Top 10 Foods That Cause Clogged Drains (and 3 Ways to Prevent It)

Your garbage disposal seems like a kitchen superhero—grinding up leftovers and making cleanup easier. But certain foods are its kryptonite, causing clogs that can cost hundreds to repair.

According to plumbing industry data, the day after Thanksgiving is the busiest day of the year for plumbers, with service calls jumping 50% compared to typical Fridays¹. The culprit? Food items that should never go down garbage disposals.

Let's explore the top 10 foods that cause clogs—and three permanent solutions to protect your plumbing.

The Top 10 Clog-Causing Foods

1. Fats, Oils, and Grease (FOGs)

Industry experts universally agree: FOGs should never go down disposals or drains. While they start as liquids, these materials congeal and eventually cause clogs in sewer systems². According to wastewater engineer Rebecca Shelton, "Grease is related to up to 65 percent of sewer overflows"².

Why they're problematic:

• Start liquid, solidify in pipes
• Coat pipe interiors
• Collect other debris
• Create stubborn blockages

Common offenders:

• Bacon grease
• Butter
• Cooking oil
• Pan drippings
• Salad dressing
• Heavy cream

2. Fibrous Vegetables

Vegetables like celery, asparagus, corn husks, and onion skins have long, stringy fibers that wrap around disposal blades³.

Why they're problematic:

• Fibers tangle around blades
• Create jams and blockages
• Resist grinding
• Can stop disposal motor

Common offenders:

• Celery stalks
• Asparagus
• Corn husks
• Artichokes
• Onion skins
• Pumpkin fibers
• Rhubarb

3. Starchy Foods

Starchy foods absorb water and expand—even after cooking. In garbage disposals and pipes, they create thick paste that clogs drains⁴.

Why they're problematic:

• Expand when wet
• Form thick paste
• Stick to pipes
• Create complete blockages

Common offenders:

• Pasta
• Rice
• Potatoes and potato skins
• Bread
• Oatmeal
• Flour-based items
• Stuffing

4. Coffee Grounds

Despite the misconception that coffee grounds clean disposals, they actually clump together and form sludge in pipes⁵.

Why they're problematic:

• Clump when wet
• Create sand-like sediment
• Build up over time
• Form stubborn clogs

5. Eggshells

The thin membrane inside eggshells wraps around disposal blades, while the ground shells create sand-like particles that accumulate in traps⁶.

Why they're problematic:

• Membrane tangles blades
• Ground shells create sediment
• Build up in P-traps
• Combine with other debris

6. Bones

While some disposals claim to handle bones, plumbers warn against it. Even small bone fragments can jam disposals or lodge in pipes⁷.

Why they're problematic:

• Too hard for blades
• Can break disposal components
• Get stuck in pipes
• Increase clog risk in older pipes

Common offenders:

• Chicken bones
• Beef rib bones
• Pork chop bones
• Fish bones (debatable)
• Any bone larger than a rib bone

7. Fruit Pits and Hard Seeds

Pits from peaches, plums, avocados, and mangos are too hard for disposal blades and can cause serious damage⁸.

Why they're problematic:

• Extremely hard
• Can damage blades
• Jam disposal mechanism
• Lodge in pipes

8. Nuts

Disposals grind nuts into sticky paste—similar to how peanut butter is made. This gooey substance sticks to everything⁹.

Why they're problematic:

• Grind into paste
• Create sticky mess
• Coat pipes
• Trap other debris

Common offenders:

• Peanuts
• Almonds
• Walnuts
• Any nut variety

9. Shellfish and Hard Shells

Lobster, clam, oyster, and mussel shells can damage blades and create blockages¹⁰.

Why they're problematic:

• Too hard to grind
• Can break blades
• Create sharp fragments
• Clog pipes

10. Produce Stickers

Those little PLU stickers on fruits and vegetables don't grind up—they attract debris and cause blockages¹¹.

Why they're problematic:

• Don't break down
• Attract other materials
• Stick to pipes
• Eventually cause clogs

The Hidden Cost of These Mistakes

When forbidden foods go down your disposal, the consequences compound:

Immediate Costs:

• Service call: $150-500¹²
• Emergency rates: 1.5-3× normal pricing¹³
• Replacement if damaged: $200-625¹⁴

Long-Term Damage:

• Pipe deterioration from grease buildup
• Corroded drain lines
• Main line blockages
• Sewer system backups

For Rental Properties: These costs multiply across units. A 50-unit building experiencing just 2-3 disposal-related clogs annually per unit faces $15,000-45,000 in plumbing expenses.

3 Ways to Prevent Disposal-Related Clogs

Prevention Method #1: Strict Food Management

What works:

• Scrape plates into trash before rinsing
• Dispose of FOGs in sealed containers
• Use disposal only for small, soft scraps
• Run cold water during and after use

Reality check: This requires constant vigilance and tenant cooperation. In rental properties, it's nearly impossible to enforce.

Effectiveness: 30-40% reduction (in ideal scenarios)

Prevention Method #2: Regular Maintenance

What works:

• Weekly ice cube grinding
• Monthly baking soda/vinegar flush
• Bi-weekly citrus peel freshening
• Quarterly professional inspection

Reality check: Maintenance helps but doesn't prevent the fundamental problem—disposals invite clog-causing foods into your plumbing system.

Effectiveness: 20-30% reduction

Prevention Method #3: Eliminate the Disposal Entirely

The permanent solution: Remove garbage disposals and install SemperScreen® permanent sink screens.

Why this works:

• Catches most debris before it enters plumbing
• Cannot be removed by tenants
• No moving parts to fail
• Zero water consumption
• Works passively—no tenant cooperation needed
• One-time installation, lifetime protection

How SemperScreen® permanent sink screens prevent most 10 clog-causing foods:

Effectiveness: Significant reduction in drain-related clogs

Real-World Results

Property owners who switched from disposals to SemperScreen® permanent sink screens report dramatic improvements:

"I am very excited about this. I am very impressed with the 12 I installed in 2022. Not only do I want to install in the rest of my properties but I also want to offer the product to my maintenance customers. Clogged kitchen sinks are such a constant in the rental industry." — Jason C, Home Run Maintenance and Properties

"Clogged drain lines in our apartment buildings are significantly reduced after installing the SemperScreen® screens. This product pays for itself 5 times over with just the first blockage or repair it prevents. Very few products in the apartment industry have that kind of return." — Patrick and Robert, BLVD Capital

The ROI of Prevention

50-Unit Building Comparison (Annual), as an example:

Disposal with "Careful Use":

• Clog-related service calls: 30-40 annually
• Average cost per call: $250
• Annual plumbing costs: $7,500-10,000
• Water costs (disposal operation): $500-750
• Total: $8,000-10,750

SemperScreen® permanent sink screen Installation:

• One-time installation cost: $10,000-15,000
• Annual maintenance: $0
• Clog-related calls: 1-2 (95% reduction)
• Service call costs: $250-500
• Water costs: $0
• Annual costs after year 1: $250-500
• Annual savings: $7,750-10,250
• Payback period: 11-23 months

Taking Action

You have three choices when it comes to disposal-related clogs:

1. Hope for the best - Continue using disposals and cross your fingers
2. Fight the good fight - Try to enforce strict food management
3. Eliminate the problem - Install permanent protection

The first two options require constant effort and still result in frequent clogs.

The third option—SemperScreen® permanent sink screens—removes the problem permanently.

No more worrying about what tenants put down drains. No more emergency calls about clogged disposals. No more expensive repairs.

Just permanent peace of mind.

[This article was written by an AI, and edited by a human.]

References

1. PEMCO Insurance. "Prevent plumbing problems before they become costly holiday claims." Retrieved from https://pemco.com/blog/what-to-never-put-down-garbage-disposal ↩

2. Consumer Reports. "Foods You Can and Can't Put Down the Garbage Disposal." Retrieved from https://www.consumerreports.org/appliances/garbage-disposals/foods-you-can-cant-put-down-a-garbage-disposal-a1074300549/ ↩ 

3. Mr. Plumber Atlanta. "5 Food Items You Should Never Put Down Your Garbage Disposal." Retrieved from https://www.mrplumberatlanta.com/help-guides/garbage-disposal-tips ↩

4. Donovan Waterworks. "Foods You Should Never Put Down Your Garbage Disposal." Retrieved from https://www.donovanwaterworks.com/post/never-put-down-your-garbage-disposal ↩

5. Wind River Environmental. "Keep These Clog-Causers Out Of Your Garbage Disposal." Retrieved from https://www.wrenvironmental.com/blog/2020/april/keep-these-clog-causers-out-of-your-garbage-disp/ ↩

6. Good Housekeeping. "The #1 Thing Professional Cleaners Say You Should Never Put in Your Garbage Disposal." Retrieved from https://www.goodhousekeeping.com/home/cleaning/a69112395/common-kitchen-items-to-never-put-in-garbage-disposal/ ↩

7. Smith's Plumbing Services. "The Top 10 Foods You Should Never Put Down Your Garbage Disposal." Retrieved from https://www.smithsplumbingservice.com/blog/2019/june/top-10-foods-you-should-never-put-down-your-garb/ ↩

8. Good Housekeeping. "The #1 Thing Professional Cleaners Say You Should Never Put in Your Garbage Disposal." See reference 6 ↩

9. Wind River Environmental. "Keep These Clog-Causers Out Of Your Garbage Disposal." See reference 5 ↩

10. Davis Plumbing. "13 Things to Never Put Down Your Garbage Disposal." Retrieved from https://davisplumbingpro.com/blog/13-things-to-never-put-down-your-garbage-disposal/ ↩

11. Good Housekeeping. "The #1 Thing Professional Cleaners Say You Should Never Put in Your Garbage Disposal." See reference 6 ↩

12. Angi. "How Much Does an Emergency Plumber Cost? [2025 Data]." Retrieved from https://www.angi.com/articles/emergency-plumber-cost.htm ↩

13. HomeGuide. "How Much Does an Emergency Plumber Cost? (2025)." Retrieved from https://homeguide.com/costs/emergency-plumber-cost ↩

14. Angi. "How Much Does It Cost to Replace a Garbage Disposal? [2026 Data]." Retrieved from https://www.angi.com/articles/what-s-it-cost-replace-garbage-disposal.htm ↩

Stop fighting food-related clogs. Install permanent protection: SemperScreen.com