If your sump pump is not working — especially with rain coming or water rising — first check that it has power (it may be unplugged or the breaker tripped) and that the float switch is not stuck. Pour water into the pit to test whether it kicks on. If it will not run, is making odd noises, or cannot keep up, call a plumber. Because a failed pump can flood a basement, a battery backup pump is strongly worth having for power outages and failures.
A sump pump quietly protects a basement from flooding by pumping out water that collects in the sump pit, so a failure often is not noticed until water is rising. If you suspect a problem — or want to check before a big storm — a few steps tell you whether it is working.
Start with power: confirm the pump is plugged in and that its circuit breaker has not tripped (a surprisingly common cause). Then check the float switch, the mechanism that turns the pump on as water rises — it can get stuck against the pit wall or jammed by debris, leaving the pump idle even as water climbs. Freeing a stuck float sometimes fixes the problem.
Test it by slowly pouring a bucket of water into the sump pit. A working pump should switch on and pump it out. If it does not start, runs but does not move water, makes grinding or unusual noises, or cannot keep up with incoming water, those point to a failing pump that needs a plumber.
The bigger lesson is about backup. Sump pumps fail most dangerously during the heavy storms and power outages when you need them most — a standard pump is useless in a blackout. A battery backup sump pump (or a water-powered backup) keeps protecting the basement when the main pump or the power fails, which is why many homeowners in flood-prone spots consider it essential.
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How do I test my sump pump?
Slowly pour a bucket of water into the sump pit. A working pump should switch on and pump it out. If it doesn't start or can't move the water, it needs attention.
Why did my sump pump stop working?
Common causes are lost power (unplugged or tripped breaker), a stuck float switch, debris, or a failing pump. Check power and the float first, then call a plumber if it still won't run.
Do I need a battery backup sump pump?
It's strongly worth it. Sump pumps fail most during storms and power outages — exactly when you need them — and a standard pump is useless in a blackout. A backup keeps protecting the basement.