10 Things to Never Pour Down the Drain

Your drains and pipes work hard to keep your home’s plumbing system running smoothly. However, pouring the wrong things down the drain can damage pipes, clog drains, harm the environment and create unsafe sewer gas. Being mindful about what goes into your sinks and toilets can help prevent problems and keep your drains flowing freely. We share 10 things you should never pour down the drain.

Cooking Oil and Grease

Pouring oils, grease, fat and meat drippings down the drain may seem convenient, but these slippery substances quickly cool, congeal and stick to pipe walls. As layer builds upon layer, grease accumulates into clogs, blocking water flow and necessitating plumbing repairs.

Instead of putting grease down the drain, pour cooled grease, fat and oils into an empty can for the trash. Use paper towels to wipe greasy pans before washing. Scrape plates and cookware and dispose of food scraps in the trash before rinsing. A sink strainer catches stray grease and particles. Proper grease disposal keeps water flowing freely through pipes.

Coffee Grounds

The morning coffee is a ritual for many busy households. Unfortunately, dumping coffee grounds down the drain can spell drain disaster. Grounds compact and accumulate in pipes, joining up with oils and eventually causing stubborn clogs.

Rather than sending coffee grounds down the pipes, allow them to cool slightly before tossing them in the trash or compost. For better results, strain cooled coffee through a mesh coffee filter before pouring it into the sink. Avoid using the sink as a waste bin, and remember that coffee grounds belong in the trash, not clogging up your drain.

Produce Stickers and Plastic Packaging

Fresh fruits and vegetables make for a healthy diet, but their stickers and packaging do not belong down the drain. Produce stickers easily wash off produce and stick to pipes and hoses when sent down the drain. Over time, they can accumulate and contribute to clogs.

Plastic produce bags, tags, netting and twist ties can also snag on pipes on the way down, gathering other debris. Avoid pouring these plastics down drains or flushing them. Instead, remove and properly discard produce packaging in the trash before washing fruits and vegetables. Send only the produce down to help keep drains clear.

Egg Shells

Crushing up and washing egg shells down the drain seems like a simple way to dispose of them after cooking and baking. However, the thin membranes on eggshells can cling to pipes and accumulate over time. Their gritty texture also works like sandpaper to gradually scrape and damage drain walls.

Rather than sending shells down the drain, place them in a paper bag or cardboard egg carton and dispose of them in the compost or trash. The calcium in crushed shells makes an excellent soil amendment for gardens, while keeping plumbing systems running smoothly.

Drain Cleaners

You may be tempted to pour caustic drain cleaner down a stubborn clogged drain. However, these powerful chemicals corrode pipes and release toxic fumes. Safer solutions exist for clearing simple clogs. Baking soda and vinegar can break up grease, while boiling water may melt accumulated grime. Use a drain snake to physically remove stuck-on debris.

For severe clogs, call a professional plumber for assistance rather than using dangerous and damaging chemical drain cleaners. Avoid pouring corrosive drain cleaners down your pipes at all costs. The damage is never worth the risk when safer solutions exist. Invest in quality pipes designed for longevity instead.

Dental Floss

Winding floss around fingers and teeth to clean plaque makes for good oral hygiene. However, sending floss down the drain can tangle pipes and cause messy clogs. The string easily wraps around pipes and snares other debris passing by. Over time, wads of floss accumulate and completely block drains.

To avoid problems, refrain from rinsing floss down the sink after use. Place used floss in the trash instead. Also take care to catch any dropped floss rather than letting it wash away. Show your pipes some love by keeping dental floss out of drains.

Paper Towels and Tissues

Paper towels, tissues, napkins and wipes are designed to absorb messes, not travel through plumbing systems. Although they may flush down a toilet easily, these products can easily snag on pipes. As more debris piles on, significant drain obstructions occur.

Never flush paper products like paper towels or pour grease soaked paper towels down the sink. Use trash cans for proper disposal instead. Clogged drains often result when homeowners treat toilets and sinks like waste paper baskets. Get in the habit of putting all paper items in their place – the trash can – rather than the drain.

Kitty Litter

Cat owners frequently wash out litter boxes in sinks, sending gritty granules down the drain. While convenient, this habit can cause excess sediment to build up. Over time, enough litter will accumulate to obstruct water flow. As materials get lodged in the nooks and crannies of pipes, clogs quickly form.

Protect your plumbing by disposing of kitty litter in the trash. Dump litter boxes into the garbage carefully to contain mess and dust. Rinse boxes with a light spray before scrubbing clean. A drain cover catches any stray particles. With some mindfulness, cat owners can avoid plumbing problems caused by sending kitty litter down the pipes.

Paint, Solvents and Thinners

Latex and oil-based paints, solvents and thinners all spell disaster for your drains and plumbing. Even small amounts can coat pipes and accumulate into substantial obstructions. Latex paint dries into a hardened blockage while solvents and thinners melt pipe joints. These chemicals also corrode metal pipes and release toxic fumes.

The only place for paints, solvents and thinners is at proper waste disposal facilities. Allow brushes and rollers to dry fully before rinsing sparingly. Contain paint cans for appropriate hazardous waste disposal rather than dumping contents into drains. Avoid exposing plumbing and the environment to these dangerous chemicals.


Leftovers, sauces, oils and condiments – if it’s edible, it does not belong down the drain. Food particles easily cause obstructions and accumulate into major blockages. As it decomposes, food also attracts rodents and creates unpleasant sewer odors.

Scrap plates, pots and pans thoroughly before washing to remove leftover food for disposal in the trash or compost pile. Opt for sink strainers to catch small particles. While a waste disposal grinds up some foods, avoid pouring oils, grease, eggshells and fibrous produce. Remember that the drain is for water only. Proper food disposal prevents plumbing problems.


Household pharmaceutical waste has potential for both environmental damage and safety risks when poured down the drain. Drug compounds often pass through conventional wastewater treatment and accumulate downstream. Antibiotic residues also contribute to microbial resistance.

Avoid flushing unused pills to protect water supplies; they belong in the trash after mixing with coffee grounds or kitty litter. Check for medication take-back programs in your community for safe disposal options. Keep medications out of the water stream by disposing safely rather than putting drugs down the drain.


Your home’s plumbing pipes and sewer lines endure heavy use daily. Avoid pouring trash, chemicals and other inappropriate items down the drain. These substances can gradually build up, causing corrosion, hazards or blocked water flow. Protect the longevity of your plumbing, the environment and health of your family by only allowing water down the drain. Follow these guidelines for the top 10 things to keep out of your home’s drains for optimum performance.

Frequently Asked Questions on Things to Never Pour Down the Drain

What happens if you pour grease down the drain?

Pouring grease down the drain allows it to congeal and stick to pipe walls as it cools. Layer upon layer of grease eventually causes substantial clogs that block water flow.

Why you shouldn’t put egg shells down the drain?

Egg shells contain gritty membranes that can wear away your pipes as they pass through. Small shells pieces also accumulate and lead to eventual drain clogs that obstruct water.

Can you put coffee grounds down the drain?

Coffee grounds compact and accumulate along pipes when washed down the drain. They eventually contribute to significant clog formation. Allow grounds to cool and dispose of them in the trash instead.

What does ketchup do to pipes?

The sugars and starches in ketchup and other condiments promote build up that sticks to pipes. Ketchup can also accumulate with fats and oils to create substantial drain clogs over time.

Can I put cat litter down the toilet?

Flushing cat litter sends grit into your plumbing system that will gradually accumulate. Drain lines will become completely blocked as enough sediment from the litter builds up. Always dispose of litter properly in the trash.

Are dental floss bad for plumbing?

The stringy texture of floss easily wraps around pipes and snares debris floating by. Over time, substantial obstructions form from the wads of floss in drain lines. Always place used floss in the trash.

Why you should not flush baby wipes?

Although they may flush, baby wipes do not break down well in plumbing systems. They can easily snag on pipes and accumulate with other debris to cause drain obstructions. Never flush wipes.

Can I pour paint thinner down the drain?

Solvents like paint thinner melt plastic pipes and release toxic fumes. They also create flammable situations. Allow thinners to dry fully before proper hazardous waste disposal. Never pour them down the drain.

What removes grease build up in pipes?

Baking soda and vinegar works well to break up grease. Boiling water also melts congealed grease. Use a drain snake to physically remove debris plugs. Avoid chemical drain cleaners which corrode pipes.

How do you unclog a sink clogged with coffee grounds?

Try boiling water to melt the oils and help break up the grounds. Baking soda and vinegar can also help dissolve the clog. Use a sink plunger to force the clog out. Avoid harsh chemical cleaners. A sink strainer prevents future issues.

Key Takeaways on Things Never to Pour Down Drains

  • Cooking oils, grease and fat create slippery layers that gradually cause major clog formation in pipes. Allow to cool and dispose of in the trash instead.
  • Coffee grounds compact and accumulate over time, eventually blocking drains completely. Place cooled grounds in the trash or compost.
  • Plastics like produce bags and stickers can snag on pipes and accumulate. Remove all packaging before washing produce and discard in the trash.
  • Eggshell membranes wear away pipes over time. Discard shells in the trash or compost instead of flushing down the drain.
  • Corrosive drain cleaners damage pipes and release toxic fumes. Use safer methods like baking soda and hot water instead.
  • Dental floss easily wraps around pipes and causes substantial obstructions when flushed. Throw used floss away in the trash.
  • Paper towels and tissues easily clog drains. Never flush or pour these paper products down sinks or toilets.
  • Kitty litter sediment gradually accumulates and blocks drain lines completely. Always empty litter boxes carefully into the trash.
  • Paints, solvents and thinners corrode pipes and create hazards. Allow to dry fully before disposing of through proper channels.
  • Food particles quickly clog drains and attract pests. Remove all food waste before washing dishes and opt for a sink strainer.
  • Medications flushed down the drain can damage the environment. Mix with unappealing substances like coffee grounds before trash disposal.