Garbage disposals are all about convenience—in theory. Not having to scrape their dinner plates into the garbage like an animal might not seem all that crucial, but the people who have them (roughly half the homes in the U.S. have one installed) are pretty happy about that. There’s also an environmental argument in their favor, having to do with the amount of methane generated by food scraps in landfills versus treating those scraps in properly-equipped wastewater systems.
In practice, however, the benefits of a garbage disposal don’t go much beyond convenience, and even that is much more limited than you think, especially over the long haul. In fact, garbage disposals can cause more problems than they solve, and you’re probably better off without one.
Garbage disposals are finicky
Yes, the biggest benefit of a garbage disposal is time-saving—instead of having to scrape your dishes separately into the garbage or compost, you just scrape them into the sink, grind it all up, and get on with your day.
Except, of course, you have to be careful about what you put down your garbage disposal. Garbage disposals are super finicky, and there’s a long list of stuff you shouldn’t put down there, including random items like eggshells and celery? Once you start listing all the things you’re never supposed to put into your garbage disposal, you have to start to wonder just how convenient they actually are.
(If you don’t want to put your food scraps in the garbage, forget the garbage disposal and consider composting instead.)
Garbage disposals require constant maintenance
Garbage disposals aren’t magic black holes where all your culinary and food waste sins vanish. They’re actually pretty delicate things that require constant maintenance. They can jam—and do, a lot, which can find you jamming a broom handle into your disposal at midnight after a party, cursing the day you ever installed the damn thing. In order to keep your running smoothly, the short list of things you’re supposed to do on a regular basis includes
Sharpening the blades
Cleaning the unit
Running and flushing it regularly
Deodorizing
And that’s just to keep the unit functioning. And that maintenance is worth it, because if your disposal breaks, it’ll cost an average of about $500-600 to replace it, and $100-$250 to repair it.
Garbage disposals stress infrastructure
Depending on the age of your home’s plumbing and the condition of your local wastewater processing system, your garbage disposal can cause huge problems. Our country’s wastewater processing infrastructure is not exactly robust, generally speaking, which is why some municipalities prohibit garbage disposals (they were actually banned in New York City until 1997). One plumbing professional’s description of the process of using your garbage disposal makes it clear why they put so much stress on both your home’s plumbing and your town’s resources:
Imagine a giant ready-mix concrete truck filled with a slurry of sand, small rocks and water. Drop the chute and discharge this mix into a 12-inch-diameter city sewer. If you don’t add a significant volume of clear water immediately after dumping the sand and gravel into the sewer pipe, the pipe will start to choke off.
While some areas have wastewater systems that can handle the “slurry” created by garbage disposals, for many it’s a constant stress on the sewage and water processing systems. And there’s another potential problem that’s been linked to garbage disposals: Fatbergs.
Because we’re scraping food waste into garbage disposals, fat and grease enters the wastewater, where it builds up, sort of like cholesterol in your arteries, forming clogs that eventually stop sewage flow dead. A few years ago Seattle, Washington traced sewage backups to fatbergs, and garbage disposals were determined to be one of the biggest contributors to the problem. Admittedly, this is largely due to people using their disposals improperly—but it stresses just how limited these devices really are.
Garbage disposals waste water
Finally, garbage disposals waste water. Their effective operation requires water—once the scraps are ground up, you need to flush it into your pipes, and then into the sewer system. You should be running the water before you start the disposal, and let it run until about 30 seconds after the grinding is finished.
That’s all water going to waste, of course—about 2 to 5 gallons each time you run the disposal. If you’re running your disposal once a day, that’s 14-35 gallons every week. We already waste about 95% of the water we use every day, and having a garbage disposal just exacerbates that problem.