Sump & ejector pumps · Boulder, CO
Sump Pump and Ejector Pump Repair in Boulder, CO
A sump pump removes groundwater from a pit in the basement floor, and a sewage ejector pump lifts wastewater from basement fixtures up to the sewer line. They look similar and both sit in a basin, but they do different jobs and fail in different ways. B&D Plumbing repairs and replaces both in Boulder homes, with 24/7 service when a pump quits during a storm or a basement bathroom backs up.
What Is the Difference Between a Sump Pump and an Ejector Pump?
A sump pump moves clean groundwater out of the house, while an ejector pump moves sewage from below-grade fixtures into the sewer.
| Sump pump | Sewage ejector pump | |
|---|---|---|
| What it moves | Groundwater from foundation drains | Wastewater from basement toilets, showers, laundry |
| Basin | Open or loosely covered pit | Sealed, gas-tight basin with a vent |
| Where water goes | Outside, away from the foundation | Into the building sewer |
| When it runs | After rain, snowmelt or irrigation | Every time a basement fixture drains |
| Failure sign | Water on the basement floor | Basement fixtures stop draining, alarm sounds, sewer odor |
Groundwater from a sump pump belongs outside, not in the sanitary sewer. Clean water sent into the sewer adds load to sewer mains during storms, when they are already full.
What Are the Signs a Sump or Ejector Pump Is Failing?
The most common signs are a pump that runs constantly, a pump that hums without moving water, loud grinding, and water rising in the basin without the pump starting.
Sump pump warning signs
- Pump does not start when you pour a bucket of water into the pit
- Pump runs and runs with little water coming out (worn impeller or a clogged intake)
- Pump cycles on and off every few seconds (failed check valve or a float set wrong)
- Float sticks against the side of the pit
- Water around the pit or damp walls after rain
Ejector pump warning signs
- High-water alarm sounding
- Basement toilet or shower slow to drain or backing up while the upstairs drains fine
- Sewer odor near the basin (damaged lid seal or vent problem)
- Pump running continuously or tripping its breaker
Why Pumps Matter in Boulder Basements
Many Boulder homes have finished basements in clay soil, and clay drains slowly, so water from rain, snowmelt and irrigation collects around foundations. Foundation drains carry that water to the sump pit, and the pump is the only thing moving it out. Boulder's expansive clay adds a second reason to care: wet clay swells and pushes on foundation walls and slabs, so keeping water away from the house protects more than the carpet.
Heavy rain is when pumps fail and when they are needed most. During the September 2013 flood, basements across Boulder took on water. Homes along North Boulder's creek corridors and other low spots sit closer to a high water table. For split-level and basement bathrooms below the sewer line, common in Table Mesa split-levels, the ejector pump is the only way those fixtures drain at all.
How Is a Sump or Ejector Pump Repaired or Replaced?
- Diagnose. Test the float and switch, check power and the breaker, run water through the system, and listen to the pump under load.
- Repair what can be repaired. Free a stuck float, replace a failed check valve, clear a clogged intake screen, or replace a switch.
- Replace the pump when needed. A pump with a burned-out motor or worn impeller is replaced with a unit sized for the basin and the lift height.
- Check the discharge. For a sump, the discharge line runs outside and away from the foundation, with no freezing low spots. For an ejector, the discharge connects to the building sewer with a check valve and shutoff.
- Seal and vent ejector basins. The lid gets a gas-tight seal and the vent is confirmed open.
- Test under real conditions. Fill the basin, watch a full cycle, and confirm the alarm works.
Add-ons worth considering: a battery backup sump pump for power outages during storms, and a high-water alarm on any basin that does not have one.
What Affects the Cost of Sump or Ejector Pump Work?
Pump work cost depends on whether the pump can be repaired, the type and size of replacement, and the condition of the basin, check valve and discharge line.
- Repair or replace: a float or check valve is a small job, while a new pump is a larger one
- Pump type: sewage ejectors cost more than sump pumps and need sealed basins
- Horsepower and lift needed for the height and distance to the discharge point
- Discharge line changes, such as rerouting a sump line that freezes or drains back toward the house
- Battery backup or alarm additions
- Cleanup when an ejector basin has to be opened and pumped out
When Is a Pump Failure an Emergency?
A pump failure is an emergency when water is rising in the basement during rain, or when sewage is backing up from basement fixtures. For a sump, check the breaker and that the pump is plugged in, then call. For an ejector, stop using all basement fixtures and avoid using upstairs fixtures that drain to the basin. Call for emergency plumbing service any hour. If the backup is coming up the floor drain rather than from the ejector basin, the main sewer line may be blocked instead. See main line drain cleaning.
How Do You Maintain a Sump Pump?
To maintain a sump pump, test it each spring before the wet season by pouring a bucket of water into the pit and watching it start, empty the pit and shut off. Keep the pit free of debris, make sure the float moves freely, and check that the outdoor discharge is clear of snow, ice and leaves. Ejector pumps need less hands-on attention, but they should never receive wipes, grease or anything other than toilet paper. For other basement plumbing, B&D Plumbing provides complete plumbing services in Boulder.
Sump and Ejector Pump Questions
Should a sump pump drain into the sewer?
No. A sump pump discharges groundwater outside, away from the foundation. Clean water sent into the sanitary sewer adds to the load on sewer mains during storms.
Do I need a battery backup sump pump?
It depends on how much water your pit takes in and whether your basement is finished. Storms that fill sump pits often knock out power too, which is exactly when a primary pump stops.
Why does my sump pump run when it is not raining?
Irrigation, snowmelt, a high water table or a leaking water line can all feed the pit. A pump that cycles every few seconds usually has a failed check valve letting water fall back into the pit.
Can a basement toilet work without an ejector pump?
Yes, if the toilet sits above the sewer line so it drains by gravity. Fixtures below the sewer line need an ejector pump or an up-flush system to lift the waste.
Pump Not Running? Water Rising?
Call B&D Plumbing at (720) 571-0891, any hour. We repair and replace sump and ejector pumps in Boulder basements.
Licensed plumber · Answered 24/7 · 2525 Frontier Ave, Boulder