Can I Install a Garbage Disposal on a Septic Tank?

Purchasing a garbage disposal is a smart investment that will reduce your home’s waste while allowing you and other members of your family to flush leftover dinner scraps down the drain. According to a 2009 American Housing Survey conducted by the U.S. Census Bureau, nearly 1 in 2 homes in the U.S. are equipped with a functional garbage disposal. It’s an otherwise simple accessory that makes cleaning up after dinner just a little bit easier.

But homeowners connected to septic tanks instead of municipal sewer systems often wonder whether or not it’s okay to install a garbage disposal. Flushing vegetables, fruit, and other food scraps into the septic tank “may” cause it to back up, or it could adversely affect the delicate balance of bacteria that’s necessary for the natural decomposition process.

The good news is that you can still use a garbage disposal if your home is connected to a septic tank. However, you should follow some basic precautions to ensure it works and functions properly. For starters, avoid flushing fibrous material like coffee grinds, rice and pasta down the drain. These items don’t break down as quickly and may contribute to blockages in the septic tank. Place high-fiber scraps in the trash can rather than the disposal unit.

Vegetable oil, grease, lard, shortening and similar substances should also be tossed in the trash rather than poured down the garbage disposal. It’s not uncommon for these substances to harden inside the pipes or the actual septic tank. When this occurs, it can create a large mass that doesn’t break up through the normal decomposition process.

There are actually some garbage disposals designed specifically for use in homes with septic tanks. These units have built-in sprayers which hose food scraps with enzymes to assist in the decomposition process. Once the unit is turned on, the food is sprayed with enzymes as it’s flushed down the drain and into the septic tank. Opting for one of these garbage disposal units will prolong the life and improve the function of your septic tank.

You may want to have your septic tank pumped more frequently if you use a garbage disposal. The excess waste being flushed into your septic tank will cause it to fill faster than it normally would. A good rule of thumb is to hire a professional company to flush your septic tank at least once every 3 to 5 years. In doing so, you can also identify potential problems with your tank and plumbing early.