Sewage Backup

What does sewage backup mean?

A sewage backup occurs when wastewater flows in the wrong direction and enters a rental unit through a toilet, bathtub, shower, sink, floor drain, or another plumbing opening.

Possible causes include:

• A blocked or damaged building sewer line
• Collapsed, deteriorated, or improperly installed pipes
• Tree roots entering underground plumbing
• A municipal sewer problem
• A failing septic system
• Objects, grease, or other inappropriate materials placed into drains
• A plumbing problem affecting multiple units

Warning signs may include sewage odors, gurgling drains, several fixtures backing up at once, unusually slow drainage, wastewater entering tubs or showers, or contaminated water on floors.

A minor clogged drain is not necessarily a sewage backup or habitability violation. The source, severity, contamination, affected facilities, recurrence, and response after notice are all relevant.

Why does a sewage backup matter to tenants?

Sewage may contain harmful pathogens and other contaminants. Tenants should avoid direct contact, keep children and pets away from affected areas, stop using fixtures that worsen the backup, and immediately notify the landlord or emergency maintenance service.

The EPA advises avoiding contact with sewage and contacting the appropriate health or regulatory agency for guidance. Significant contamination may require professional removal, cleaning, disinfection, and drying.

Sewage can also damage flooring, drywall, furniture, clothing, and other belongings. If contaminated materials remain wet, the incident may lead to persistent odors, dampness, mold, or structural deterioration.

California Civil Code Section 1941.1 requires rental housing to have properly maintained plumbing and an approved sewage disposal system. A serious or recurring sewage backup may therefore raise habitability concerns.

Tenants should report the backup in writing as soon as possible. If it is safe to do so, they should photograph or record the affected area before cleanup and document which fixtures are unusable. Medical attention may be appropriate if someone has direct exposure or develops symptoms.

When should you speak to a lawyer?

A tenant may want to consult a lawyer when:

• Sewage remains in the unit after the landlord receives notice
• The same backup repeatedly returns
• The landlord clears a drain but does not repair the underlying problem
• Multiple apartments or common areas are affected
• Toilets, showers, or other essential plumbing cannot be used
• The contamination damages personal belongings
• The backup causes illness, injury, or displacement
• The landlord refuses professional cleanup of contaminated materials
• The landlord retaliates after the tenant reports the problem
• Code enforcement or a health department identifies violations

Responsibility depends on the cause. A landlord may be responsible when the backup results from deteriorated pipes, building-wide plumbing, poor maintenance, or failure to respond after notice. A tenant may be responsible when the blockage was caused by misuse or materials improperly placed into the plumbing system.

Useful evidence includes photographs, videos, written repair requests, plumber reports, inspection findings, cleanup records, medical documentation, damaged-property inventories, hotel receipts, and complaints from other residents.

Tenants should obtain legal advice before withholding rent, deducting cleanup costs, or ending the tenancy.

Related services and articles

• Slumlord Attorneys in California
• What Is Considered Unsanitary Living Conditions?
• How Long Does a Landlord Have to Fix Water Damage?
• What to Do When Your Landlord Will Not Make Repairs
• California Habitability Laws and Tenant Rights