10 Things You Should Never Pour Down the Drain


Most people put all sorts of stuff down the drain, from cooking oils to banana peels or medicine. But some things just don’t belong there, unless you want to have serious plumbing issues and expensive repairs. Now repeat after me: the sink’s drain is not a garbage hole.

That being said, before you dispose of something else that might force you to call the plumber, take a look at some of the worst offenders that can clog, block and ruin your drain.



If you’ve ever cooked rice, then you surely know that rice grains can swell up and clump in water. This means that tossing it down the drain is not the best method to dispose of uncooked rice. According to Mark Dawson, chief operating officer at Benjamin Franklin Plumbing, rice is an absorbent food and “can expand in your pipes and contribute to clogs.”

If you want to get rid of rice leftovers without blocking the pipes, toss them into the trash bin. No need to call the plumber whenever you serve some risotto! For more house tips, check out 9 Hidden Dangers In Your Home You Shouldn’t Ignore.


Cooking oil

Many people make the mistake of pouring cooking oils down the sink, unknowingly causing clumps and clogs over time. Cooking oils usually solidify at room temperature, warns certified master plumber Elisha French, owner of Texas Plumbing Solutions, LLC., which means they can instantly form drain clogs. Not to mention its adverse effects on the environment.

Even oils such as olive oil can solidify in contact with cold water and cause buildups if you’re making a habit out of disposing it down the drain. The best way to dispose of cooking oils is to collect it in sealable containers. Once it solidifies, throw the container in the trash can.



Some things just don’t belong in the kitchen sink and flour is one of them. That’s because in contact with water, it coagulates and turns into a gluey paste that can wreak havoc on your drain and pipes. This kitchen staple can be so messy that it not only creates buildups, but it can block your drainage system completely.

The easiest way to get rid of excess flour is to add water and turn it into a paste that you can easily throw into the trash.


Coffee grounds

If you thought coffee grounds can easily be flushed down the drain, think again. Coffee grounds do not break down in the water, no matter what your next-door neighbor told you. According to Dawson, coffee grounds “can accumulate in pipes and cause clogs”. If you need something to compare it with, think about cement. This is exactly how soggy coffee grounds work inside the pipes.

Coffee grounds may not be good for your pipes but they can be good for your skin! Find out how right here!


Animal fat

Tossing that lovely greasy substance into the kitchen sink drain after frying some bacon or sausages, seems harmless. But it is far from it. “The problem is that the water and grease cool as [they] move through the pipes and solidify, attracting other debris and creating a blockage,” says Arizona-based plumber Mark Stevens with Forrest Anderson Plumbing and Air Conditioning.

Not only does the fat stick to the pipes and causes blockages but it can also turn rancid and release nasty smells.


Mashed potatoes

Mashed potatoes, or any type of potatoes for that matter, seem innocent enough to be thrown down in the garbage disposal but the truth is can cause significant plumbing problems. First of all, they are a type of starchy food, like pasta, and can easily coat the blades of your garbage disposal. Secondly, water does not completely eliminate them no matter how much you use.

The safest way to get rid of mashed potatoes is by wiping the container with a paper towel and throwing as much as possible in the trash.


Banana peels

Banana peels can cause serious plumbing problems if you carelessly throw them in your garbage disposal. The fruits may be soft but their peel is anything but and can easily get stuck in your drain pipes. Just like other fibrous materials, banana peels are rougher and have no problem “fighting” your disposal motor and drain.

More than that, according to Dawson, they can “develop into a paste that slows down the blades” and creates a serious pipe jam. Wouldn’t it be easier to throw banana peels in the garbage can?



Eggshells crack in no time, so, they shouldn’t cause any problems when they go down the drain, right? Wrong.  According to Dawson, eggshells are the cause of many plumbing problems. Their seemingly delicate membrane can turn into a sticky substance in combination with water and cling to the blades of your garbage disposal.

Whoever said that eggshells can sharpen the blades definitely didn’t take the time to test the theory!



When it comes to medicine, whatever you do, just don’t pour it down the drain! Your pipes are not at risk of being clogged but the chemicals in these products can actually enter the environment and cause serious damage. According to the United States Geological Survey, people throw more than 4,000 types of prescription medication, affecting the environment, polluting groundwater and soil, and hurting marine life. More than that, the chemicals can also reach drinking water.

According to the Environmental Protection Agency, there are free drop-off sites where you can turn in your expired or unwanted medication or you can simply seal them in a container and throw them in the trash.



Pesticides might be good in your battle against bugs, but they are not good for the environment, especially if your way to get rid of them is by pouring them down the drain. Apart from damaging your garbage disposal’s seals, they can eat through pipes, even in the case of new ones. According to EPA, pesticides can turn into a real health hazard if they reach the city’s water supply. Public wastewater treatment systems may not have the capacity to filter such chemicals, so these may end up in the drinking water, harming everyone who consumes it.

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