Water In Your Sump Pump? Here Are 5 Possible Reasons Why and What You Should Do Next

If your sump pump isn’t draining, is it time to dump your pump?

Basement living room tv stairs
Photo: FOTOGRAFIA INC. / Getty Images
Basement living room tv stairs
Photo: FOTOGRAFIA INC. / Getty Images
Timothy Moore
Written by Timothy Moore
Contributing Writer
Joseph Wood
Reviewed by Joseph Wood
Master Plumber
Updated January 25, 2024

Highlights

  • The positioning of your home itself can cause your sump pump to fail.

  • Problems often occur at either the discharge line or the discharge line valve.

  • While some remedies are DIYable, sump pump professionals usually charge $400 and $550 to repair a sump pump—or $500 on average to replace it.

Get quotes from up to 3 pros!
Enter a zip below and get matched to top-rated pros near you.

Whether 1 inch of rain falls or 4, it doesn’t matter. Somehow your sump pump pit is always about to overflow with water. What gives? The very point of a sump pump is to deter water away from your home and prevent flooding. So if there’s water constantly running into your sump pit above the normal level, you likely have a problem that needs attention—not to mention a very annoying humming noise you’d like to get rid of.

There are a few common reasons why your sump pump may be water-prone. Read on to diagnose your issue and learn the steps you can take to fix it.

1. Clogged Discharge Line

The discharge line moves the water from the pit to the storm drain or yard area away from your home. If the pipe or the sump pump basin gets clogged, the system won’t drain the water it captures, and water will pool around the pump.

Clogged Discharge Line Solution

This is a pretty common plumbing problem, as discharge lines can get clogged with anything from dirt to pebbles to tennis balls. It’s possible to unhook and unclog the discharge line yourself; just make sure it’s disconnected from any electrical source before you start fiddling with any line.

However, if sediment buildup is clogging the discharge line, you may enlist a local sump pump professional to help. Sediment usually gathers in the middle of the pipe, which is hard to reach without the special tools only a pro could source.

2. Frozen Discharge Line

Discharge lines don’t just get clogged; they can also freeze. If you live in a climate where the temperature frequently drops below 32 degrees Fahrenheit, your discharge line will likely freeze at least once and lead to continuous water in the sump pump.

Frozen Discharge Line Solution

This is a pretty easy fix; just melt the ice with boiling water. First, shut off power to the pump via your circuit breaker and remove any standing water with a wet vac or a hand pump. Next, bring a space heater near the pump—but far enough away from the pit to avoid electrical shocks—and turn it on to increase the surrounding temps and begin thawing the ice.

Then, boil a large pot of water and pour the boiling water into the pit. If you have a discharge pipe that comes apart in sections, take it apart and pour boiling water into the pipe to melt ice that may have frozen inside it.

3. Float Sensor Problem

Sump pump basement bucket
Photo: Robin J. Gentry / Adobe Stock

The float sensor triggers your pump to turn on and off when the water level in the pit reaches a certain point. The sensor is actually a round ball that floats on the water's surface, and when the level gets too high, it triggers a switch that drains the pit. If the float sensor malfunctions, it won’t trigger the pump to drain the water.

There are three basic reasons that float sensors fail:

  • Old age (sump pump float sensors typically last for about seven years)

  • Power failure (pumps will shut off unless it has a battery backup, potentially messing with the float sensor) 

  • The sensor is stuck on the side of the float pit

Float Sensor Problem Solutions

For a quick fix, turn the pump on manually to drain the excess water. This is especially important if you’re in a bad storm with a lot of rain or snow, as the water will continue to run into the pit even if the sensor isn’t working.

If you suspect the sensor has failed, a pro can either repair or replace it. Sump pump plumbing repairs cost between $400 and $550. In many cases, it may be just as cost-effective to replace the entire unit; on average a sump pump replacement costs $500.

4. Faulty Valve 

Between your sump pump and the discharge line, there’s a valve that opens and closes to let water out of the pump. If the valve isn’t working properly, it will send the water back into your home. This is one of the most common reasons that sump pumps collect standing water.

Faulty Valve Solution

If you want to avoid recurring basement floods caused by your sump pump, you should call in a pro to locate and check the valve to determine if a replacement is necessary. Diagnosing a faulty valve can be a pretty tricky DIY, so it’s best to leave this one to the pros. Valves themselves cost around $20, so your repair budget will mostly be consistent with labor charges.

5. Your Water Table Is Too High

If you have a high water table, it means your home is positioned too close to the water under the ground. And a pump that’s installed too close to the water table will get submerged when there’s rain or snow. Unfortunately, repositioning your house away from the water table isn’t an option, so you need to consider alternatives.

High Water Table Solutions

There are a couple of ways you can solve this problem.

  1. Reposition the sump pit away from the water table. This will help keep the sump pump itself from being submerged in the water under your home. Though digging a new pit doesn’t require you to purchase a new sump pump, pros usually charge the same amount for digging a new pit as they do for installing a new pump. You’ll save on the money you would spend for the pump itself, but the installation cost to dig a new pit is the same. The cost to install a sump pump is around $1,300.

  2. Get a second sump pump. If you don’t want to reposition your current pit, you can buy another pump to put in the pit. Whether you get a pedestal sump pump or a water-powered sump pump, the cost can be anywhere from $60 to $400. Having a second pump may drive your electric bill up, but it will keep your home safe from flooding and protect your foundation and basement.

DIY Fixing the Sump Pump vs. Hiring a Pro

If there’s water constantly running into your sump pit, don’t put off repairs. While you might be able to take care of easy repairs on your own—like unclogging or unfreezing the discharge line—you should typically leave more major repairs to the professionals.

A sump pump contractor or general plumber can correctly assess the issue with your sump pump and recommend the right repair or, in some cases, total replacement. On average, a plumber costs $45 to $200 an hour. You can expect to spend between $400 and $550 to have a pro diagnose and repair your sump pump.

Need professional help with your project?
Get quotes from top-rated pros.
Learn more about our contributors
Timothy Moore
Written by Timothy Moore
Contributing Writer
Timothy is a home renovation, personal finance, and travel writer with more than a decade of experience in the industry.
Timothy is a home renovation, personal finance, and travel writer with more than a decade of experience in the industry.
Joseph Wood
Reviewed by Joseph Wood
Master Plumber
Joseph Wood is a master plumber and the founder of Boston Standard Company. He trained vocationally and received a college degree in telecommunications. Joseph used his hybrid experience to create Boston Standard Company, the leading residential plumbing, heating, cooling, and electrical company based in the City of Boston.
Joseph Wood is a master plumber and the founder of Boston Standard Company. He trained vocationally and received a college degree in telecommunications. Joseph used his hybrid experience to create Boston Standard Company, the leading residential plumbing, heating, cooling, and electrical company based in the City of Boston.
The homeowners guide to Wells and Pumps
From average costs to expert advice, get all the answers you need to get your job done.