If you’re a coffee lover, you probably make your own at home some days. And whether you’re using a french press, a pour-over set up or something else, you’ll be left with coffee grounds. If you’re in a hurry, it may be tempting to dump them in the sink and let the garbage disposal handle it, but can you safely put coffee grounds down a garbage disposal? Or is that a recipe for a plumbing disaster?

This is absolutely not a plumbing question that you want to learn the answer to the hard way. So, we spoke to Destry Thompson and Jessie Cannizzaro, both experienced plumbers, to answer this question for you; read on to see what they had to say.

Can You Put Coffee Grounds Down a Garbage Disposal?

“The question isn’t ‘can you put coffee grounds down a garbage disposal’ but rather ‘should you put them down the disposal,'” Cannizzaro jokes. She explains that fats-be they from meats, dairy, cooking oil, or something else can coat your pipes. These coatings get thick and build up into large deposits. When coffee grounds go down the drain, they can get stuck in these fat deposits. This is the beginning of the problem.

Thompson adds that “coffee grounds don’t dissolve in water, so they can block up your plumbing. This might make your garbage disposal work less effectively and could lead to big problems later on.”  These trapped grounds are laying the groundwork for a major plumbing issue down the road.

Will Coffee Grounds Clog My Sink?

Coffee grounds are small, so it seems like they shouldn’t create clogs. But that’s an incorrect assumption. Thompson explains that “when coffee grounds go down the drain, they mix with other stuff like grease and soap scum, creating a big lump that eventually blocks the drain.”

Unlike with hair clogs down your bathtub, snaking your drain often isn’t enough to clear these clogs. Cannizzaro says that the snake will often bore through the fat deposits, creating a bit of a hole that water can drain through. But when you retract it, the loosened pieces will often get pulled back in and keep the sink gummed up. You may have shifted the clog enough to temporarily speed up your drain, but it’s still there— and the problem will quickly return.

Will Coffee Grounds Make My Sink Smell?

If you’re a coffee lover, you might think that the lingering smell in your drain is a pleasant idea. After all, who doesn’t love waking up to the comforting scent of coffee in the kitchen? But in this instance, you’d be wrong. Thompson cautions, “As [coffee grounds] build up in the pipes, they can trap other food bits and gunk…which can quickly create bad smells in your sink.”

Cannizzaro agrees; she stresses that the way the grounds get trapped in fat deposits is a perfect setup for them to catch other food particles. And the longer this goes on, the worse the clog will be, and the more trapped debris will rot. Soon, you’ll have a very smelly and expensive problem on your hands. As mentioned above, snakes aren’t enough to clear these clogs; you’ll most likely have to call in the professionals.

So there you have it; just because coffee grounds will fit down a drain does not mean they belong down there. Save yourself the hassle-and the money-and compost your used grounds or throw them away. Keep them far away from your drains!

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