Heavy rain can overload the sewer system, and sewage can then rise through a basement floor drain. Columbus runs Project Dry Basement, which installs an approved backflow prevention device on eligible homes, but the device only blocks sanitary sewer backup through a basement drain. A backup must be reported to the city within 24 hours so the city can determine whether rainwater caused it.
Key takeaways
- Heavy rain can overload Columbus sewers and push sewage up through a basement floor drain, which is why the city has worked under two Ohio EPA consent decrees since 2002 and 2004.
- Project Dry Basement pays for an approved backflow prevention device on eligible single- and two-family homes, including rentals, and the city's certified plumbing contractor does the installation.
- The backflow device stops sanitary sewer backup through a basement drain only, so it does nothing about water seeping through walls, windows or the slab.
- A sewer backup must be reported to the city within 24 hours of the incident so the city can determine whether rainwater caused it.
- Sewage is Category 3 water under IICRC S500, so children and pets stay out until the area has been cleaned and dried.
- A standard homeowners policy generally excludes sewer and drain backup unless an endorsement or rider is added, so check your policy and call your insurer early.
Why do Columbus basements back up when it rains hard?
When a storm delivers more water than the sewers can carry, sewage can rise through the lowest drain in the house, usually the basement floor drain. Large rain events on the Scioto, Olentangy and the east-side creeks make that load more likely.
Columbus sits where the Scioto and Olentangy rivers meet, and Alum Creek, Big Walnut Creek and Blacklick Creek run down the east side. The Columbus Stormwater Drainage Manual names those five streams as the main ones in and around the city. A basement floor drain sits at the low point of the house, so when the system backs up, that is often where the first sign appears. The water comes up from below, not down from the roof, which is why a dry basement can turn wet in an hour.
The National Weather Service measured 4 to 7 inches of rain in the heaviest areas of Franklin and Licking counties on 19 and 20 August 2026, with significant overland and river flooding and numerous road closures. Rain of that kind is the kind that tests the sewers. Wall seepage is a separate problem, and it runs highest in the wet months, because the high water table in Pewamo soils sits near the surface from December to May.
Why is sewer backup such a big issue in Columbus?
The city entered two consent decrees with Ohio EPA, in 2002 and 2004, to eliminate sewage backups into homes and overflows into the rivers during wet weather. That commitment shapes how the city spends on sewers and basements.
The city's answer is Blueprint Columbus, which has four pillars: sewer lining, roof drain redirection, sump pump installations and green infrastructure. Each one targets a different route by which rainwater reaches the sanitary sewer or a basement. The Division of Sewerage and Drainage runs that work, and a homeowner's basement is one of the places where the results show up. Knowing the program helps a reader understand why the city asks about basement water in its own questionnaire.
Older houses add a second layer of risk. Clay sewer laterals can crack where street-tree roots reach them, and original cast-iron waste stacks in pre-war homes can rust through. Water from a street-side problem and water from a failing line inside the house can look the same once it is on the floor. A plumber is needed to tell them apart and to repair whatever failed. The older Columbus home plumbing guide covers those materials in more detail.
What does Project Dry Basement actually cover?
Project Dry Basement is a City of Columbus program that pays for an approved backflow prevention device on eligible single- and two-family homes, including rentals. It has run since 2004, and 1,814 devices had been installed as of the 2024 Public Utilities annual report.
The device is installed by the city's certified plumbing contractor, not by the restoration crew that cleans up after a backup. Its job is narrow: it prevents sanitary sewer backups from coming up through a basement drain. Eligibility is decided by the city, so ask the City of Columbus whether a particular home qualifies rather than assuming it does. A reader should not treat the program as a general basement flood fix.
What the device does not do matters just as much. It does nothing about seepage through basement walls, windows or the floor, and water that enters that way needs a different fix. If a basement floods in a storm and the water is clearly coming through the walls, a valve will not stop it. The basement flooding and sump pump guide explains those other routes. The city's program page on columbus.gov sets out the eligibility and the process.
What is the 24-hour reporting rule?
A sewer backup has to be reported to the city within 24 hours of the incident so the city can determine whether rainwater caused it. The report is tied to eligibility under the program, so it is the step most worth doing early.
Call the city's 24-hour Sewer Maintenance Operations Center at 614-645-7102, or dial 311. You can also complete the online Wet Basement and Neighborhood Flooding Questionnaire on columbus.gov. Before you call, write down when you first saw water, what it looked like, and whether it rained heavily that day. Those details make the report easier to act on and give the city a clear timeline.
Take photos before anything is moved, and keep the affected area as it was for as long as it is safe to do so. If you also call your insurer, tell them you reported the backup to the city. A report to the city does not replace an insurance claim or a repair, and it does not decide who pays for either. Keep copies of everything you send so you can show the timeline later.
What should you do in the first hour after a backup?
Keep people and pets out of the water, stop using drains and toilets in the house, and stay away from the electrical panel and any outlet near standing water. Sewage is contaminated water, so treat the basement as off limits until it has been cleaned and dried.
Do not wade into wet areas near the furnace, the water heater or the electrical panel. Shut off power to the basement only if you can do it without standing in water. If the backup is coming up through a floor drain, avoid running water into the house while it continues, since more water can push the sewage further. Once the house is safe, call a plumber to clear or repair the line.
Then call a restoration crew. Phones are answered 24/7 and a crew is dispatched as fast as one is available, though nobody can promise a specific arrival time. Sewage is Category 3 water under IICRC S500, the most involved class of water, and EPA guidance is to dry water-damaged areas within 24 to 48 hours to limit mold. The sewage backup cleanup service covers that work in detail.
What does the crew do once it arrives?
The crew removes standing water, checks for hidden moisture with moisture meters and thermal imaging, and sets air movers and dehumidifiers. It re-checks readings until the materials are dry, and it can provide photos and moisture readings for your claim.
The emergency stage, covering extraction and drying setup, is explained and approved before work starts, and the price is confirmed on site before any work begins. Repairs after drying are quoted separately, once someone has seen the wet area, because nobody can price the rebuild honestly over the phone. Materials that cannot be dried, such as saturated carpet pad, some drywall and sometimes subfloor, are often removed, and the crew should explain which ones and why. The water damage restoration page describes the full sequence.
Mold is a reason to move quickly, not a reason to panic. Mold can trigger allergy and asthma symptoms in some people. Ohio does not license mold remediation the way some states do, so ask any company which standard it works to. The IICRC is a non-government industry body that publishes ANSI/IICRC S500 for water damage and S520 for mold, and it certifies individual technicians. You can ask a technician which certifications they hold.
Does homeowners insurance pay for a sewer backup?
Usually not by default. A standard homeowners policy generally responds to sudden and accidental water damage, but generally excludes sewer and drain backup, which is covered only through an added endorsement or rider.
The Ohio Department of Insurance lists water damage from a sewer backup or basement leak among the typical exclusions on HO-2 through HO-6 forms. The answer therefore depends on your policy and on any endorsement attached to it. Check your declarations page, or ask your agent whether a sewer backup endorsement is included. Flood is a different matter. Surface water from rivers and creeks is handled through a separate flood policy, either through FEMA's National Flood Insurance Program or a private insurer.
Coverage is decided by your insurer under your own policy, not by the crew. The crew can document the damage and provide moisture readings and photos for your claim. If you have a dispute over how a claim was handled, the Ohio Department of Insurance takes consumer complaints. It reviews whether the insurer followed the policy and state insurance law, but it does not decide how much damage is worth.
Who repairs the pipe, and who pulls the permit?
A licensed plumber repairs the sewer lateral, the floor drain or the waste stack. In Columbus the plumber must also be registered with the city, and a registered contractor pulls the trade permit after the building permit is issued.
Plumbing work is licensed in Ohio. The state board licenses commercial plumbing contractors, and city building departments handle residential registration. Readers can ask any company which license it holds and check it with the issuing office. Columbus contractor registration falls under Columbus City Code Chapter 4114, and a bond is required. Check the current schedule with Building and Zoning Services rather than relying on an older figure.
A homeowner may pull a plumbing permit only for work they do themselves on a single-family home they live in. A homeowner may not buy a permit for work a contractor will do. Building and Zoning Services can be reached at 614-645-7433, and plumbing inspections at 614-645-8355. Outside Franklin County, the permit office is the county or city where the house sits, not the City of Columbus.
Frequently asked questions
Will Project Dry Basement stop my basement from flooding?
It stops one route only: sanitary sewer backup through a basement drain. The program installs an approved backflow prevention device on eligible homes, and the city's certified plumbing contractor does the work. It does not stop seepage through walls, windows or the floor, so water coming in from outside is a different problem. Ask the City of Columbus about eligibility before assuming a home qualifies.
How long do I have to report a sewer backup to the city?
Report within 24 hours of the backup. The city uses the report to determine whether rainwater caused it, and that determination is tied to the program. You can call the 24-hour Sewer Maintenance Operations Center at 614-645-7102 or dial 311. The online Wet Basement and Neighborhood Flooding Questionnaire is also available on columbus.gov.
Is sewage in a basement dangerous?
Sewage is Category 3 water, the most contaminated class. Keep children and pets out of the area, and do not touch the water without protection. EPA guidance is to dry the area within 24 to 48 hours, because fast drying helps limit mold. Mold can trigger allergy and asthma symptoms in some people, so tell the crew if anyone in the house has those conditions.
Can the restoration crew fix the sewer line?
No. Repairing a pipe, a sewer lateral, a water heater or a waste stack needs a licensed plumber, and in Columbus that plumber must be registered with the city. The crew handles the standing water, the drying and the cleanup. Ask the crew to explain what it can and cannot do before work starts.
Will my insurance pay for the cleanup?
It depends on your policy. Standard homeowners policies generally exclude sewer and drain backup unless an endorsement or rider is added. Read your policy, ask your agent, and call your insurer early. The crew can document the damage and provide moisture readings and photos, but coverage is decided by your insurer.
How do I get a crew out after a backup?
Call (833) 490-5225. Phones are answered 24/7 and a crew is dispatched as fast as one is available, though no arrival time can be promised. Have the address, the type of water you are seeing, and whether anyone is in the house ready. Those details help the crew plan the trip and the first steps.
Sources
- City of Columbus Department of Public Utilities
- City of Columbus Department of Public Utilities, Project Dry Basement
- National Weather Service Wilmington
This guide is general information for Franklin County homeowners, not a substitute for an on-site inspection. Prices are estimates. See our disclaimer.