains it | Who you call |
|---|---|---|
| Public sewer mainline in the street | The City of Los Angeles | LA Sanitation, 24-hour line 1-800-773-2489 |
| Lower lateral, from the property line to the middle of the street | The property owner | Your own plumber, who can camera the line |
| Upper lateral, from the building to the property line | The property owner | Your own plumber |
| Indoor drain lines and fixtures | The property owner | Your own plumber |
| Wet floors, walls and belongings after the backup | You, or your insurer if covered | A restoration crew, then your insurer or agent |
That second row surprises many owners. The lateral does not stop at your fence. In Los Angeles the owner carries the whole pipe, out to the center of the street. A plumber with a camera can show whether the blockage is in your pipe or in the main, and that photo or video is useful proof when you talk to the city or your insurer.
Why wastewater is treated differently from a broken pipe
Restoration standards sort water into three categories. Clean supply water is Category 1. Used water from appliances can be Category 2. Sewage is Category 3, the most contaminated. Treat everything the wastewater touched as unsafe to handle without gloves, boots, eye protection and a mask.
Cal OES advises goggles, gloves and boots around floodwater because of the contaminants it carries, and the same caution applies indoors. Drying alone does not clean wastewater. After extraction, hard surfaces are cleaned and disinfected and the structure is dried with air movers and LGR dehumidifiers, following ANSI/IICRC S500. Our flood damage restoration service covers this kind of contaminated loss.
What gets removed and what gets cleaned
Carpet and pad
Pad soaks up wastewater and cannot be cleaned through. Carpet and pad that sat in sewage are usually removed and replaced.
Drywall and insulation
Porous materials that wicked wastewater above the floor are cut out, often a foot or more above the visible waterline, depending on meter readings.
Hard flooring and baseboards
Tile and sealed surfaces can often be cleaned and disinfected. Wood, laminate and the cavity behind baseboards need a closer look.
Belongings
Hard items such as glass and metal can be cleaned. Porous items such as books, cardboard, upholstery and stuffed toys are usually discarded after you photograph them.
The common thread is porous versus non-porous. A porous material absorbs the water, and you cannot reach the contamination inside it. That is why technicians use moisture meters and thermal imaging cameras to find how far wastewater went, then cut to the dry edge rather than guessing.
Do not scrub it yourself
Mops and wet vacs spread wastewater to new surfaces and carry it into other rooms. Leave extraction to a crew with the right equipment, and keep the area closed until they arrive.
What causes most backups, and what a backwater valve does
Most backups are slow in the making. Tree roots grow into joints in old clay or cast iron lines, and cooking grease poured down the sink hardens inside the pipe. Both narrow the line until one day it closes. Homes in Woodland Hills and Winnetka see the same pattern with mature trees along the street.
A backwater valve is a one-way valve on the lateral that closes if wastewater flows backward. It matters most when your lowest fixture sits below the street manhole cover, because gravity then pushes the city's overflow toward your drains. Ask a plumber whether yours does, and expect a permit for the install. Questions about restoring a flooded home can be answered at (818) 337-2642.
What Los Angeles Sanitation says about backups and who is responsible
On its sewer system page, LA Sanitation and Environment states that the city owns the public mainline and that owners must maintain and repair their entire lateral, from the building to the middle of the street. It adds that over 50% of backups come from tree roots and from fats, oils and grease. Most backups are therefore preventable with grease habits and a camera check of an older line.
The page also says a home whose lowest fixture sits below the street manhole cover may need a backwater valve, with the permit coming from LADBS. The agency's 24-hour Customer Care Center number is 1-800-773-2489. Its wet weather page files sewage overflow under non-emergency 311 reports and keeps 911 for threats to life and safety, so use the 24-hour line for an active backup.
Source: LA Sanitation and Environment, sewer system page and wet weather preparedness page
Insurance, in plain terms
Sewer or water backup is usually a separate coverage question from a burst pipe. Check your policy for water backup coverage, and ask your insurer or agent whether you carry it before the cleanup bill arrives. The California Department of Insurance renters guide lists water backup among the damage a renters policy can include, which tells you it is worth asking, not that you have it.
Keep your photos, the plumber's findings and every receipt. Hold off on discarding damaged belongings until your adjuster has weighed in, and photograph anything that has to go.
Questions about sewage backups
Is a sewage backup in West Hills the city's problem or mine?
It depends where the blockage is. Los Angeles owns the public mainline in the street, and you own the entire lateral, all the way to the street's midpoint. If neighbors are backed up or the manhole is overflowing, call LA Sanitation at 1-800-773-2489. If only your drains are affected, have a plumber camera the lateral.
Do I need a permit for a backwater valve in West Hills?
LA Sanitation says backwater valve permits are issued by LADBS, the city building department. A plumber can tell you whether your lowest fixture sits below the street manhole cover and handle the paperwork. Ask before you hire, and get the permit number on the invoice.
Can I clean up a small sewage backup myself?
Small spills on hard floors are sometimes handled by homeowners with gloves, boots and eye protection, but any carpet, pad, drywall or large area calls for a crew. Mops spread contamination and porous materials hold it. If you are unsure, stop and call.
Why do you remove carpet and drywall after sewage?
Porous materials absorb wastewater and cannot be disinfected from the surface. Crews remove what the water reached, mark the dry edge with moisture readings and clean and dry what remains. Removal is a scope decision based on readings, not a default.
Does homeowners insurance cover a sewer backup?
Often it is a separate coverage question. Check your policy for water backup coverage and ask your insurer or agent. Keep photos and receipts, and wait for your adjuster before discarding damaged belongings.
Can I get help with a sewage backup after midnight in West Hills?
Yes. The line is staffed all night and on holidays. Call (818) 337-2642, tell us which fixtures are backing up and whether anyone is standing in the water, and the scope and cost come before any work.