Sewer Backup in Your Dearborn Basement: What to Do First, What to Throw Out

Is sewage in my basement dangerous?

Yes. Water that comes up a floor drain, toilet or basement sink is Category 3, meaning it can carry bacteria, viruses and parasites. It is a health hazard, not a cleaning job, and it should be kept away from skin, children, pets, food and anything you cannot throw away.

Restoration work sorts water into three categories, and sewage sits at the worst end. Category 1 is clean water from a supply line. Category 2 is gray water, such as a washing machine discharge. Category 3 is sewage, toilet backflow and rising floodwater from rivers and creeks. When water has come back up through a floor drain in a storm, it has travelled through the pipes of a sewer system and carries whatever is in them, so it is treated as Category 3 whether it looks murky or surprisingly clear.

That classification changes what the job is. A clean-water leak is a drying problem. Sewage is a contamination problem first and a drying problem second. The aim is to remove the contaminated material, clean and disinfect what can safely stay, and only then dry the structure. This is also why a quick mop-up with household cleaner does not make a sewage backup safe: it leaves the contamination in every porous surface it reached.

The standing water itself can also be an electrical hazard. If water is near outlets, a furnace, a water heater or an electrical panel, do not walk into it. Cut power only if you can reach the panel without stepping through water; if you cannot, leave it and ask the utility or an electrician for help. Anyone with a weakened immune system, open cuts, or breathing problems should be especially careful about being near the area at all.

What should I do in the first hour of a sewer backup?

Stay out of the water, keep children and pets away, stop using drains and toilets, photograph the damage from a safe distance, call your insurer, and call a restoration crew. Do not start cleanup yourself. Calling is the fastest fix, since phones here are answered 24/7 and a crew is dispatched as fast as one is available.

The first hour is mostly about not making things worse. The temptation is to start carrying wet items upstairs or to mop, and both spread contamination into rooms that were clean. The list below is the order that causes least harm.

Call (833) 490-5225 once you have done the safety steps. A crew is dispatched as fast as one is available, and the estimate is explained to you and approved by you before work starts. No arrival time can honestly be promised, particularly after a storm that has flooded many basements at once, which is another reason to make the call early and to keep yourself safe in the meantime.

• Keep people and pets out of the basement, and shut the door to the stairs if you can.
• Do not step into the water, and do not touch electrical equipment standing in or near it.
• Stop adding to the problem: no flushing, no showers, no washing machine or dishwasher until the drain is clear, because every gallon you send down goes to the same blocked or surcharged line.
• Take photographs and short video of the water line, the floor drain, damaged belongings and any visible marks on walls, before anything is moved.
• Open ground-floor windows for ventilation only if it is safe and the weather allows, and keep the upstairs separate from the basement air as far as possible.
• Tell your insurer promptly, and use the words sewer backup rather than only flood; your policy may treat them differently.
• Call for a crew. Crews wear protective gear, extract the water, and take moisture readings that document the loss.

Why do Dearborn basements back up when it rains hard?

Heavy rain can send more water into drains than the lines can carry, and the overflow finds the lowest opening, often a basement floor drain. Dearborn's flood information says its stormwater system was built for about three inches in 24 hours, and over 7.5 inches fell in about six hours on 25 to 26 June 2021.

The mechanism is simple even if the plumbing is not. Rain enters storm drains, downspouts and sometimes cracks and connections in older lines. When the volume exceeds what the pipes can carry, the system fills and the water level rises in the pipes. Anything connected to them at a lower elevation, such as a basement floor drain or a basement toilet, becomes the relief point, and water comes back up into the house.

The City of Dearborn's published flood information gives the local numbers. Its stormwater system was designed for roughly three inches of rain in 24 hours. The storm of 25 to 26 June 2021 brought over seven and a half inches, mostly in about six hours. That is not a small excess; as simple arithmetic, the design figure averages about an eighth of an inch an hour, while the storm averaged more than an inch an hour. The city also notes that east Dearborn sits at a lower ground elevation than west Dearborn and was developed before World War II, so its sewers were built to the standards of that time. Later infill removed several surface streams that once led to the Rouge River, leaving fewer places for water to go. The northeast and southeast ends took the worst and most widespread damage, though the whole city was affected.

What we are not going to do is tell you which kind of line serves your street. Whether a particular Dearborn street is on a combined line, a separate sanitary line, or something in between is not something the city's published information lets us say, and guessing would be unfair to you. The Dearborn Public Works office can tell you what serves your address. The wider regional picture, including Detroit's largely combined system and the August 2014 storm, is explained in our guide to combined sewer overflows and basement flooding in metro Detroit.

Older housing matters too. Full basements are the norm in pre-war and mid-century Wayne County homes, and the floor drain sits at the lowest point of the house, so it is the first place pressure shows. A finished basement in an east Dearborn house means the water meets carpet, trim and drywall almost as soon as it arrives.

What has to be thrown out after a sewer backup, and what can be cleaned?

Porous materials that sewage touched are discarded, including carpet, pad, insulation, low drywall, particleboard, mattresses and cardboard. Hard, non-porous surfaces such as sealed concrete, tile and metal can be cleaned and disinfected. Framing lumber is assessed case by case. Nobody can prove a porous material has been made clean, so removal is the safe answer.

This is the part homeowners find hardest, because the items look salvageable. The reason for discarding porous material is that sewage does not stay on the surface. It soaks into fibres, foam, paper and fine pores, where cleaning products cannot reliably reach and where testing cannot confirm that the contamination is gone. A material you cannot verify as clean should not stay in the house, particularly in a room where children play or where air from the basement reaches the living space.

The table gives the general pattern used in the trade. It is a rule of thumb, not a guarantee for your house: a technician inspects the actual materials, measures moisture, and decides item by item. Sentimental items such as photographs and documents are a special case; some can be professionally handled, and you should say so on the phone so they are set aside rather than discarded by default.

Taking things out is not the end of the job. After removal, the structure is cleaned, treated and then dried with air movers and dehumidifiers until moisture readings return to normal, which is the work described on the sewage backup cleanup page. Demolition without drying simply leaves a wet frame that will grow mold.

What should a homeowner never do after a sewage backup?

Never walk through the water, run a household wet vacuum on it, mix bleach with other cleaners, hang wet belongings in living areas, paint over stains, or use fans to push basement air around the house. Each step spreads contamination, creates fumes, or hides moisture that keeps feeding mold.

Most of the harm that follows a backup comes from well-meant action in the first day. A household wet vacuum is not built to handle sewage; it draws contaminated water and mist through a motor and exhausts it back into the room, and the tank and hose become contaminated themselves. Fans pointed at wet surfaces can drive contaminated moisture through the house. Mixing bleach with ammonia-based or acidic cleaners creates toxic gas, and sewage is not safely handled with a spray bottle anyway.

Painting over or sealing stained surfaces hides moisture and does not remove contamination. Moving wet carpet through the house tracks it across clean floors. Throwing everything into plastic bags and keeping them indoors invites odour and bacteria. Store the removed material outside only as the crew directs, because disposal of bulky wet material has its own rules and the crew will manage it.

There is one more thing not to do: delay the call because you are unsure whether the damage is covered. Water that sits worsens, and drying should start within a day or two, since EPA guidance is to dry water-damaged areas within 24 to 48 hours to limit mold. A moldy area under about 10 square feet can usually be cleaned by the homeowner, but larger areas, and any mold connected with sewage, need professionals. See the mold remediation page for how that is handled.

• Do not walk or wade in the water, or let children and pets do so.
• Do not use a household wet vacuum, shop vacuum or carpet cleaner on sewage.
• Do not flush, shower or run the washer while the drain is backing up.
• Do not mix cleaning products, especially bleach with anything else.
• Do not paint or seal over stains, or cover wet surfaces.
• Do not move wet material through clean rooms or keep it indoors in bags.
• Do not discard your insurance evidence: photograph first, then let the crew remove.

How does a backwater valve prevent sewer backup?

A backwater valve is a one-way valve fitted in the house sewer line that closes when sewage flows backward, so water surcharging in the main cannot enter your basement through the floor drain or toilet. It is installed by a licensed plumber, needs periodic checking, and does not stop groundwater seepage.

Of all the measures people talk about after a flood, the backwater valve is the one that directly addresses the way sewage gets in. It sits in the line that leaves the house. Normally, wastewater flows out through it freely. When the main sewer fills and pressure pushes water back toward the house, a flap or gate inside the valve closes, and the water cannot return into the basement drains. It is not magic: a sticky or debris-clogged flap does not close, and a valve that is never inspected may fail without anyone noticing until the next storm.

A valve also changes how the house behaves in a storm. While it is closed, anything you flush or send down a drain on the protected side cannot leave the house either, so toilets and sinks should be used sparingly when a surcharge is happening. A valve does not help with groundwater coming through the walls or floor, with window wells, or with a failed sump pump; those are separate pathways with separate fixes, and our guide to sump pump failure and a flooded basement covers the second.

Installing a valve is plumber's work and usually involves cutting into the floor or line, so a licensed plumber does it and the city's building department can tell you whether a permit applies. Dearborn Water Damage Restoration does not install valves or sump pumps; the crew's role is the cleanup and drying afterwards. Asking your own city's Public Works office whether any local help exists is worthwhile, but do not assume one does. The Detroit program that helps owners install valves is limited to Detroit addresses, as explained in our guide to the DWSD Basement Backup Protection Program, and a Dearborn address is not eligible for it.

Who pays, and what should I document?

Coverage is decided by your insurer under your own policy. Michigan's DIFS says sewer and water backup is not automatically covered, so ask whether you have a water-backup endorsement. Photograph before anything is moved, keep receipts, and ask the crew for moisture readings and photos you can share with your insurer.

A standard homeowners policy often covers sudden and accidental water damage such as a burst pipe, but usually does not cover surface flooding or sewer and drain backup unless a water-backup endorsement was added. DIFS, the state insurance regulator, advises discussing a backup option with an agent before a flood happens, and notes that federal flood insurance is a separate policy that typically takes 30 days to go into effect. It also advises against simply calling your damage a flood when reporting it, because a sewer back-up or failing sump pump may be covered under the policy.

None of that tells you how your claim will turn out, and we cannot. What you can do is make the file easy to read: a list of damaged items with photographs, dates and times, the crew's moisture readings, receipts for anything you pay for, and the name of the person you spoke to at your insurer. Our insurance guide for Michigan sewer backups goes through the process in more detail.