Dirty kitchen sink

12 Things You Should Never Put Down the Drain

Household drains are designed for the passage of wastewater. What they can’t deal very well with is solid waste.

Some foods can expand in the pipes, grease needs hot water and soap to remove it, and sticky substances can be a pain to get rid of once they are down the drain. There is all manner of waste that can slip down the drain that can and will cause you problems if you’re not careful.

Clogged pipes are not only a nuisance, but they pose a health hazard, too. When chemicals and compounds are caught in your drain, they may react with each other, and can emit hazardous gases into the air. On top of that, if you can’t use your sink, you can’t wash your dishes, fruits and veg, or hands.

Read on to discover the 12 items you should never throw down the drain.

1. Oils & Grease

Oily food in dirty pan

When you wash your dishes, the oils are diluted in hot, soapy water, but they can still clog your drain if released in large enough quantities. Oils are heavy, so they can easily sink into dips in the pipes, and when they sit and cool in the p-trap, they become very difficult to remove.

There will always be some oil or grease that makes its way down the drain when you wash your dishes but be sure to avoid pouring your excess used oil into the sink.

2. Pasta & Rice

This section includes almost every grain and grain-based food. When grains sit in water, they expand. If they are allowed to sit in your pipes for too long, they could block the entire opening.

Foods that are high in gluten, like bread or pasta, turn glue-like when they are soaked in water. They might not seem too difficult to clean from your plate, but unblocking a drain is a lot harder.

3. Egg Shells

Egg shells in a bowl

Egg shells can be composted, and they are great for your garden, so there are many ways to dispose of them that don’t include dropping them down the drain. If they do go down the drain, they break apart and become granular, almost acting like sand.

4. Coffee Grounds

Coffee grounds cause similar problems to eggshells. Coffee is already granular, and cannot be diluted, in its ground form, unless it is freeze-dried first. Anything granular will settle in your drain and cause blockages unless great volumes of water pass through at once. Think of it like sand in a riverbed.

5. Feces & Litter

Kitten in litter box

We are sure most people don’t mean to put feces down the drain, so we will treat it as unintentional. But we want to put the warning out there to help discourage such mistakes.

Feces that get caught in the drain will not only attract pests and bacteria, but will produce an unpleasant smell, too. Even cat litter can contain harmful chemicals that should not be brought near food preparation areas or hand wash stations.

6. Fruit Stickers

This goes for any stickers, really. It’s easy to lose a small sticker from the peel of a piece of fruit when washing or preparing it. These stickers may be small, but there is strength in numbers. They will stick to the walls of your pipes, and in time, combined with other stickers and foods, they can block an entire pipe.

7. Paper Towels

Paper towel in kitchen

Paper towels (and toilet paper) are designed to be absorbent, soaking up as much liquid as possible to break them down. When submerged in a pipe, they can expand more than you could imagine.

Be especially careful with sanitary towels that can expand up to four times their size. It only takes a few paper products to block a kitchen sink completely.

8. Cleaning Chemicals

Obviously, there are some chemicals that are intended for use in the sink, but that does not mean all of them are. Before you dispose of any chemical down your drain, check the instructions for proper disposal.

Some chemicals can block a pipe, while others could corrode the walls and cause a leak.

9. Paint

Dirty paint brushes

There are many places that will take your leftover or dried-up paint and dispose of it for you, so there is no need to dispose of it down the drain. Even if the paint is wet and diluted when you dispose of it, it can still start to coat the walls of your pipes, narrowing the opening and eventually leading to a blockage.

10. Medicine

Just as with chemicals, certain active ingredients might be fine for one purpose, but not for another. Some medicines can create a chemical reaction when mixed with other chemicals, and what can make you feel better when ingested might give you a headache and a blocked pipe when poured down the drain.

11. Pits & Peels

Vegetable peels and compost tin

Some people have garbage disposal units installed in their drains that can cut up peels and pits, but we still recommend composting if you have the space. On the other hand, if you don’t have a garbage disposal unit or space for composting, it’s best to throw the remains of your fruits in the garbage, as a normal sink drain is no place for such things.

12. Flour

While you are baking, it can be tempting to wipe down your countertop and rinse the floury cloth under the faucet.

Flour, just like bread and pasta, is a coagulant. If you mix flour and water, you get a rudimentary glue. When this substance hardens in your pipes, there is a great chance that the pipes will become blocked, and this glue-like substance can be very difficult to remove.

How Do I Know If My Pipes Are Blocked?

The most obvious sign of a blocked pipe is when the water does not drain from your sink. Unfortunately, by the time this happens, it is often too late for a simple solution. However, depending on what you need the sink for, you could leave it for a time and see if it drains on its own.

Keep a close eye on the sink, the surrounding area, and the pipes below. If you see a leak, it is a sign that the blockage is causing the water to back up and be forced out elsewhere.

If the sink drains on its own, it does not mean your problems are over. It might just mean that a small amount of water is getting through the blockage. If the sink backs up again, you will need to take steps to unblock it.

Plumber working under kitchen sink

You can usually notice over time if your sink is becoming blocked. When the water starts to drain more slowly, you will know a blockage is forming, and you have time to act before it becomes fully blocked.

What To Do If Your Drain Is Blocked

There are a few ways to deal with a blocked drain:

  • Pour boiling, soapy water down the drain.
  • Use a chemical solution intended for unblocking drains.
  • Purchase or rent a drain snake.
  • Remove the pipes and then the blockage.
  • Call in the professionals.
Hand putting chemicals down drain

Adhering to our advice above and remembering not to put any of those items down the drain will help keep your pipes free and clear. If you do have a blockage, no matter how slight, the key is to act before it worsens.

Here are two videos that will show you how to unclog a sink using a variety of methods.

6 Ways to Unclog a Sink with Standing Water
How to Unclog a Drain Using a Drain Snake

Care for your drains well, and you will have no problems.

Steven Doyle

Steven Doyle is a freelance writer specializing in high-quality information-driven content. Not only does he write about durable and buy-it-for-life (BIFL) products, he gets hands-on to find the very best.

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