Sewage backups and drain overflows in Hathorne 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 Hathorne 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 — Hathorne Sewage ResponseThe four factors that make our Hathorne 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 Hathorne team is certified. The difference is measurable.
Proper disposal is a regulatory requirement, not a premium upgrade. It's standard on every Hathorne job.
One application of sanitizer after a sewage event is not sufficient. Our protocol uses multiple applications with documented dwell times.
Sewage cleanup claims in Hathorne typically proceed under homeowner's policy coverage for drain backup and water damage. Our Hathorne coordinators are experienced with backup coverage riders and know how to document Category 3 events for claim approval. For commercial properties or clients requiring clearance testing, we coordinate third-party air quality and surface sampling after remediation to provide a written clearance certificate before reconstruction begins.
COS Water Damage Restoration handles the complete scope of Sewage Cleanup in Hathorne — from containment and extraction through material removal, sanitization, structural drying, and rebuild. Category 3 protocols, start to finish.
The first action our Hathorne sewage crew takes on any Category 3 event is establishing negative-pressure containment — critical plastic sheeting barriers that prevent sewage contamination from spreading into unaffected areas of the property through airborne particles, foot traffic, and air circulation. Containment also controls odor migration within the property while remediation is underway. Simultaneously, we identify and coordinate the correction of the blockage or failure that caused the backup — whether that's a main line obstruction, a failed cleanout, or a sump failure — so that remediation isn't interrupted by a secondary event.
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 Hathorne 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 Hathorne 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 Hathorne 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.
Most MA homeowner's policies cover sewage backup events under a backup coverage rider. Our Hathorne 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.
After Category 3 remediation is confirmed complete by instrument readings and — where required — by third-party clearance testing, our licensed Hathorne reconstruction team rebuilds your property: new drywall, fresh insulation, flooring, paint, trim, and any affected cabinetry or millwork. All reconstruction is performed to the same documentation standard as the remediation phase, providing a complete recovery record from sewage event to finished property that your insurance carrier and any future property transaction will find clear and complete.


Sewage events require immediate evacuation of affected areas. Our dispatcher will confirm this on the call.
Our Hathorne crew arrives in full Category 3 PPE with containment materials, dedicated contaminated-water extraction equipment, and sanitization products. Containment is established before extraction begins — no exceptions. After containment, we identify the source of the backup and coordinate correction if needed before the cleanup scope is assessed.
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 Hathorne 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."
"The thing that stood out with COS Water Damage Restoration's Hathorne sewage cleanup team was the containment setup — I've seen other companies skip it or do it loosely, and you can tell they don't understand why it matters. This team had proper negative-pressure containment up before they extracted a gallon of water. The two-phase sanitization after material removal, the hydroxyl generator running during drying, the final surface swab coordination — this was a Category 3 remediation done to the actual standard, not a watered-down version of it."
"Managing a rental property in Hathorne 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 Hathorne and surrounding communities throughout MA. Call +1-844-499-0972 to confirm same-day service at your address.
Don't let an uncertified company handle a Category 3 sewage event in your Hathorne property. The health risk from incomplete remediation is real. Call +1-844-499-0972 — our certified Hathorne team handles it correctly.
📞 Call +1-844-499-0972 — Hathorne Sewage Response24/7 Response · IICRC S520 Certified · Category 3 Protocols · Hathorne, MA