If you’ve been (secretly) tossing coffee grounds down the drain — it might be time to think again. While rinsing your coffee grounds down the drain occasionally might not form a major clog, experts say regularly doing so can cause clogs to form, which then cause damage to your plumbing system. Even though coffee grounds appear as fine particles, they tend to clump together in your pipes, forming a clog — without most people even realizing it. But is it fine to put coffee grounds down the garbage disposal instead? Here’s why experts say not to place coffee grounds down the sink and how you should properly dispose of them instead.
How do coffee grounds clog your sink?
“Yes, coffee grounds do clog your sink. In fact, they’re actually one of the most common culprits I see,” says Dustin Smith, Owner & Founder at Smith’s Plumbing Services. “Coffee grounds act like fine sand: they don’t dissolve in water but settle in the low spots of your plumbing. They’re also hydrophobic, repelling water, yet absorbing oils and fats that go down your sink.
“When those combine, the result is a thick, paste-like sludge that coats your pipes and builds up over time. I’ve cleared countless drains packed with dense, tar-like material made mostly of coffee grounds bonded with grease. It’s stubborn, hard to flush out, and a surefire way to restrict water flow,” he shares.
Smith also does not recommend putting coffee grounds down a garbage disposal.
“A disposal doesn’t make coffee grounds disappear—it just grinds them into even smaller particles, which still settle and stick inside your pipes. In fact, I’ve seen many cases where homeowners rely on their disposal and still end up with major downstream clogs,” he says.
How to properly dispose of coffee grounds
We’ve established one thing — the best way to dispose of coffee grounds is to avoid putting them down the sink altogether.
Instead, “Throw them into the general garbage bin, or if you have plants or a garden, use them as compost. If you’re washing out a coffee pot, first, wipe the coffee grounds into the bin before rinsing it to prevent them from getting into the drain,” says Zhelyazko Yanchev, a plumbing expert at Fantastic Services.
Cynthia Traxler, Founder of Review-Reuse-Repair Blog, cautions against throwing coffee grounds in the trash. “Why throw coffee grounds away when there are so many great uses for them?” I recommend using coffee grounds as a scrubbing agent. You can mix them with your hair conditioner as an invigorating scalp scrub. You can mix them with a little dish detergent for scrubbing out a skillet. Adding some coffee grounds to liquid hand soap can help remove the smell of onions or garlic from your fingers,” she shares.
Some other innovative ways to dispose of coffee grounds include using them in the garden. Coffee grounds contain nitrogen, potassium, magnesium, and other important nutrients that can help your plants thrive. Many people also use coffee grounds in composting. “If you aren’t into composting yourself, there is someone out there who wants your extra coffee grounds, so ask around.”
