Top 5 Reasons Your Garbage Disposal Is Leaking

Ditch the leak once and for all

waste disposal leak under the sink
Photo: Mariakray / Adobe Stock
waste disposal leak under the sink
Photo: Mariakray / Adobe Stock
Allie Ogletree
Written by Allie Ogletree
Contributing Writer
Updated October 19, 2023

Highlights

  • Worn or broken seals, clamps, gaskets, and drain lines can cause disposal leaks.

  • A loose sink flange can make it seem like your disposal is leaking from the bottom.

  • Always follow safety measures when working with water and electricity. 

  • File a water damage claim if you see signs of mold.

  • Replace a leaky garbage disposal if it’s over 10 years old.

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If you hear the pitter-patter of a leak collecting under your kitchen sink, then your garbage disposal could be leaking from the bottom. Before you have a mold problem on your hands, you'll want to act quickly so that you don’t have to chip in extra for water damage remediation costs. Here are five top reasons your garbage disposal is leaking from the bottom and ways for you to fix the problem fast.

Angi Tip
To reduce the risk of water damage caused by faulty appliances, make it a habit to check for signs of dampness, mold, and pooling water monthly.
Ryan Noonan
Content Editor, Angi

1. Worn Internal Seals

Garbage disposal units contain seals that keep leaks at bay. This seal is typically made using plumber’s putty, and it secures elements of your disposal together, like the flange. Over time, however, the seals inside your garbage disposal will wear out. When this happens, water in the sink can slip into your garbage disposal and leak out from the bottom. 

How to Fix It:

If you have worn internal seals in your garbage disposal, then you might not want to fix it at all. That’s because, if one seal is deteriorated, there is a good chance that more seals are deteriorating or have already deteriorated. Consider the age of your garbage disposal when factoring in whether you should replace it. A newer model may just need a little bit of additional plumber’s putty, but a model that’s five years or older could have more problems.

2. Worn Rubber Gasket

In between the disposal’s seal and your sink flange lies a rubber gasket. As with any rubber material—which naturally deteriorates over time—this gasket can become worn down from frequent use or after around five years. When the rubber gasket wears out, water can start to leak and drip out from the bottom of your garbage disposal. 

How to Fix It:

With your flashlight in hand, loosen the drain pipe to access the rubber gasket inside it. If the gasket is in poor condition, replace your gasket with a compatible replacement part, then secure the drain pipe back where it belongs.

3. Loose Metal Clamp

man using wrench under kitchen sink
Photo: Steve Cukrov / Adobe Stock

Not all garbage disposal leaks originate from the bottom of the disposal. Leaks coming from the sides of your garbage disposal could be a sign that you have a loose metal clamp on hand. The drain lines connected to your garbage disposal unit contain this metal clamp to secure the drain lines that connect your disposal to the sink or dishwasher. 

How to Fix It:

Rule out a loose metal clamp by tightening the screws before you go out and purchase new drain line materials. If the metal clamp is not secure, you can quickly fix the problem by either tightening the screws connecting the clamp using a screwdriver or by replacing a broken clamp.

4. Loose Drain Lines

Garbage disposals have two drain lines that connect the disposal to your kitchen setup. One of the drain lines connects your dishwasher to the disposal so that food particles can drain into the disposal. The other drain line removes waste that enters your garbage disposal so that it can enter the sewer system. 

How to Fix It:

If you can see signs of deterioration in the drain lines, then you'll need to invest in a new drain line. While you're inspecting the drain lines connected to the disposal, make note that the smaller drain line is for the dishwasher, while the larger drain line is for the sewer disposal. You'll need to choose the correct measurements when replacing a drain line to ensure that your garbage disposal has the correct sizes, or you'll continue to experience leaks. 

5. Defective Sink Flange

A leaky garbage disposal may not be what meets the eye. Sometimes, it's actually your sink causing the leak. If you have a defective sink flange, then this metal piece that goes inside the drain of your sink could be leaking water. When the water leaks around the sides of the flange, it can flow down to the disposal and look like your disposal is leaking from the bottom. 

How to Fix It:

If the plumber's putty that secures your sink flange has deteriorated, or the bolts securing the flange under your sink have come loose, you can easily remedy the issue and stop the leak. 

For loose bolts, tighten the bolts using a screwdriver. Repairing deteriorated putty requires a little more TLC. You’ll need to disconnect the garbage disposal, loosen the flange’s bolts with the screwdriver, unfasten the clamp, take the flange out of the sink, remove the old putty, apply fresh, new putty, press the flange back into the sink, then reassemble your garbage disposal.

What to Do When There’s a Garbage Disposal Leak

Repairman installing new garbage disposal
Photo: yunava1 / Adobe Stock

We've gone through the ways that you can fix a garbage disposal leak, but there are some steps you should take when you first notice a garbage disposal leak to help you avoid safety hazards.

  • Unplug the garbage disposal to prevent electrocution.

  • Clear out the space around the garbage disposal so that your belongings don't get damaged.

  • Wipe up any standing water with a towel.

  • Place a container underneath the disposal to catch water leaks.

  • Check your homeowners insurance plan to see if your homeowners insurance covers water damage.

  • Make an insurance leak claim as soon as you can document the damage.

  • Contact a local garbage disposal installer for issues you don’t feel confident about fixing.

How to Prevent Garbage Disposal Leak Damage

Whether you fixed your leaking garbage disposal or you've installed a new one and want to stop leaks from happening in the first place, having a solid maintenance plan can help prevent leaks from sneakily wreaking havoc on your beloved kitchen. 

Reduce the risk of damage from garbage disposal leaks by checking for dampness, mold, and pooling water on a monthly basis. It’s also a good idea to inspect your refrigerator, washing machine, bathroom sinks, and dishwasher for leaks as part of a comprehensive maintenance checklist. Lastly, learn how to check for mold to take action if you do find yourself with a leaky appliance.

Frequently Asked Questions

If the cost of repairing a leaking garbage disposal is close to the cost of replacing the disposal, then fixing the unit might not make sense. When deciding if you should repair or replace your garbage disposal, consider the age of your garbage disposal, the cost of the repair, and whether your garbage disposal has had other problems recently to help you decide if the cost of repairing the leak is better than the cost of replacing the disposal.

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Learn more about our contributor
Allie Ogletree
Written by Allie Ogletree
Contributing Writer
Allie is an Austin-based content writer specializing in home improvement, renewable energy, and deregulated energy markets.
Allie is an Austin-based content writer specializing in home improvement, renewable energy, and deregulated energy markets.
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