6 Things You Should Never, Ever Put Down Your Kitchen Drain

published Jan 23, 2023
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It can be tempting to throw scraps down the drain if you have a garbage disposal and/or a new-build house with modern pipes. But even though they look harmless, disposals can actually wreak longterm havoc on your pipes if you’re not careful. If you want to save yourself from a hefty plumbing bill later down the road, here are some of the things you should avoid throwing down your drain, no matter what.

Coffee Grounds

Most people have been guilty of this from one time or other. You have leftover coffee grounds from your French press or aero press, and down the sink it goes. After all, they’re small granular pieces. How much damage can they do to pipes? Apparently, a lot. Grounds are highly fibrous and tend to clump together in water while going down drains. This makes them hard to dissolve, and over time they can create obstructions or clogs that will require a professional to fix. Instead, toss them into the trash or, better yet, into a compost bin. (This one’s super cute!) They can also be used to fertilize your garden.

Cooking Oil

Have you ever wondered why some folks pour bacon grease or ground meat fat from a frying pan into an aluminum can? It’s because pouring it down the drain can clog it. While the oil might slide down the drain easily once it’s hot, it eventually cools, coating the inside of the pipes with its thick fat. Not only can this cause clogs, but the fat can also go rancid, emitting a stinky smell from the drain and causing a sewage backup in your sink. Instead, let the pan cool slightly and pour leftover oil into a can. Once the fat hardens, toss it into the trash. If you don’t have an aluminum can handy, here’s an easy TikTok hack: Line the drain with aluminum foil, creating a “cup” in the drain. Pour the grease directly in, and once cooled, roll the foil into a ball and put it in the trash. 


Don’t let any remnants of your rice dinner make it down the drain, even if you have a garbage disposal. Because rice is water-absorbent (it can swell up to four times its uncooked size when cooked) it could clump together and stick to the confined space. The same happens when rice is put through garbage disposal blades, turning it into a thick, starchy paste and promising pipe trouble down the line. It’s best to throw it in the trash or compost bin — if you’re a pro composter. (Experts say uncooked rice can potentially attract pests, while cooked rice can also lead to harmful bacteria.) However, avoid the compost bin if the rice is saturated in sauce or animal fats.


Eggshells are brittle and flimsy, so one would assume they would be safe for a garbage disposal or sink drain. But thanks to the membrane, they cling when they’re wet and pieces can wrap around the shredder ring. Those same piece can also get stuck in the pipes, hardening over time, or the sharp edges can catch things going down the drain after it, creating a blocking hazard. While they might not create a dam to clog your pipe, they can exacerbate a problem when other troublesome things get thrown down the drain, like rice and oil. 

Fibrous Veggies

Potato peels, carrot shavings, corn, and leftover asparagus bits are all very fibrous, meaning they won’t dissolve while going down your drain or garbage disposal and can eventually clog it. They tend to get “stuck,” so throwing them into a compost bin or trash can is best. 


Are you done with a small DIY project or have leftover paint from changing the walls? It might be tempting to pour the extra paint down the drain, but it will coat your pipes and harden, laying the groundwork for future clogs. The same goes with rinse water and washing your paintbrushes in the sink. Instead, clean the paintbrushes in a special solvent and wipe them down with paper towels. As for leftover latex paint, let it dry up. You can either let it air dry and harden or use things like kitty litter and sawdust to speed up the process. Afterward, throw it in the garbage. Remember, oil paint is considered a hazardous material, and you need to dispose of it at a local drop-off center. 

When removing water-based paint solvent from rinse water or cleaning solvent, before disposing of it, run the water or solvent through a few coffee filters to capture the paint. Once it’s dry, throw it in the trash if it’s acrylic or at a drop-off center if it’s oil. You can then pour the water down the sink. As for the solvent, you can either reuse it later or dispose of it at a hazardous waste facility. (But don’t throw it in the trash since some of the solvents are combustible and can be a fire hazard.)

This post originally appeared on Apartment Therapy. See it there: 6 Things You Should Never Put Down Your Kitchen Drain (and What to Do with Them Instead)