A sewage backup is one of the most alarming and hazardous situations a homeowner can face. Unlike a burst pipe or a roof leak, sewage backup introduces Category 3 contamination — the highest risk classification in water damage — directly into your living space. The water is not just dirty; it contains bacteria, viruses, and pathogens including E. coli, Salmonella, Hepatitis A, and Norovirus. Exposure can cause serious illness, and the contamination spreads rapidly to porous materials like drywall, flooring, insulation, and soft goods.

If you are dealing with a sewage backup right now, this guide tells you exactly what to do — and what not to do — to protect your family and your property.

Step 1: Get Everyone Out of the Affected Area Immediately

Do not walk through sewage water. Do not attempt to clean it up yourself. Do not let children or pets into the affected area. Category 3 water is a health hazard, and even brief skin contact can cause infection. If the backup is significant and has spread to multiple rooms, consider evacuating the home entirely until professional remediation is complete.

If you must enter the area — for example, to shut off water or retrieve essential items — wear rubber boots, waterproof gloves, and eye protection at minimum. Wash your hands and any exposed skin thoroughly with soap and water immediately after leaving the area.

Step 2: Stop Using Water in the Home

If your sewer line is backed up, every drain in the house connects to the same blocked system. Running water anywhere — flushing toilets, running sinks, using the dishwasher or washing machine — will add more water to the backup and make the situation significantly worse. Stop all water use in the home immediately and instruct everyone in the household to do the same.

Do not attempt to plunge a toilet or drain that is backed up. Plunging can force contaminated water further into the system and may cause it to overflow from other fixtures.

Step 3: Identify the Source

Sewage backups typically have one of three causes, and identifying which one you are dealing with affects both the urgency and the solution.

Main sewer line blockage is the most common cause. Tree roots, grease buildup, collapsed pipe sections, or debris accumulation in the municipal sewer line or your home's main lateral can block the entire system. When the main line is blocked, sewage backs up through the lowest drain in the house — typically a floor drain in the basement or a ground-floor toilet.

Municipal sewer system overflow occurs when the public sewer system is overwhelmed, usually during heavy rain events. Stormwater infiltrates the sewer system and causes sewage to back up into homes connected to it. This is more common in older neighborhoods with combined storm and sanitary sewer systems.

Individual drain blockage affects only one fixture and is typically caused by a localized clog. If only one toilet or one sink is backing up while others drain normally, the blockage is likely in the branch line serving that fixture rather than the main line.

Call a licensed plumber to diagnose and clear the blockage. Do not call a drain cleaning service and then assume the problem is solved — clearing the blockage stops the backup from getting worse, but it does not address the contamination that has already occurred.

Step 4: Document Everything Before Cleanup Begins

Before any cleanup or remediation work begins, document the full extent of the damage with photos and video. Walk through every affected area and capture:

• The extent of sewage water spread, including water level marks on walls
• All affected materials — flooring, baseboards, drywall, cabinets, furniture, personal belongings
• Any visible source or point of entry (the overflowing toilet, the floor drain, the cleanout)
• The date and time you discovered the backup

This documentation is essential for your insurance claim. Do not discard any damaged materials until your insurance adjuster has assessed the damage.

Step 5: Call Your Insurance Company

Whether sewage backup is covered by your homeowner's insurance depends on your specific policy. Standard homeowner's policies typically cover sudden and accidental water damage from internal sources — such as a burst pipe — but may exclude or limit coverage for sewer backup. Many insurers offer sewer backup coverage as an endorsement (add-on) to the standard policy for a modest additional premium.

Call your insurance company immediately to report the loss and ask specifically about your sewer backup coverage. Request a claim number and ask about the timeline for adjuster inspection. Also ask whether your policy covers temporary housing if the home is uninhabitable during remediation.

Even if your policy does not cover sewer backup, document the damage thoroughly. If the backup was caused by a municipal sewer system failure, you may have a claim against the city or municipality.

Step 6: Call a Professional Biohazard Remediation Company

This is not a situation you can address with a mop and bleach. Category 3 contamination requires professional remediation for several reasons:

Bleach does not work on porous materials. Bleach can disinfect hard, non-porous surfaces, but it cannot penetrate drywall, wood framing, insulation, or flooring to kill pathogens embedded in those materials. The only safe approach is to remove all porous materials that came into contact with sewage water.

The contamination is invisible. Sewage water wicks into wall cavities, under flooring, and into insulation through capillary action. Even after the visible water is removed, contamination persists in materials that appear dry. Professional technicians use moisture meters and thermal imaging cameras to locate hidden contamination.

Improper cleanup spreads contamination. Attempting to clean up sewage without proper containment, PPE, and negative air pressure can spread pathogens to unaffected areas of the home through foot traffic, HVAC systems, and air movement.

At Texas Restoration Group, our biohazard remediation process begins with full containment and negative air pressure setup to prevent cross-contamination, followed by removal of all affected porous materials, EPA-registered hospital-grade disinfection of structural surfaces, HEPA air scrubbing, and thermal fogging to neutralize odors. We document every step for your insurance file and coordinate directly with your adjuster throughout the process.

Step 7: Address the Odor

Sewage odor is one of the most persistent consequences of a backup event. The odor compounds — hydrogen sulfide, methane, ammonia, and various volatile organic compounds — embed into porous materials at a molecular level. Standard cleaning and air fresheners cannot eliminate them.

Professional odor remediation following a sewage backup involves thermal fogging with specialized deodorizing agents that penetrate the same porous surfaces the odor compounds have reached, HEPA air scrubbing with activated carbon filters to capture airborne VOCs, and antimicrobial treatment of all affected surfaces. In severe cases, HVAC ductwork may need to be cleaned and treated as well, since the air handling system can distribute odor compounds throughout the home.

What Not to Do

Several common instincts in a sewage backup situation will make things worse:

• **Do not use bleach as your primary disinfectant.** It is not effective on porous materials and creates a false sense of security.
• **Do not run fans to dry the area.** Fans spread contaminated air and can push pathogens into unaffected areas.
• **Do not discard damaged materials before documentation and adjuster inspection.** Throwing things away before the claim is assessed can reduce your settlement.
• **Do not delay calling a professional.** Category 3 contamination does not become safer with time — it becomes more deeply embedded and more expensive to remediate.

When to Call Texas Restoration Group

If you are dealing with a sewage backup anywhere in the Austin metro area or surrounding Central Texas communities, call (512) 883-7364 immediately. Our IICRC-certified biohazard remediation team is available 24 hours a day, 7 days a week, and can typically be on-site within 59 minutes. We handle the complete remediation process from containment through clearance, and we work directly with all major insurance carriers to support your claim from day one.