9 Items Plumbers Warn You to Keep Away from Your Drain

After a large meal or completing a painting task, it might seem convenient to dispose of liquids or even solids down the sink. However, certain materials can severely damage your plumbing. Avoiding these substances ensures your kitchen operates smoothly and your water remains clean. Discover nine materials that plumbing professionals advise against disposing of in your sink, ranging from coffee grounds to chemical cleaners.

1. Paint

“Paint includes toxic substances that can erode plumbing and must be discarded following local guidelines,” explains Kyle Leman, CEO and founder of Crossroads Foundation Repair.

Disposing of paint in the drain can pollute water systems and harm your plumbing. Always check the paint label for disposal instructions. When unsure, deliver unused paint to a facility specializing in hazardous waste disposal.

2. Grease, Fats, and Oils

While cooking, avoid disposing of fats, oils, and grease in the sink, as these dense substances can cause pipe obstructions.

“These materials can harden and create blockages in your plumbing and the broader sewer network,” notes Shlomo Cherniak, proprietor of Cherniak Home Services in Baltimore.

3. Fibrous Vegetables

Vegetables are frequently discarded into kitchen sinks, but fibrous varieties like onions, celery, corn husks, fruit peels, and artichokes should never go down the drain.

“Celery, artichokes, and onion skins can wrap around the disposal motor, causing blockages and disrupting water flow,” explains Cherniak. “These fibrous items can result in expensive repairs and significant inconvenience.”

Rather than disposing of them in the sink, consider composting fibrous vegetables or throwing them in the trash.

4. Starchy Foods

Starchy items such as potatoes and pasta should never be discarded in the sink, as they can lead to pipe blockages. Employ a sink strainer to stop these foods from entering the drain.

“Potatoes, rice, and pasta can absorb water and expand, forming a sticky mass that blocks pipes,” Cherniak explains. “Potato starch can cause disposal blades to jam, and peels can stick to pipe walls. Always use a strainer to trap starchy food remnants before they reach the drain.”

5. Household Cleaners

Avoid disposing of household cleaners in the drain, as they can harm plumbing and negatively impact the environment. Instead, deliver these cleaners to a designated hazardous waste facility.

“Numerous household cleaning products include harsh chemicals that can corrode pipes and disrupt septic systems,” Leman states.

6. Coffee Grounds

Coffee enthusiasts often dispose of coffee grounds in the sink, but this practice can severely harm plumbing. Instead, discard grounds in compost or the trash.

“Coffee grounds can build up in pipes, leading to blockages and costly repairs,” Cherniak explains. “Their oily nature causes them to stick together, obstructing water flow.”

7. Produce Stickers

Produce stickers, though small, are adhesive and can clog your plumbing. Remove these stickers from fruits and vegetables and throw them in the trash.

“Produce stickers can adhere to pipes, causing blockages, or become trapped in water treatment filters,” Leman explains.

8. Kitty Litter

Avoid flushing cat litter down the toilet, even if it’s marketed as flushable. Dispose of it in the trash instead. “Even so-called ‘flushable’ products can clump together and clog your plumbing,” Leman warns.

9. Eggshells

“Eggshells take a long time to break down and can accumulate, obstructing the flow in your pipes,” Cherniak explains. “They tend to cling to pipe walls, causing blockages.”

Rather than letting eggshells enter the drain, dispose of them in compost or the trash.