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Are Garbage Disposals Bad For Plumbing

Garbage disposals are typically installed as part of a home’s plumbing system. While they can make cleanup easier, they also have the potential to cause clogs and damage pipes in your home.

Garbage disposals are not bad for plumbing as long as they are used properly. Putting down stringy, fibrous foods or grinding food wastes without running enough water will cause clogs and eventually damage pipes.

Are garbage disposals bad for plumbing

Properly running and maintaining your garbage disposal is the key to avoiding clogging in the pipes. In this article, let me tell you how a garbage disposal works, why it can clog your pipes, and how to avoid this.

Working of a garbage disposal

A garbage disposal works by throwing food wastes at a stationary shredder ring with two impellers on a fast rotating disc. The lugs smash the food wastes and break them down into small particles which escape to the drain pipes through tiny holes in the shredder ring. It doesn’t have any sharp blades to cut food wastes like a blender.

However, a blender can help you understand what the ground food wastes in your disposal look like. Add some of your food wastes into a blender, add some water and run it. That sludge you see there is exactly how the food flowing out of a garbage disposal looks like.

What can cause garbage disposals to clog pipes

Here are the common reasons why garbage disposals clog drain pipes.

Old plumbing

If your house’s plumbing is too old, it may not be able to handle the extra load added by the garbage disposal. There can be deposits inside the old plumbing, which effectively reduces the space through which the sludge produces by the disposals go. Also, the insides of the pipes need not be smooth; they can be scaly, slowing down the water draining.

Clogs are a good indication of whether your current plumbing can handle a garbage disposal. If your drains clog often, or the water is draining slower than it should, adding a garbage disposal will make it only worse.

Having a septic tank

Garbage disposals are generally not recommended to be installed if you have a septic system. It works well as long as you have a properly sized spetic tank, but unfortunately, there is no way to know if yours is ‘properly sized’.

If your septic tank is not large enough to handle the additional load added to it by the garbage disposal, it will lead to draining problems.

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Overloading the disposal

Overloading the garbage disposal is a sure way to cause clogs. There is a good reason why plumbers like me are busy on the days after Christmas and thanksgiving. When people put down everything together into the disposal, that is like trying to fit a quart into a pint pot. Your garbage disposal won’t be able to handle such huge loads. This will cause it to jam, eventually leading to clogs and drainage issues.

Adding greasy, fibrous foods

Another reason for clogged pipes is adding food wastes that shouldn’t be added to your garbage disposal. These items vary depending on the grinding ability of your garbage disposal. However, as a guideline, you shouldn’t put fibrous or slimy food wastes into it. These items are the number one reason behind plumbing problems.

Here is a list of things that can cause clogs in a disposal.

Lack of cleaning

Garbage disposals should be cleaned regularly. The ground food wastes can get between the grinding components making them less effective at their job. This can cause clogs within the garbage disposal and also in drain pipes. The accumulated food wastes will also rot, causing the disposal to smell. This will also make it a breeding place for gnats, roaches, and fruit flies.

How to avoid clogs when using a garbage disposal

Like I mentioned before, garbage disposal will cause clogs if not used properly. To avoid this, stop treating them like a trash can. That’s right; garbage disposals are not garbage cans; they are not the places to put everything not wanted in your house.

Run plenty of water

One way to avoid clogging is by running plenty of water when using a garbage disposal. Also, instead of adding all the food wastes in bulk, add them in smaller portions to make sure the food wastes are easily washed away. Remember the thick sludge in the blender? Just like it can be thinned by adding more water, you can make it easier for the drain pipes to handle food wastes by running plenty of water.

Run garbage disposal regularly

One should run arbage disposals regularly. If not used for a while, its grinding components can rust and refuse to move the next time you start it. Rusts can also make the grinding less effective. This will cause the disposal and the pipes to clog. Running the disposal regularly will give it the abrasive action its components need to keep the rust away.

Avoid overloading garbage disposals

Avoid overloading your garbage disposal by cutting large size foods into smaller pieces. Add the food wastes in small quantities instead of cramming them all together down the disposal’s throat. Give your garbage disposal the time to grind the foods. Add more only after the previous batch is ground.

Clean them regularly

Cleaning garbage disposals regularly keep their grinding components clean. This helps to break down food wastes effortlessly, reducing the chances of jamming. This will also avoid pests making homes in them.

Watch what you grind

As I said before, a garbage disposal doesn’t equal a trash can. It would help if you watched what you put in them. Avoid adding grease, oil, and fibrous vegetables to your disposal. It would be best if you also abstained from grinding hard food items that are not within the scope of your machine. If your garbage disposal can’t chew it, put it in the garbage can.

Infographics showing ways to avoid clogs when using a garbage disposal


By watching what you add and maintaining properly, you can use garbage disposals for a lifetime without clogging or damaging your plumbing.

Further Reading:

My name is Thomas Anderson, author of DisposalQA. I have 15 years experience working as a plumber in CA, and this is where I answer common questions about garbage disposals.