Overhead Sewer Conversion in Chicago: A Lasting Fix for Sewer Backups
If you’ve ever watched sewage rise from a basement floor drain after a heavy storm, you know a mop and a wet vac aren’t a solution. Overhead sewer conversion in Chicago is one of the few plumbing upgrades that removes the cause of the problem and doesn’t just manage the symptoms. We design and install overhead sewers for Chicago homeowners who are tired of cleaning up after every big rain.
This page explains how an overhead sewer works, how it compares with other options, what the process looks like, and where to check on basement flooding rebates before you commit to a project.
Why Chicago basements flood in heavy rain
Much of Chicago is served by a combined sewer system, which means storm water and household wastewater travel through the same underground pipes. In a normal week that works fine. In intense rain the system can fill faster than it drains, and the water level in the street sewer rises above the level of your basement plumbing.
When that happens, the pressure pushes wastewater backward through your sewer lateral and up through the lowest openings in your home: floor drains, basement toilets, laundry sinks and utility tubs. Plumbers call this a sewer surcharge.
Homes that are most exposed
Homes with finished basements, in-law apartments, basement laundry rooms or bathrooms below grade carry the most risk, because more is at stake when water arrives. Bungalows, two-flats, greystones and older brick homes in neighborhoods like Portage Park, Irving Park, Albany Park, Bridgeport and Beverly often have basement fixtures connected to the street sewer at a low elevation.
Sewer backup isn't the same as seepage
Water seeping through walls or cracks is a drainage and waterproofing issue. Sewer backup is a plumbing issue, and the water is contaminated. It needs a plumbing solution.
What an overhead sewer conversion is
An overhead sewer conversion changes how your basement drains reach the city sewer. Instead of flowing down by gravity into the main line, wastewater from basement fixtures collects in a sealed pit. An ejector pump then lifts it to a drain line positioned above the level a street sewer surcharge can reach.
Because the basement drains no longer connect directly to the lower sewer path, backed-up water has no way into your living space. The protection comes from the design of the plumbing itself, and not from a part that has to close at the right moment.
The main parts
- A sealed, vented ejector basin that collects wastewater from basement fixtures
- An ejector pump sized for your fixtures and household use
- A check valve on the discharge line to keep water from flowing back into the basin
- An overhead discharge line that ties into your building drain above the surcharge level
- A battery backup (strongly recommended), so the system keeps working through storm-related power loss
What a conversion looks like in practice
After an on-site inspection, we plan where the pit will go, cut and remove sections of the basement floor, connect your basement fixtures to the new system, and reroute the discharge. The floor is then restored. We handle the permit paperwork and the final inspection as part of the job.
Backflow valve or overhead sewer?
Homeowners often ask whether a backflow valve is enough. The honest answer is that it depends on your home, your risk, and how you use your basement.
How a backflow valve works
A backflow valve (also called a backwater valve) is installed on your sewer line and closes when water tries to flow backward. It costs less than an overhead sewer and works well in the right conditions.
Where a backflow valve falls short
It has moving parts that need regular inspection and cleaning, and debris can stop it from sealing fully. While it’s closed, basement fixtures generally can’t be used without risking sewage getting trapped in your own pipes. And it depends on the valve closing correctly, at the right time, in every storm.
Where an overhead sewer stands out
An overhead sewer keeps basement fixtures usable during a surcharge and doesn’t depend on a valve sealing in time. For finished basements, basement bathrooms and homes that have already flooded more than once, many owners find the extra protection worth the higher upfront cost. In some homes we also recommend a backflow valve as an added layer. We’ll tell you plainly which option fits your property, even if that means the simpler one.
Building a complete flood control plan
Sewer backup is only one way water gets into a basement, so the best protection looks at the whole picture. A good plan can combine several measures, each handling a different risk:
- An overhead sewer or backflow valve to block sewer backup
- A sump pump with battery backup to manage groundwater
- A review of downspouts and grading to move roof and yard runoff away from the foundation
- An inspection of window wells and drains to close off smaller entry points
We don’t sell add-ons your home doesn’t need. During the assessment we work out how water is really getting in and recommend only what addresses it. That avoids the common trap of paying for a fix that doesn’t match the problem.
Basement flooding rebates: what to know first
Homeowners often ask about a Chicago basement flooding rebate. Programs have existed through the City of Chicago’s Basement Flooding Partnership and some nearby suburbs, but eligibility rules, funding and amounts change over time. Before you sign anything:
Check what's available
Call 311 or contact the City of Chicago Department of Water Management to ask which flood control or sewer backup programs are open for your address.
Ask about timing
Some programs require approval or a pre-inspection before work begins, so don’t start the project first and apply later.
Keep your paperwork
Save your permit, invoice and inspection records. Program administrators often ask for them.
We’re happy to provide the documentation your application may need. We can’t guarantee that any particular rebate will be approved, and we’d rather you hear that now than after the work is done.
Permits, codes and doing it right
An overhead sewer conversion changes your home’s drainage, so it’s regulated work. In Chicago, this kind of project is done under a plumbing permit and inspected by the city. We handle the permit, scheduling and inspection coordination, so you aren’t left chasing paperwork.
Skipping permits can cause problems later, from failed inspections to complications when you sell. Doing it correctly the first time protects both your basement and your property record.
How the process works with us
On-site assessment
We inspect your basement plumbing, review how your home connects to the sewer, and talk through your flooding history. If needed, we recommend a camera inspection of the sewer lateral to check for roots, breaks or blockages that could add to the problem.
A written scope and quote
You get a clear written scope of work with the equipment specified, so you know what you’re paying for.
Permit and installation
We pull the permit, complete the conversion, test the system and restore the work area.
Inspection and walkthrough
After the city inspection, we walk you through the system, show you the pump test, and explain the simple maintenance so you know how it all works.
Serving Chicago homeowners
We work with homeowners across Chicago and nearby suburbs. Every home has a different layout and sewer connection, which is why we start with an inspection and not a one-size-fits-all package. See the neighborhoods on our service areas page.
Already dealing with a slow drain or recurring clogs? Our drain rodding service can clear the line and help us see whether it’s adding to your backup problem.
Get a straight answer about your basement
You shouldn’t have to guess whether your home needs an overhead sewer, a backflow valve, or something simpler. We’ll inspect your plumbing, explain your options in plain language, and give you a written quote with no pressure. Request a visit or call (773) 588-1200.
Overhead sewer conversion questions
It's a plumbing upgrade that reroutes basement drains into a sealed pit and pumps the wastewater up to a line above the sewer surcharge level. That keeps street sewer backups out of your basement fixtures, even in heavy rain.
Basement fixtures drain into a sealed, vented ejector basin. A pump lifts the wastewater to an overhead line, which then flows by gravity into the sewer. A check valve stops water from returning, so a rising sewer level can't push wastewater back into the basement.
For many homes it gives stronger protection, because it doesn't depend on a valve closing at the right moment and it keeps basement fixtures usable. A backflow valve costs less and suits some properties. An assessment shows which fits your home.
Rebate and assistance programs have been offered through the City of Chicago and some nearby municipalities, but availability and amounts change. Call 311 or the Department of Water Management to confirm what's open for your address before starting any work.
The cost depends on basement layout, floor material, number of fixtures, pipe condition and access. Because those details vary so much from home to home, a written quote after an on-site inspection is the only reliable way to know your price.
Yes. This work changes your drainage system, so it's done under a plumbing permit and city inspection. We pull the permit and schedule the inspection for you.
Most projects take a few days, depending on the size of the job, floor conditions and inspection scheduling. You'll get a timeline in the written scope after we inspect your basement.
The ejector pump needs electricity, so a battery backup is strongly recommended. With a properly sized backup, the system can keep running through storm-related outages, which is when backup risk is highest.
It stops flooding caused by sewer backup, which is one major cause. It doesn't address groundwater seepage, foundation cracks, window wells or surface runoff. A full flood control plan covers each of those separately.