Sewage backups and drain overflows in Posey are among the most hazardous water damage events a property can experience. Category 3 black water — raw sewage, backed-up drain lines, toilet overflows — carries bacteria, viruses, and pathogens at concentrations that make any contact a serious health risk. COS Water Damage Restoration's Posey sewage cleanup team is trained, equipped, and certified under IICRC S520 protocols for Category 3 biohazard remediation — from containment through full restoration.
📞 Call +1-844-499-0972 — Posey Sewage ResponseThe four factors that make our Posey Sewage Cleanup service different from a general water damage company handling a sewage call.
IICRC certification is the standard that defines whether a sewage cleanup was done correctly. Our Posey team is certified. The difference is measurable.
Sewage-contaminated materials removed from Posey properties — carpet, pad, drywall, insulation, and any porous material that absorbed Category 3 water — require regulated waste handling and disposal. Our Posey crew bags, labels, and disposes of all contaminated material to applicable CA regulatory requirements. No dumping in standard refuse. No leaving contaminated materials in dumpsters that aren't rated for biohazard waste.
After contaminated material is removed and Category 3 extraction is complete, every structural surface that contacted sewage water receives multiple applications of EPA-registered, hospital-grade antimicrobial and antifungal treatments. The sanitization sequence — spray application, dwell time, surface wipe-down, second application — is protocol-driven, not judgment-call driven. Our Posey crew follows the sequence on every surface, every time.
Our Posey claim coordinators handle the insurance piece. We can coordinate clearance testing when it's required.
Here's what our certified Posey Sewage Cleanup crew handles on every job.
Containment is established before extraction begins. This is non-negotiable on every Posey sewage job.
Extracting Category 3 sewage water from a Posey property requires specific PPE — full protective suits, respirators rated for biological hazard, and disposable boots — for every technician in the contamination zone. We use dedicated contaminated-water extraction equipment that is not shared with standard water damage jobs and is properly sanitized between uses. After extraction, all materials that contacted Category 3 water and cannot be decontaminated to a safe standard — carpet, pad, standard drywall, fiberglass insulation, and any non-cleanable surface materials — are removed as regulated waste, bagged in approved containers, and disposed of under CA biohazard material regulations.
After material removal, every remaining structural surface — framing, subfloor sheathing, masonry, concrete, and any hard surface that contacted sewage water in your Posey property — receives a multi-phase sanitization treatment using EPA-registered, hospital-grade antimicrobial and antifungal agents. The sanitization sequence includes spray application, documented dwell time, surface contact, and at minimum one additional application after the first dwell cycle. This is not a one-spray process. The S520 protocol our Posey team follows is designed to address the pathogen load that Category 3 water deposits on structural surfaces.
Category 3 sewage events leave odor-causing compounds embedded in structural materials, in the air space above the affected area, and — in HVAC systems — potentially distributed throughout the property. Our Posey team uses hydroxyl generator technology and botanical-based counteractant treatments to neutralize sewage odor compounds in the air and on surfaces, not mask them. For properties where HVAC ductwork may have been exposed to Category 3 contamination, duct isolation and decontamination is included in our scope evaluation.
Our Posey claim coordinators have processed Category 3 claims across CA carriers. We know what gets approved on first submission.
One company from sewage backup to finished reconstruction. No coordination gap, no separate contractor handoff.


Call +1-844-499-0972 and a live Posey dispatcher answers — not a recording. Describe the situation; our dispatcher confirms the sewage backup details, dispatches the nearest Category 3-equipped crew, and confirms estimated arrival. Evacuate the affected area and prevent household members and pets from entering while we're en route.
Containment before contact. Source identified and addressed before cleanup proceeds.
After initial containment and source control, our Posey project manager assesses the full Category 3 contamination extent, identifies all materials requiring removal, and prepares a written Xactimate-based scope covering extraction, material removal, sanitization, structural drying, and reconstruction. You review the scope and the cost before any material removal or treatment begins. If insurance is involved, the claim is filed the same day.
From sewage event to finished property — documented, guaranteed, and handled by one company.



"We have a young child and a dog and the moment the sewage smell hit I knew this was something I couldn't handle myself. COS Water Damage Restoration's Posey team was there in under 60 minutes, contained the area so our family could stay in the upper floors, and handled every part of the cleanup in a way I trusted. The clearance testing they coordinated at the end gave me documented proof that the remediation was complete."
"Three years later, no odor, no mold, no recurring issues. COS Water Damage Restoration did the Posey sewage cleanup right the first time. I'm telling every neighbor I know to call them first."
"Managing a rental property in Posey means sewage backups occasionally happen, and the response you choose matters enormously because you have tenant health and habitability on the line. COS Water Damage Restoration handled a Category 3 event at one of our properties with complete transparency — documented scope before work started, clear removal decisions explained in writing, and a clearance certificate at the end that we could show our tenant as proof the property was properly remediated. The insurance claim was settled without any dispute."
COS Water Damage Restoration's certified Category 3 sewage cleanup team serves Posey and surrounding communities throughout CA. Call +1-844-499-0972 to confirm same-day service at your address.
Sewage contamination requires certified remediation — not a general cleanup crew. Call +1-844-499-0972 and our Posey Category 3 team responds fast, contains the event, and remediates to the standard that protects your household.
📞 Call +1-844-499-0972 — Posey Sewage Response24/7 Response · IICRC S520 Certified · Category 3 Protocols · Posey, CA