Sewage backups and drain overflows in Lake Stevens 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 Lake Stevens 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 — Lake Stevens Sewage ResponseThe four factors that make our Lake Stevens Sewage Cleanup service different from a general water damage company handling a sewage call.
COS Water Damage Restoration's Lake Stevens sewage cleanup crew operates under IICRC S520 standard — the industry's governing protocol for Category 3 contaminated water remediation. This covers the specific containment requirements, the PPE standards that protect our crew from pathogen exposure, the material removal requirements (what can be safely dried versus what must be removed and disposed of as a regulated waste stream), and the multi-application antimicrobial sanitization protocol that must be completed before any structural drying begins.
Proper disposal is a regulatory requirement, not a premium upgrade. It's standard on every Lake Stevens job.
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 Lake Stevens crew follows the sequence on every surface, every time.
Our Lake Stevens claim coordinators handle the insurance piece. We can coordinate clearance testing when it's required.
COS Water Damage Restoration handles the complete scope of Sewage Cleanup in Lake Stevens — from containment and extraction through material removal, sanitization, structural drying, and rebuild. Category 3 protocols, start to finish.
Containment is established before extraction begins. This is non-negotiable on every Lake Stevens sewage job.
No material gets dried in place unless it passes decontamination protocol first.
After material removal, every remaining structural surface — framing, subfloor sheathing, masonry, concrete, and any hard surface that contacted sewage water in your Lake Stevens 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 Lake Stevens team follows is designed to address the pathogen load that Category 3 water deposits on structural surfaces.
Odor neutralization is a final treatment step, not a product sprayed at the end to cover incomplete remediation.
Most WA homeowner's policies cover sewage backup events under a backup coverage rider. Our Lake Stevens claim coordinators are familiar with the specific documentation that backup claims require — including the distinction between backup events (covered) and sewer line failures (may require separate coverage) — and build your claim file from the first day to match what your carrier's adjuster will look for. We file the claim, coordinate the adjuster visit, and follow the settlement through. You focus on your household; we handle the insurance.
One company from sewage backup to finished reconstruction. No coordination gap, no separate contractor handoff.


Call +1-844-499-0972 and a live Lake Stevens 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.
No extraction, no material removal before the written scope is reviewed and approved by you.
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 Lake Stevens 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 Lake Stevens sewage cleanup right the first time. I'm telling every neighbor I know to call them first."
"Managing a rental property in Lake Stevens 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 Lake Stevens and surrounding communities throughout WA. 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 Lake Stevens Category 3 team responds fast, contains the event, and remediates to the standard that protects your household.
📞 Call +1-844-499-0972 — Lake Stevens Sewage Response24/7 Response · IICRC S520 Certified · Category 3 Protocols · Lake Stevens, WA