Invented in 1927 by John Hammes, the machine uses blunt impellers to grind food waste and send it to your local wastewater treatment facility, saving you from fishing scraps of food out of your sink after washing dishes and diverting waste from landfills (sometimes). Here’s what you need to know about how to clean and maintain your garbage disposal.
How to properly use your garbage disposal
It all begins with proper usage. The first thing to remember is to use only cold water when running it, which hinders residual fat and grease from building up in the machine. (Besides, you shouldn’t be putting fat, grease or oil down the drain to begin with.) Second, it’s probably not a good idea to run it while your sink is still full of dishes in case a stray fork or spoon should fall down the drain and potentially wreak havoc on the disposal’s insides.
When you’re ready to bid adieu to food waste, run cold water, turn on the garbage disposal, slowly feed in small food scraps and then let the water continue to run until the whirring slows to a gentle hum, 15 to 30 seconds, before turning off the disposal and then the water. (Large pieces of food waste should be cut into smaller pieces before disposing.) Running the disposal with water flushes food through the system, helping to prevent odors.
What can and can’t go in a garbage disposal
The guidance for what should and shouldn’t be fed into a garbage disposal can be contradictory, depending on the source. However, there are certain instances in which everyone agrees, such as do not put plastic, glass, metal and other items that aren’t food down the drain. Other items better suited for compost or the trash include large bones, clam and oyster shells (I’d stay away from all shellfish exoskeletons, just to be safe), and fibrous vegetables and scraps, such as corn husks, artichokes, onion skins and celery. While the manual for the model in my kitchen says that egg shells are okay, other manufacturers advise against them in large amounts, so I plan to toss them in the trash out of an abundance of caution. Plumbing experts also advise against starchy foods, such as pasta or rice, that expand when wet and can clog your pipes. Pretty much everything else is fair game to go down the drain, including small bones and fruit pits, which can help scour the grind chamber.
How to clean your garbage disposal and deal with smells
One site of potential smells and other general grossness to be wary of is the baffle, a.k.a. the rubber splash guard. Admittedly, I didn’t even think about it for the seven months I lived in my apartment until this past week, and let’s just say I will never neglect it for that long again. Thankfully, cleaning it is simple enough to do every couple of weeks or so, depending on how much waste you dispose of. The baffle is removable on some disposals, which simply means remembering to clean it with soap and water or run it through the dishwasher. If not removable, unplug your garbage disposal or cut off the power to it from the circuit breaker before cleaning the underside with a sponge or old toothbrush. (While there aren’t any sharp blades in garbage disposals, you still shouldn’t stick your hand inside without first turning off the power.) And while you’re in there, you should also clean the smooth, sloped area at the top of the grinding chamber.
If you do all of the above and still run across foul smells, fill the sink halfway with water, stir in 1/4 cup or so of baking soda, and simultaneously remove the stopper and turn on the garbage disposal until the water has drained. For extra help in the smell department, toss in citrus peels for a fresh scent. (Contrary to some advice, the citrus peels don’t help clean the device — nor do ice cubes.) You should avoid putting drain cleaner and other harsh chemicals in garbage disposals, which can damage both the appliance and your pipes.
Following these rules should keep your garbage disposal in tiptop shape for years. Should it get clogged or you run into other issues, consult your garbage disposal’s manual for troubleshooting before reaching out to a plumber.
Are garbage disposals environmentally friendly?
One final consideration is how much waste you should put down the garbage disposal versus in the trash, in terms of the environmental impact. (Just as a reminder, composting is the number-one choice for dealing with food waste in an environmentally friendly way, aside from reducing it to begin with.) The answer, unfortunately, is that it depends on factors such as whether your community has a sufficient supply of water and what your wastewater system does with waste.
“Whatever stuff gets separated from the water is either landfilled, condensed into fertilizer, or digested by microorganisms,” Jacob Leibenluft writes for Slate. With the last option, methane is produced that can be captured and burned as a power source. “Wastewater and environment experts agree that . . . disposals make sense if your wastewater system is set up to convert food waste into energy,” Katherine Roth writes for the Associated Press. However, only about 8 percent of wastewater treatment plants across the United States use anaerobic digesters that do this. The Water Environment Federation has an interactive map on its website that you can use to check if your local facility uses anaerobic digestion. (For Washingtonians, the Blue Plains Advanced Wastewater Treatment Plant does use anaerobic digestion.)
And for the 16 percent of households on septic tanks, there is another aspect to factor in. “Using an in-sink garbage disposal unit can impact how often you need to pump your septic tank,” the Environmental Protection Agency states. “If you must use a garbage disposal unit, your tank will need to be pumped more frequently.”