8 Reasons Your Garbage Disposal Is Leaking and How to Fix It

1. Worn Internal Seals

Garbage disposals are built with seals that help prevent leaking, often using plumber’s putty to hold parts like the flange in place. As time goes on, these seals can deteriorate. Once they’re worn down, water from the sink may start to seep into the unit and eventually escape through the bottom.

How to Fix It

If the internal seals in your garbage disposal are damaged, it might be smarter to replace the whole unit instead of trying to repair it. When one seal starts to fail, others are often not far behind. Think about how old your disposal is—newer ones might just need a quick seal-up with some plumber’s putty, but if it’s been in use for five years or more, more serious issues could be right around the corner.

2. Worn Rubber Gasket

Between the sink flange and the seal in your garbage disposal, there’s a rubber gasket that helps keep everything watertight. Like most rubber parts, it doesn’t last forever and can break down after years of use, often around the five-year mark. Once it starts to wear out, it can allow water to leak from the bottom of the unit.

How to Fix It

Using a flashlight, carefully disconnect the drain pipe so you can reach the rubber gasket inside. If the gasket looks damaged or worn, swap it out with a suitable new one. Once the new gasket is in place, reattach the drain pipe securely.

3. Loose Metal Clamp

Leaks from a garbage disposal don’t always start at the bottom—sometimes, they come from the sides. This could point to a loose metal clamp. These clamps are used to keep the drain lines firmly connected between the disposal and your sink or dishwasher, and if one becomes loose, it can easily lead to leaking.

How to Fix It

Before buying new drain line parts, check the metal clamp to see if it’s loose. Often, the issue can be solved just by tightening the screws with a screwdriver. If the clamp is damaged, swapping it out for a new one should stop the leak.

4. Loose Drain Lines

A garbage disposal is linked to your kitchen plumbing through two separate drain lines. One connects to the dishwasher, allowing leftover food bits to pass into the disposal. The other line carries waste from the disposal out to the main sewer line, helping everything flow out smoothly.

How to Fix It

If the drain lines show any wear or damage, it’s time to replace them. While checking them over, remember that the thinner line connects to the dishwasher, and the thicker one leads to the sewer system. When getting a replacement, make sure the new lines match the right size—otherwise, leaks could keep happening.

5. Defective Sink Flange

A leak that seems to be coming from your garbage disposal might start higher up. In some cases, the sink itself is the real problem—specifically, the sink flange. This metal part fits inside the drain opening, and if it’s damaged or loose, water can escape around its edges. As the water trickles down, it may appear as though the disposal is leaking from underneath.

How to Fix It

If the plumber’s putty around your sink flange has worn out or the bolts holding it in place have become loose, you can fix the leak fairly easily. To tighten loose bolts, simply use a screwdriver. Fixing worn-out putty is a bit more involved. You’ll need to disconnect the garbage disposal, loosen the flange bolts, remove the clamp, take out the flange, clean off the old putty, apply a new layer, reinstall the flange, and then reassemble the disposal.

6. Corrosion

Metal parts that are regularly exposed to water, particularly with salt, are prone to corrosion. This makes garbage disposals especially vulnerable. The small metal components in the motor and grinders tend to rust first. However, leaks can introduce water to areas that would usually stay dry, meaning corrosion could occur in various parts of the system.

How to Fix It

Inspect the disposal for signs of rust. If you spot any, you can try removing it yourself using an acidic solution, like vinegar. However, if the rust is widespread or has affected internal components, it’s best to contact an SD Appliance Repair professional. Since most parts of the disposal are affordable, they can usually replace the damaged ones easily.

7. Impeller (Blade) Damage

The components responsible for breaking down food aren’t like fan blades—they’re typically two pieces that push food against a grinding plate. These parts, known as impellers, tend to wear out quickly because they take the most impact. While replacing the impellers is usually affordable, it’s best to have a professional handle the repair due to safety reasons.

How to Fix It

It’s a good idea to hire a professional. Impellers are designed to crush food effectively, but they should only come into contact with food. A technician can replace them quickly, usually within an hour, saving you both time and effort.

8. Cracked Housing

A garbage disposal has numerous components that can wear down over time. Leaks may occur if the housing gets cracked from excessive or improper use, or from neglecting regular maintenance. If your disposal is approaching its 10-year mark and begins leaking, inspect the entire unit for any cracks.

How to Fix It

Cracks often appear around the motor and seals, so start by inspecting those areas. While you can use epoxy to seal the crack temporarily, it’s not a long-term fix and probably won’t hold. For an older disposal, cracked housing is a common issue, and in most cases, replacing the entire unit is the best solution.

When to Call a Pro for a Garbage Disposal Leak

Some problems, like tightening screws or replacing a seal, can be tackled on your own. However, for more serious issues, such as a cracked housing or damaged blades, it’s best to hire an SD Appliance Repair professional. Electrical work should always be left to experts due to safety concerns. Reach out to a local plumbing repair technician to get quotes and explore your options.