Sump Pump Failed: Steps to Limit the Damage

With a sump pump failure, what to do first is check the simple causes: power, the float switch and the discharge line. If the pump will not restart within a few minutes, start moving water out of the pit by hand or with a spare pump, and lift everything off the basement floor. Most of the damage comes from the hours the pit overflows, so the goal is to shorten that window.

Sump pump failure: what to do in the first 15 minutes

1. Stay safe. If water is already across the floor and near outlets or cords, switch off the basement breakers from a dry spot before you step in. Leave the sump pump circuit on if you can identify it.
2. Check power. Make sure the pump is plugged in, press the reset button on the outlet if it has one, and check the breaker. During a power outage the pump is simply dead unless you have a backup.
3. Lift the float. Reach in with a stick or a gloved hand and raise the float switch. If the pump starts, the float was stuck against the pit wall or tangled in the cord.
4. Listen. A pump that hums but moves no water may have a jammed impeller or a blocked intake. Unplug it, clear stones and debris from around the base, and try again.
5. Check outside. Find where the discharge pipe leaves the house. In winter the end can freeze solid, and in any season it can be buried or blocked. A pump that runs but cannot push water out will cycle until it burns out.

How to get water out when the pump is dead

If the quick checks fail, you need another way to move water. A small utility pump or a replacement sump pump from a hardware store is the fastest fix. Many submersible pumps can be swapped by a handy homeowner: unplug the old pump, loosen the coupling at the check valve, lift the pump out and set the new one in. If that is beyond what you want to try with water rising, call a plumber and bail in the meantime.

Bailing with buckets works better than people expect when the inflow is slow. Carry the water outside and dump it downhill, well away from the foundation, so it does not run straight back to the weeping tile. A wet/dry shop vac can also pull water from the pit, though you will be emptying it often.

During a power outage, a generator run outdoors with a properly rated extension cord can power the pump. Never run a generator in the basement, the garage or near an open window.

Protecting the basement while the pit is high

• Move boxes, rugs, electronics and anything cardboard off the floor and onto shelves or upstairs.
• Lift furniture legs onto blocks or plastic lids.
• Pull stored items a little away from the walls, since water usually spreads along the perimeter first.
• Extend downspouts so they discharge well away from the house and clear window wells of leaves. Less water at the foundation means less water in the pit.
• Take photos of the pit, the water level and anything that got wet.

Drying out after a sump overflow

Water from a sump pit has passed through soil, so do not treat it like tap water. It carries silt and whatever is in the ground around the house. Hard surfaces such as bare concrete can be cleaned and dried. Carpet underpad and the bottom of finished walls are the usual problem. Drywall wicks water up from the floor, and the bottom plate of the wall sits wet behind the baseboard where you cannot see it.

If only bare concrete got wet, squeegee the water to the pit or floor drain, wash the floor and run a dehumidifier until it is dry. If finished walls or flooring got wet, the materials need to be measured. We check with a moisture meter and thermal camera, remove what cannot be saved, and dry the framing to under 16% wood moisture content with daily logged readings. Most water damage jobs here run $1,950 to $11,000, and you get a firm written quote within 2 hours of sending photos, between 7 am and 9 pm.

Keeping it from happening again

Sump pumps wear out, and they tend to quit when they are working hardest. In the London area, with clay-heavy soil that holds water against the foundation, that usually means spring thaw and big summer storms. A few inexpensive habits make a difference.

• Test the pump every few months by pouring a bucket of water into the pit and watching it start, pump and shut off.
• Add a battery backup pump or a water-powered backup so an outage does not leave you with nothing.
• Put a water alarm or leak sensor at the pit so you know when the level rises.
• Check the discharge outlet outside each fall and after heavy snow.
• Replace an old pump before it fails. If you do not know how old it is, treat it as due.

If your pump is running again, do the bucket test tonight and once more tomorrow. A pump that failed once without an obvious reason is telling you something.

Common questions