Last updated Reviewed by our licensed Chicago master plumber team
Many Chicago homes have a plumbing fixture below the level of the main sewer line — a basement bathroom, a laundry room, a wet bar, or a slop sink. Gravity alone can't get wastewater from those fixtures up and out to the sewer, so an ejector pump (sometimes called a basement sewage pump or sewage ejector) does the lifting. Unlike a sump pump — which handles clean groundwater — an ejector pump handles actual sewage including solids, so it requires sealed pit, gas-tight lid, dedicated vent, and a pump rated to handle 2" solids. Plumbers 911 Chicago services, repairs, replaces, and installs ejector pumps across Chicago and 245 surrounding cities. We handle full new-system installations for basement bathroom remodels ($3,200 – $6,800), straight pump replacements in existing pits ($725 – $2,400 depending on horsepower), and 24/7 emergency response when a failed pump is flooding a basement. Every installation uses quality brands (Zoeller, Liberty, Hydromatic, Myers), cast-iron impeller pumps (plastic impellers fail faster), sealed gas-tight lid, dedicated 2" vent to roof, and a check valve on the discharge. We also recommend sump pump battery backup as a universal add-on since a power failure can flood your basement with sewage in under an hour. Call 833-758-6911 for service. Related: sump pump installation, bathroom remodeling, sewage backup cleanup, emergency plumber, and plumbing inspection.
Ejector Pump vs. Sump Pump: Critical Difference
People mix these up constantly. They do completely different jobs and are NOT interchangeable.
| Feature | Ejector Pump | Sump Pump |
|---|---|---|
| Handles | Sewage + wastewater + solids | Clean groundwater only |
| Pit type | Sealed, gas-tight | Open or vented |
| Lid | Gas-tight with cable pass-throughs | Usually open or lightly covered |
| Venting | Required — dedicated 2" vent to roof | Not required |
| Solids handling | 2" solids rated minimum | No solids (fails if solids enter) |
| Impeller | Heavy cast iron or vortex design | Light plastic or steel |
| Typical HP | 1/2 – 1 HP | 1/3 – 1/2 HP |
| Typical cost | $725 – $2,400 replacement | $450 – $1,400 replacement |
| Purpose | Lifts wastewater from below-grade fixtures | Prevents groundwater basement flooding |
What Uses an Ejector Pump
- Basement half-bath (toilet + sink): 1/2 HP minimum
- Basement full-bath (toilet + shower + sink): 3/4 HP minimum
- Basement laundry room (washing machine): 3/4 HP recommended
- Basement wet bar or slop sink: 1/2 HP typical
- Below-grade kitchen (rare): 1 HP + commercial-grade pump
What Uses a Sump Pump
- Foundation groundwater (weeping tile drainage)
- Exterior drainage pits
- Landscape drainage
- NEVER sewage or wastewater
Common Ejector Pump Problems and Repairs
When an ejector pump fails, the sewage has nowhere to go but up — onto the basement floor. Here are the issues we see most.
Pump Won't Turn On
- Float switch stuck or broken — most common cause; pump can't sense water level
- Tripped breaker or GFCI — verify at panel, reset
- Failed motor — end of life; replace pump
- Bad control box (for hardwired systems) — test and replace
- Fix cost: $225 – $650 for float/switch; $725 – $2,400 for full pump replacement
Pump Runs but Doesn't Pump Water Out
- Clogged impeller — wipes, feminine products, or debris jammed (common in rentals)
- Failed check valve — water pumped out falls back into pit
- Clogged discharge line — buildup in the line preventing flow
- Worn pump — impeller and seals worn out
- Fix cost: $275 – $875 depending on cause
Pump Runs Constantly (Won't Stop)
- Float switch stuck in "on" position
- Check valve failed — pumped water falls back in, triggering re-pump
- Groundwater intrusion — cracked pit allowing groundwater (should be dry)
- Fix cost: $225 – $650
Bad Odor From Pit / Basement Sewer Smell
- Lid seal failed — gas-tight lid no longer sealing
- Vent line clogged or improperly terminated — Chicago requires 2" vent through roof, not into the attic or tied into another vent near the pump
- Dry trap on a fixture that uses the ejector (rare in active systems)
- Fix cost: $175 – $725
Sewage Backing Up Into Pit (Overflow)
- Pump failure while sewage continues flowing in
- Discharge line blocked (frozen, crushed, or clogged)
- Multiple simultaneous fixture use overwhelming undersized pump
- Emergency repair: $525 – $1,850+ depending on scope and time
Pump Cycles Too Frequently
- Pit too small for flow rate — pump cycles on/off rapidly, shortens life
- Float set too narrow — adjust high/low points farther apart
- Leak in discharge line — check valve or pipe leaking water back
- Fix cost: $185 – $525
New Ejector Pump System Installation
Adding a basement bathroom, laundry, or slop sink? You need a full ejector pump system. Here's what's involved.
System Components
- Ejector pit — 18" – 24" diameter × 24" – 30" deep fiberglass or HDPE basin
- Ejector pump — 1/2 HP for light duty, 3/4 – 1 HP for full bath/laundry
- Gas-tight lid — sealed lid with pass-throughs for discharge, vent, and electrical
- Discharge line — 2" schedule-40 PVC from pump up to sewer connection (typically 8 – 20 ft run)
- Check valve — prevents backflow; installed on discharge line near pump
- Ball valve — isolation valve for service/replacement; installed on discharge line
- Vent line — dedicated 2" vent through roof (Chicago code); cannot tie into other vents near pit
- Alarm — float-actuated high-water alarm; audible + WiFi optional
- Battery backup (recommended) — keeps pump running during power outages
Installation Process
- Plan and permit — Chicago DOB plumbing permit required for any new ejector installation
- Saw-cut basement floor and excavate for the pit (typically 3 – 4 ft deep)
- Set fiberglass or HDPE basin in the hole, leveled
- Pour concrete around the basin to anchor it
- Install the pump and connect discharge piping
- Run discharge line up and over to connect to main sewer (above the highest fixture served)
- Install gas-tight lid with all pass-throughs sealed
- Run vent line up through the wall to the roof (cannot tie into attic or other vents)
- Wire electrical — dedicated 15A or 20A circuit required
- Test — full fill/drain cycle test, leak check, lid seal verification
- City inspection before covering any work
Typical Cost Breakdown
| Item | Cost |
|---|---|
| Pit excavation + concrete | $850 – $1,850 |
| Ejector pit (fiberglass 18 – 24") | $275 – $550 |
| Pump (1/2 HP – 1 HP) | $375 – $1,200 |
| Gas-tight lid + alarm | $175 – $450 |
| Discharge piping + check valve + ball valve | $275 – $625 |
| Vent line through roof | $485 – $1,250 |
| Electrical circuit (if new) | $225 – $475 |
| DOB plumbing permit | $100 – $325 |
| Labor | $1,200 – $2,400 |
| Total | $3,200 – $6,800 typical |
Pump Sizing Guide
| Fixture Setup | Recommended HP | Flow Requirement |
|---|---|---|
| Basement half-bath (toilet + sink) | 1/2 HP | 30 GPM @ 10' head |
| Basement full-bath (toilet + shower + sink) | 3/4 HP | 45 GPM @ 15' head |
| Laundry + half-bath | 3/4 HP | 50 GPM @ 15' head |
| Full basement apartment (kitchen + bath + laundry) | 1 HP | 70+ GPM @ 20' head |
Maintenance to Extend Pump Life
A well-maintained ejector pump lasts 10 – 12 years. A neglected one fails in 4 – 7.
Annual Maintenance (30 Minutes)
- Lift the lid (carefully — gas-tight seal needs to be re-seated properly after)
- Inspect water level — pump should cycle every few days if fixtures are used; pit should not be dry or overflowing
- Test float switch — manually raise the float, verify pump activates
- Check alarm battery (if equipped) — annual battery replacement
- Clean debris from the pit (wipes, feminine products, etc.) — never flush these
- Test check valve — verify water doesn't fall back in after pump shuts off
- Re-seat lid gasket with fresh sealant if seal is compromised
What NOT to Put in an Ejector Pump System
- Wipes (including "flushable" — they aren't)
- Feminine hygiene products
- Diapers
- Paper towels
- Fats/oils/grease
- Medications
- Cat litter
- Anything that isn't toilet paper or actual bodily waste
Warning Signs Your Pump Is Failing
- Running more frequently than it used to (weakening impeller)
- Gurgling sound when toilet flushes
- Occasional basement odor
- Pump runs longer each cycle
- Higher electric bill
Address these early — $325 for a float swap now beats $3,000 for flood remediation later.
Battery Backup: Strongly Recommended
A power outage with a basement bathroom is a disaster scenario. Recommended addition: sump-pump-style battery backup that takes over during power failures.
- Cost: $550 – $1,450 installed
- Runtime: 5 – 12 hours depending on battery size and pump draw
- Protects against: storm outages, tripped breakers, failed switches
- See battery backup installation for details
Frequently Asked Questions About Ejector Pump Services
What is an ejector pump and do I need one?
An ejector pump moves sewage and wastewater from below-grade fixtures (basement bathroom, laundry, wet bar, slop sink) up to the main sewer line. You need one if any plumbing fixture is below the level where gravity alone can drain to the sewer — very common in Chicago basements. It's different from a sump pump, which only handles clean groundwater. Sewage ejector pumps must handle 2" solids and require sealed pit, gas-tight lid, and dedicated vent per Chicago code.
How much does ejector pump replacement cost in Chicago?
Just the pump replacement (existing pit): $725 – $1,650 for 1/2 HP, $1,250 – $2,400 for 3/4 – 1 HP. Full new system installation (excavate pit, install pump, all plumbing): $3,200 – $6,800 depending on scope. Minor repairs (float switch, alarm, check valve): $225 – $650. We provide upfront pricing before work starts.
How long do ejector pumps last?
Quality ejector pumps (Zoeller, Liberty, Hydromatic) last 7 – 12 years with proper maintenance. Budget pumps from big-box stores last 4 – 7 years. Lifespan depends heavily on what gets flushed — wipes, feminine products, and paper towels dramatically shorten pump life by clogging the impeller. Annual inspection extends life.
What's the difference between a sump pump and an ejector pump?
A sump pump handles clean groundwater to prevent basement flooding from the perimeter drainage system — it's in an open or vented pit. An ejector pump handles sewage and wastewater from below-grade plumbing fixtures — it's in a sealed pit with gas-tight lid and dedicated vent through the roof. They serve completely different purposes and are NOT interchangeable. A homeowner using a sump pump to handle sewage is a code violation and a health risk.
Why does my ejector pit smell bad?
Three common causes: (1) gas-tight lid seal failed — gasket old or lid not seated properly, (2) vent line issue — dedicated 2" vent to roof is clogged, or was wrongly tied into another vent, or terminates in the attic instead of outside, (3) dry trap on a fixture served by the pump — pour water to reseat. Repair cost $175 – $725 depending on cause.
Can a flushed wipe really destroy my ejector pump?
Yes — wipes (including "flushable" brands) are the #1 cause of premature ejector pump failure. They don't break down like toilet paper. They wrap around the impeller, clog the discharge, jam the float. A single flushed wipe can burn out a $600 pump. We replace dozens of pumps each year where the homeowner is surprised by what we pull out — "flushable" doesn't mean safe for ejector pumps. Only flush toilet paper and human waste.
Do I need a permit for ejector pump installation in Chicago?
Yes — new ejector pump installation requires a Chicago DOB plumbing permit with city inspection before covering any work. Like-for-like pump replacement (existing pit, existing discharge): usually no permit. Adding a new fixture served by the ejector (e.g., new basement bathroom): requires building permit + plumbing permit. We pull all permits and coordinate inspector visits.
What happens if my ejector pump fails during a power outage?
Without power, the pump can't run — and sewage continues flowing into the pit from any fixture use. A typical basement bathroom can overwhelm the pit in 30 – 90 minutes, flooding the floor with raw sewage. Prevention: (1) don't use basement fixtures during outages, (2) install battery backup (strongly recommended, $550 – $1,450), (3) install high-water alarm with loud audible siren so you know when capacity is reached. For active backups during outages, call our 24/7 emergency service.
Can I replace the ejector pump myself?
Not recommended — and many insurance policies won't cover damages from DIY pump work. Reasons: (1) sewage exposure is a biohazard requiring PPE, (2) the pump is heavy (40 – 80 lbs) and lifting it out of a deep pit requires proper rigging, (3) discharge connections must be leak-free, (4) float switch adjustment is critical, (5) sealed lid must re-seat perfectly gas-tight, (6) Chicago permit and inspection rules vary by scope. A licensed plumber install costs $725 – $2,400 — worth the professional handling and warranty.