Can You Use a Garbage Disposer with a Septic Tank?

Home > Kitchen > Garbage Disposers | Last updated August 28th, 2019

Best overall

Photo of InSinkErator Evolution Septic Assist

InSinkErator Evolution Septic Assist

Best on a budget

Photo of Waste King L-8000 Waste Disposal

Waste King L-8000

Septic Tank Safe Garbage Disposal Guide (2019)

Almost 1/5 of homes in the USA are connected to a septic tank system with rural homes the least likely to be connected to a public sewer system. Many of these homeowners are confused about the conflicting advice on whether garbage disposals are bad for septic tanks. Hopefully this article will answer the question and help you decide whether a garbage disposer is right for your household.

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Best disposer for septic tanks reccommendation badge

The best overall garbage disposer for septic tank systems

InSinkErator Evolution Septic Assist

Photo of InSinkErator Evolution Septic Assist

Features:

  • 3/4 HP Motor
  • Stainless Steel
  • Continuous Feed
  • 4-Year Warranty

Septic tank safe:

  • Bio-charge enzymes breaks down food waste

This Evolution with Septic Assist has been designed to use safely with a septic system. Its Biocharge injection system breaks down food particles even further to prevent blockages.

Best disposer on a budget badge for septic tanks

The best budget garbage disposer for septic tank systems

Waste King L-8000

Photo of septic tank safe Waste King L-8000 Waste Disposal

Features:

  • 1HP Motor
  • Stainless Steel
  • Continuous Feed
  • Limited Lifetime Warranty

Septic tank safe:

  • Powerful Motor Breaks Down Food Waste

The high-powered L-8000 uses a 1HP motor to efficiently break down food waste particles. The Waste King is a great qualty, septic-safe waste disposer & perfect for households on a budget.

Septic tanks are very sensitive to what you flush into your waste water and some food waste items are not suitable.

Are garbage disposals safe for septic tanks?

The simple answer to “can I have a garbage disposal with a septic tank?” is yes! However, before you go out and buy a waste disposer there are a few things that you need to be aware of. Fitting the wrong garbage disposer can put a strain on your septic system so make sure you read this page and the waste disposal buying guide before making a purchase.

Many septic tank owners opt to install a waste disposal unit without problems or additional septic tank pumping. However, it’s good to remember that septic tanks are much more sensitive to what you flush into your waste water and that some food waste items are not suitable and will cause problems. If you treat your garbage disposer like a bin then you will end up causing problems in the future. Some food waste will not be broken down by your septic tank and some items like rice and pasta will even expand when the enter the system causing blockages.

Remember not to use your waste disposal unit like a trash can. Some types of food waste will struggle to break down in your septic tank and will eventually accumulate.

Things to consider

What can you put down a garbage disposal with a septic tank?

Small food scraps that end up in your sink are fine to put through the garbage disposer as they will be broken down efficiently by the grinding chamber. Once in the septic tank they will be further broken down by your tank’s bacteria.

  • Small food scraps
  • Dishwasher outlet

Connecting your dishwasher outlet to your waste disposer is an effective way of ensuring any food scraps that flow from your dishwasher are broken down.

What not to put in a garbage disposal with a septic tank

Remember not to use your waste disposal unit like a trash can. Some types of food waste will struggle to break down in your septic tank and will eventually accumulate causing blockages requiring more regular pumping. Putting too much organic matter into your septic tank will also alter the finely tuned bacteria levels in your tank making it less effective at treating your waste water.

  • Cooking oils, fat, grease
    A septic tank will be unable to break these down effectively causing them to solidify and float to the surface of the tank causing problems.
  • Non-food items
    These will not be broken down effectively and will alter your tanks bacteria levels.
  • Fibrous vegetables
    Low-end garbage disposers struggle to grind down stringy/fibrous foods like celery causing them to accumulate and block your septic system.

The bacterial culture inside a septic tank is finely balanced and a critical part of the waste water treatment process.

Garbage disposals & septic tank bacteria

One of the main arguments of whether garbage disposers are safe to use with septic tanks is the bacteria problem. The bacterial culture inside a septic tank is finely balanced and a critical part of the waste water treatment process. Overloading a septic tank with too much organic matter can disrupt the delicate bacteria levels causing food waste to accumulate and eventually block the tank requiring regular pumping and repairs to your septic system.

One way to overcome this is by using special enzyme additives. Usually this requires you to add them directly into the septic tank. Some garbage disposal manufacturers like InSinkErator have a unique solution to this by injecting the enzymes directly into your septic tank every time food waste passes through the disposer.

If you are worried about your waste disposal unit harming the bacteria levels check out the recommended garbage disposers for septic tanks.