Why Does Water Come Up In The Kitchen Sink?

Get your groans of ‘ew’ out now, because this is going to get gross. It’s a common problem in both new and old homes, in apartments and houses, in dorm rooms and mansions – water coming back up in the kitchen sink can happen to anyone. It’s disgusting when it does happen, and if it goes down (or rather, doesn’t go down) while you’re not home, it could overflow and cause water damage. No one wants to wake up in the morning to dirty sink water spilling onto the floor or stinking up the house, but unfortunately it’s probably the most common reason a plumber is called. But why does it happen? We’re here today to explain why water comes back up in your kitchen sink.


Your kitchen sink is actually much more complicated than just the pipes that you see when you open the cabinet door. The kitchen sink is usually connected to one of the main pipelines in the home, since it’s relatively centered to the rest of the home. Your dishwasher, washer and dryer, toilet, and shower are all most likely connected through a series of pipes that all have their own branches and funnel into the same main line that drops all waste to the sewer. Your home will essentially tell you when something is wrong with any of these pipes, and water coming up in your kitchen sink is one of them.


Usually, when water begins coming up out of your sink it’s because of a clog. You’re probably used to dealing with clogs by pouring a chemical solution down the sink/shower and waiting 20 minutes before flushing it with hot water, but these are not effective and can cause terrible damage to your plumbing system that will need to be handled by a professional. Clogs in the kitchen sink are incredibly common. Think about all the things that accidentally get sent down the garbage disposal that really should have found their way into the trash can. Things such as egg shells, coffee grounds, potato peels, and bacon grease can seem like they’re being sent to the great trash compactor in the sky when you put them down the sink, but they’re just lying in wait for the day when there’s so many of them that no water can get through.


Another big possibility for why you have water coming up in your kitchen sink is because of a clogged air gap. The air gap is the seemingly useless cylinder on top of your sink, to the side of the faucet handle. Its purpose is to provide an exit pathway for the waste and water produced by your dishwasher. Consider it a bit like the middleman in your kitchen – the air gap takes all of the waste water from your dishwasher while it’s cleaning and pumps it safely back through the garbage disposal. If for any reason the air gap gets clogged (say, last night’s leftovers didn’t break apart too easily), the waste water will flood your sink. The sink’s pipes are unable to process all that water at once, and it bubbles up to hang out in the sink’s basin.


Whatever the cause is, water backing up into your sink isn’t the end of the world. A simple snake is usually able to fix it, and you can actually DIY this repair. Like we said earlier, avoid chemical drain cleaners as they’re indiscriminate about what they break apart; last night’s seafood shells are just as broken up as, say, your pipes’ insulation. If snaking the system doesn’t fix it, you might have a more serious problem. In that case, don’t hesitate to call your plumber.

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