What should I do in the first hour after water gets into my Naperville home?
Stay safe first, then stop the water, then protect what you can and take photos. Do not wait for the water to "settle" before you call for help, because the clock on drying starts the moment materials get wet.
- Check for electrical and gas hazards. If water is near outlets, cords or the electrical panel, do not walk into it. If you can reach your breaker panel from a dry spot, turn off power to the wet area. If you smell gas, leave the house and call for help from outside. The next section explains why.
- Stop the source if you can. For a burst pipe, a leaking water heater or an appliance hose, close the main water shutoff. It is usually where the water line enters the house, often next to the water meter. Find it now if you do not know where it is. For a sewer backup, stop running water, flushing toilets and using the washer or dishwasher, because every gallon you send down the drain can come back up.
- Take photos and video before you move anything. Get wide shots of each room, close-ups of the waterline on walls, the source if you can see it, and damaged belongings. Your insurer will ask for them.
- Move what you can to a dry place. Lift furniture off wet carpet, get electronics, papers and photos upstairs, and pull area rugs out of the water.
- Call your insurance company to open a claim if you think you will file one, and write down the claim number.
- Call a water damage restoration company. Ask how soon they can come out and what they will do on the first visit. If you call our line and press 1, we connect you with a local water damage restoration company.
If the water came up through a floor drain during heavy rain, there is one more step that is specific to Naperville: call the city before you call a plumber. The sewer backup section below explains why and gives the numbers.
Is it safe to walk into a flooded basement?
Not if the water touches outlets, plugged-in cords, the furnace or the electrical panel, or if you hear buzzing or crackling or see sparks. Shut power off from a dry location, or have an electrician do it, before anyone steps into standing water.
The CDC's guidance for flooded homes is blunt: never turn power on or off, and never use an electric tool or appliance, while standing in water. The Red Cross adds that you should stay out of any room where water covers plugged-in cords or outlets. If your electrical panel, furnace, water heater or laundry is in the basement, that is exactly where water collects.
- Power: If the panel is in the wet area, leave it alone. Naperville runs its own electric utility, and an electrician can also cut power safely. Before power goes back on, the CDC recommends having an electrician check the system.
- Gas: If you smell gas, the CDC says to turn off the main gas valve if you can do it safely, open windows and leave the house. Do not go back in until you are told it is safe.
- Dirty water: Treat any water that came from a floor drain, a toilet or outside as contaminated. Wear rubber boots and gloves, keep kids and pets out, and wash your hands well.
Where is the water coming from?
The source decides almost everything that follows: how dirty the water is, whether insurance is likely to help, and who you call first. Look for it before you start cleaning.
| What you see | Likely source | Usual water category | Read next |
|---|---|---|---|
| Water spraying or pooling near a pipe, often after a cold snap | Burst or split supply line | Category 1 at first | Burst or frozen pipes |
| Puddle around the water heater, washer, dishwasher or fridge | Appliance or its hose | Category 1 or 2 | Appliance and ceiling leaks |
| Stain or drip on a ceiling | Upstairs bathroom, appliance or roof | Category 1 or 2 | Appliance and ceiling leaks |
| Sump pit overflowing, pump not running | Failed or overwhelmed sump pump | Often Category 2 or 3 (groundwater carries soil) | Sump pump failure |
| Dark, smelly water rising from a floor drain or lowest toilet | Sanitary sewer backup | Category 3 | Sewer backup cleanup |
| Water seeping along the base of walls or through cracks after rain | Groundwater or surface runoff | Category 2 or 3 | Flooded basement |
What do Category 1, 2 and 3 water mean?
They are contamination levels from the IICRC S500, the industry's standard for professional water damage restoration. Category 1 is clean water, Category 2 is significantly contaminated "gray" water, and Category 3 is grossly contaminated "black" water such as sewage or rising floodwater.
You will hear these terms from the restoration company and often from your adjuster, so it helps to know them:
- Category 1 (clean): water from a sanitary source, such as a broken supply line or an overflowing sink. It does not pose a substantial risk on contact.
- Category 2 (gray): water with significant contamination that could make someone sick, such as washing machine or dishwasher discharge, or a toilet overflow with urine but no feces.
- Category 3 (black): grossly contaminated water that can carry pathogens, such as sewage, toilet backflow from beyond the trap, and floodwater from rivers or storm runoff that carries soil.
Two details matter for Naperville homeowners. First, water that backs up through a basement floor drain is sewage, so it is Category 3 even when it looks fairly clear. Second, clean water does not stay clean. Category 1 water can degrade into Category 2 or 3 as it sits, mixes with soil and building materials, and warms up. That is one more reason the first day matters.
The category changes the work. With Category 3 water, porous materials it touched, like carpet pad and the bottom of drywall, are usually removed rather than dried, and the area is cleaned and treated before drying. The EPA also advises that if water damage was caused by sewage or other contaminated water, you should bring in a professional who has experience with contaminated water.
What does the "class" of water damage mean?
Class describes how much water soaked into the room and how hard it will be to dry, from Class 1 (part of a room, little absorbed) to Class 4 (dense materials like hardwood, plaster or concrete that need specialty drying).
- Class 1: only part of a room is affected and materials absorbed little water.
- Class 2: a whole room of carpet and pad is wet and water has wicked up the walls, but less than about 24 inches.
- Class 3: the most absorbed water, often from overhead, with ceilings, walls, insulation and flooring saturated.
- Class 4: specialty drying for low-porosity materials like hardwood, plaster and concrete, which hold water deep inside and take longer.
A finished Naperville basement with carpet, pad and drywall that sat in water for a day is often Class 2 or 3. Knowing this helps you read the estimate: higher classes mean more drying equipment for longer.
What happens during professional water damage restoration?
A good company inspects and measures moisture, removes standing water, takes out materials that cannot be saved, dries the structure with air movers and dehumidifiers while tracking readings, cleans and treats contaminated areas, and then the damaged parts are rebuilt.
- Inspection and moisture mapping. The technician finds the source, decides the category and class, and uses moisture meters to see how far the water traveled, which is often farther than the visible stain.
- Water removal. Pumps and extraction tools pull out standing water and as much as possible from carpet and pad.
- Removing what cannot be saved. The EPA notes that porous materials such as ceiling tiles and carpet may have to be thrown away if they become moldy. After Category 3 water, wet carpet pad and the lower part of drywall are commonly cut out.
- Drying. Air movers and dehumidifiers run for several days. Ask the company to take and share moisture readings each visit so you can see progress and so your insurer has a record.
- Cleaning and treatment. Contaminated surfaces are cleaned, and after Category 2 or 3 water they are treated before rebuilding.
- Repairs. Drywall, insulation, trim, flooring and paint go back in. Some restoration companies do this themselves and some hand it to a contractor. Ask which up front.
"Mitigation" is the industry word for steps 1 to 5, the work that stops damage from spreading. "Restoration" or "rebuild" is step 6. Insurers often handle them as separate line items, so expect two estimates or one estimate in two parts.
How soon does mold start after water damage?
The EPA says water-damaged areas and items should be dried within 24 to 48 hours to prevent mold growth. Past that window, mold becomes much more likely, especially in a closed basement.
That timeline is the honest reason to call early rather than trying a shop vac and a box fan for a few days. Fans move air across the surface, but water that wicked into drywall, carpet pad and the bottom plate of a wall needs dehumidification and monitoring to come out.
If you already see mold, the EPA says an area smaller than about 10 square feet, roughly a 3 by 3 foot patch, is something most people can clean themselves. Larger areas, mold after sewage, or mold in the HVAC system are jobs for a professional. Our mold after water damage page covers this in more detail.
Who do I call first for a sewer backup in Naperville?
Call the City of Naperville before you call a plumber. The city's Water Utility will check whether the problem is in the city's main sewer line at no cost to you. The city lists (630) 420-6137 during the day and (630) 420-6060 after hours.
Naperville runs its own water and wastewater utility, and its sewer backup page asks residents to notify the city any time sewage backs up from a floor drain or from the sewer leaving the home, and says this is especially important during heavy rain. If the main is the problem, you save the cost of a plumber. If the main is clear, the city will tell you to hire a plumber for your private line and will measure the distance from your house to the main, which helps the plumber.
If only one fixture is backing up, such as a single toilet or sink, and every other drain works, the city says that is an internal problem and you should call a plumber directly.
Once the backup has stopped, the cleanup is a Category 3 job. That is where a water damage restoration company comes in. See sewer backup cleanup for what that involves.
After the cleanup, ask about the city's backflow program. Naperville reimburses 75 percent of the cost of an approved backflow prevention device for Water Utility customers whose sanitary sewer backed up because the system was surcharged by intense rainfall. You must call the Water Service Center to confirm the cause and get city approval before any work begins. The program does not cover stormwater flooding, water through foundation cracks or window wells, or a failed sump pump.
Why do Naperville basements take on water?
Heavy rain, clay-rich glacial soil, a river through the middle of town, and freezing winters. Add a housing stock where most homes are now 15 to 55 years old, with water heaters, sump pumps and hoses that wear out on their own schedule.
Big storms are part of local history
The July 17 to 18, 1996 storm dropped 16.94 inches of rain in 24 hours near Aurora, still the Illinois state record, and Naperville received about 14 inches. FEMA reported more than 35,000 residences flooded across the region. In April 2013, 4 to 8 inches of rain fell over the hardest-hit parts of northern Illinois, the East Branch DuPage River set a record crest at Bolingbrook, and in Naperville Centennial Beach flooded and had to be pumped out. Storms like these overwhelm sump pumps and surcharge sanitary sewers at the same time, which is why a single night can bring both groundwater and sewage into a basement.
The ground holds water
DuPage County sits on glacial deposits. The Illinois State Water Survey describes tills here that range from dense, clayey till to sandy, gravelly till, plus layers of silt and clay laid down in old glacial lakes. Clay drains slowly, so after a long rain the soil around a foundation stays saturated and pushes water toward any crack, joint or window well it can find.
The West Branch DuPage River runs through town
Naperville grew up on the West Branch DuPage River, and parts of the city drain to it. Homes near the river and its tributaries can see surface flooding that standard homeowners insurance does not cover. More on that in the insurance section.
Winters freeze pipes
The National Weather Service's 1991 to 2020 normal low for January in Chicago is about 19 degrees. Pipes in exterior walls, crawl spaces, garages and unheated rooms are at risk every winter, and a split pipe often is not noticed until it thaws. See burst or frozen pipes.
The housing stock is reaching its replacement years
According to the 2020 to 2024 American Community Survey as summarized by the Chicago Metropolitan Agency for Planning, the median Naperville home was built in 1990. About 40 percent of homes were built from 1970 to 1989 and another 41 percent from 1990 to 2009. Water heaters, sump pumps and supply hoses wear out with age, and a house built in the 1980s or 1990s may have gone through several of each. Those parts fail from age, not weather, and they fail on ordinary Tuesdays.
Does homeowners insurance cover water damage in Illinois?
It depends on where the water came from. Sudden, accidental water damage such as a burst pipe is generally covered. Flood from outside is not covered by a standard homeowners policy. Sewer and sump backups are usually covered only if you added a backup endorsement before the loss.
This is general information, not advice about your policy. Your declarations page and your agent have the final word. With that said, here is how coverage usually breaks down:
| Cause | Standard homeowners policy | What usually covers it |
|---|---|---|
| Burst pipe, appliance or water heater leak (sudden and accidental) | Generally yes | Your homeowners policy, minus the deductible |
| Slow leak or damage from poor maintenance | Generally no | Usually not covered |
| Sewer or drain backup, sump pump overflow | No, unless endorsed | A sewer and drain backup endorsement added before the loss |
| Flood (surface water, river overflow) | No | A separate flood policy, such as one through the NFIP |
The Illinois Department of Insurance states plainly that standard homeowners policies do not cover flood damage. The Insurance Information Institute notes that sewer backups are not covered by a typical homeowners policy or by flood insurance, and need their own endorsement. Backup endorsements carry their own limit, often far below the cost of finishing a basement, so check the number. And if you are thinking about flood coverage for next time, FEMA says an NFIP policy typically has a 30-day waiting period before it takes effect.
Practical steps that help any claim: photograph everything before cleanup, keep damaged items until the adjuster says you can discard them (or photograph them with a tape measure for scale), save receipts for anything you buy, and ask the restoration company for moisture readings and a written scope. Our guide on insurance and water damage in Illinois goes further.
How much does water damage restoration cost?
Nationally, HomeAdvisor puts the typical water damage restoration job at about $1,383 to $6,369, with an average near $3,868 and a full range from about $450 to $16,000. These are national figures, not Naperville quotes. Your price depends on the water category, square footage, how long it sat and what must be rebuilt.
HomeAdvisor's June 2026 figures also give a sense of how contamination changes the price for the drying and cleanup work: about $3.50 per square foot for clean water, $5.25 for gray water and $7.50 for black water. Mold removal, when needed, is listed at roughly $1,100 to $3,400.
What pushes a bill up: Category 3 water, a finished basement with carpet and drywall, water that sat for more than a day or two, and anything that has to be rebuilt. What keeps it down: stopping the water early, moving belongings out quickly and starting the drying within the EPA's 24 to 48 hour window. Our cost guide explains how to read an estimate line by line.
Do I need a permit to rebuild after water damage in Naperville?
Drying and cleanup do not usually need a permit, but rebuilding often does. The City of Naperville requires permits for remodeling, including basements, while cosmetic work such as painting, wallpapering, carpeting and trim does not.
The city's Guide to Building Permits lists basement remodeling among projects that need a permit, and the city's own permit records show permits issued for interior restoration after weather damage, including drywall, insulation and flooring. A like-for-like water heater replacement does not need a permit under the guide, while a new or different water heater does. Ask the company or contractor doing the rebuild who pulls the permit, and get it in writing. If you live in a neighboring town, check with that village or city, since rules differ.
How do I choose a water damage restoration company?
Ask direct questions before anyone starts: what they will do on the first visit, how they measure drying, whether their technicians are trained to the IICRC S500 standard, how they work with insurers, and whether they will put the scope and price in writing.
- "How soon can you come out, and what happens on the first visit?" You want extraction and drying set up, not just an estimate.
- "Will you take moisture readings each visit and share them?" Drying logs protect you and your claim.
- "Are your technicians trained in water damage restoration?" The IICRC offers water damage training tied to the S500 standard. Ask, and ask to see proof.
- "Can I see your license and insurance?" Always ask before work starts.
- "Do you bill my insurance directly, and what will I owe?" Understand the deductible and anything your policy may not cover.
- "Who does the rebuild, and who pulls the permit?"
- "Can I have a written estimate before work starts?"
Be cautious with anyone who pressures you to sign over insurance benefits on the spot without explaining what that means, or who will not leave paperwork. A stressful day is exactly when slowing down for five minutes pays off.
What does this site do, and what happens when I call?
We are a free referral service, not a restoration contractor. When you call and press 1, we connect you with a local water damage restoration company that serves your area. That company does the work and sets its own prices.
There is no charge to you for the call or the connection. The company you speak with will ask about the source, how much water there is and how long it has been there. Ask them the questions above. If they are not a fit, you are free to hang up and call someone else. You can read more on our how it works page.
Water damage help by problem
Nearby towns
We also connect homeowners in the towns around Naperville: Aurora, Plainfield, Bolingbrook, Lisle, Wheaton and Warrenville. Each page covers who to call for sewer problems in that town.