Published by All Systems Pros · Updated October 12, 2026
Immediate Safety Steps for a Flooded Space
Stay out of standing water if the power is still on. Do not touch the sump pump or enter a flooded area until electricity is safely disconnected at the main panel.
Sump pump failures during a storm create immediate electrical hazards. When water rises above the pump basin and floods a basement or crawlspace, submerged electrical outlets or appliances can electrify the water. Your first priority is physical safety, not property protection. If you can safely reach your main electrical panel without stepping into water or standing on a wet surface, turn off the breakers supplying the flooded area.
If the electrical panel is inaccessible, located in the flooded zone, or you are unsure how to proceed safely, evacuate the immediate area and contact your utility provider or a licensed professional. Never attempt to unplug a submerged pump, handle wet electrical cords, or wade into a flooded zone to manually activate the system.
Common Signs Your Sump Pump Has Failed
You will typically notice water pooling around the pit, a pump that remains completely silent despite high water levels, or a motor that hums continuously without actually draining the basin.
Recognizing a failure early can prevent extensive water damage. The most obvious indicator is rising water that breaches the top of the sump pit. Under normal conditions, the pump should activate automatically before the water reaches the floor level. If the water is high but the pump is silent, the unit is not receiving power or the internal switch has failed.
Alternatively, you might hear the motor running constantly or making a loud grinding noise. A pump that runs without lowering the water level is often dealing with a mechanical blockage, a broken impeller, or a frozen discharge line. In some cases, the pump may cycle on and off rapidly, a condition known as short-cycling, which quickly wears out the motor and signals an underlying issue with the check valve or basin size.
Why Sump Pumps Stop Working During Storms
Power outages, jammed float switches, clogged discharge pipes, and burned-out motors are the primary reasons sump pumps fail when you need them most.
Heavy storms bring a combination of high water volume and electrical instability. The most frequent cause of a non-working pump is a simple loss of power. Without a battery backup system, a standard primary sump pump becomes useless the moment the grid goes down. If power is active, the float switch is the next most common failure point. The float switch tells the pump when to turn on and off based on the water level. Debris in the pit or vibrations from the motor can push the pump against the side of the basin, pinning the float switch in the off position.
Discharge pipe issues also peak during severe weather. If the pipe that carries water away from your foundation becomes clogged with mud, ice, or debris, the pump will run continuously but the water will have nowhere to go. Finally, older pumps simply wear out. The strain of moving thousands of gallons of water during a major storm can cause an aging motor to overheat and fail permanently.
What You Can Safely Check
Without touching standing water, you can verify the power source, inspect the outdoor discharge pipe for visible blockages, and look into the pit to see if the float switch is trapped.
While you should never attempt hands-on electrical repairs or wade into floodwater, there are a few safe visual inspections you can perform. Start by checking the electrical panel to see if a breaker has tripped, assuming the panel is in a dry, safe location. Next, walk outside to where the sump pump discharges water away from your foundation. Ensure the end of the pipe is clear of leaves, mud, snow, or animal nests. If the pipe is blocked, clearing the exit point may allow the trapped water to flow freely again.
If the area around the sump pit is completely dry and safe to approach, you can shine a flashlight into the basin. Look for obvious debris like plastic, rocks, or heavy sludge that might be interfering with the float switch. If the switch appears pinned against the basin wall, do not reach into the water to move it. Instead, note the condition so you can describe it to a professional.
Understanding Battery Backup Systems
A battery backup sump pump is a secondary unit that automatically activates if your main pump loses power or fails mechanically during a severe storm.
Relying solely on a primary sump pump leaves your property vulnerable to the exact conditions that cause flooding. Severe storms frequently knock out the electrical grid, rendering standard pumps completely inactive. A battery backup system sits in the same pit but operates independently. It runs on a dedicated, heavy-duty battery that stays fully charged by your home's electrical system during normal conditions.
When the power goes out, or if the primary pump cannot keep up with the volume of incoming water, the backup unit detects the rising water and takes over automatically. These systems also provide a crucial safety net if the primary pump's motor burns out or its float switch jams. An integrated alarm typically sounds when the backup system activates, alerting you that the primary system has failed and requires professional attention once the storm passes.
Preventative Maintenance Before the Next Storm
Regular maintenance involves clearing debris from the pit, testing the pump mechanism by pouring water into the basin, and scheduling an annual professional inspection.
The worst time to discover a sump pump issue is during a torrential downpour. Preventative maintenance ensures the system is ready to handle high water volumes. Follow the pump manufacturer’s inspection and testing instructions. Do not reach into a wet basin, handle wiring, or clear debris while equipment may be energized. Have a qualified technician remove debris and test the float, pump, backup system, and discharge path when safe conditions and isolation cannot be confirmed.
If the pump struggles to move the water, makes unusual noises, or fails to activate, it requires professional service. An annual inspection by a licensed plumber is the most reliable way to maintain the system. A professional will check the electrical connections, test the check valve, clean the impeller, and verify that the discharge line is completely clear, ensuring your home remains protected when the next storm hits.
When to Call a Professional Plumber
Contact a professional immediately if the pump motor is dead, the basin is overflowing, electrical hazards are present, or you cannot safely access the equipment to determine the problem.
Sump pump replacement and diagnosis require specialized knowledge of plumbing and electrical systems. A licensed plumber can safely navigate the hazards of a flooded space and determine exactly why the system failed. If your pump has burned out, a professional will calculate the correct horsepower and pumping capacity needed for your specific property before installing a replacement.
They can also inspect the check valve, which prevents pumped water from flowing back into the pit, and ensure the discharge line is properly routed away from your foundation. Do not wait for the next storm to address a pump that is making strange noises, short-cycling, or struggling to keep up with moderate rainfall.
About All Systems Pros
All Systems Pros is a plumbing service company based in Monrovia, CA. The company lists Rheem ProPartner, A. O. Smith Certified Contractor, and Raypak credentials. These general guides help explain plumbing topics; equipment instructions and project requirements must be checked for the specific property.
