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Septic Tank Garbage Disposal

How many homes in the United States do you think rely on a septic system for their household sanitation needs? 5 million you guess? Go higher. 15 million, maybe? Still higher. Try 27 million homes. If we say that there are an average of 3 people in each house that is nearly 81 million people!

Recent studies indicate that of these 27 million homes, only 22 percent have elected to install a garbage disposal. The 78 percent who do not have garbage disposals choose not to do it largely because they feel these devices will harm their septic tanks or drain fields.

The truth of the matter - as stated by the Federal Housing Authority and other key industry groups such as the Small Flows Clearing House - is that garbage disposals work just fine when coupled with a septic system that has been sized correctly and is maintained on a regular basis.


When you send solid particles into a 1,500 gallon capacity septic tank, they begin to accumulate. This accumulation is called sludge. Waste particles that can be broken down by the bacteria within a septic tank can sometimes become sludge if the bacteria doesn't have a chance to attack it.

One of the reasons this can happen is that the particles do not remain in suspension for a long enough period of time. When this happens, the bacteria that break down waste simply do not have enough time to "eat" the waste. As sludge begins to build in a septic tank, it effectively reduces the capacity of the tank and beneficial bacteria.

In our case, let's say that 400 gallons of sludge is in the bottom of the tank. This means we only have 1,100 gallons of bacteria filled water left to attack food and other waste particles. Is it starting to become clear why regular tank maintenance is important? For the same reason, you should avoid sending solid objects such as cat litter, plastic Star Wars figures, and other objects towards the septic tank.


You can purchase countless septic tank and system additives. Some of these products are harmful to the biological activity within the septic system. In fact, some additives can rapidly kill the bacteria within the tank. If this happens you will quickly ruin your entire system as solid particles of waste will be carried to the drainfield. When this happens, it is curtains. The solid particles clog the gravel and soil that surrounds the perforated drain pipe in the leachfield. Clogged gravel and soil means the polluted water has nowhere to go but the surface or it can travel through the soil to contaminate other groundwater resources.

Related Articles:   Septic Tank MaintenanceGarbage Disposal for Septic Tank ManufacturerSafe Septic Tank AdditivesDisposals Harm Septic Systems - Garbage!

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3 Responses to Septic Tank Garbage Disposal

  1. Tim I've read a bunch of your articles on home repairs and find them to be helpful and informative, for the most part. I have to disagree with you on this one for the reasons you state in the displacement part of your article. Use of a garbage disposal that is not made for septic systems with a septic system places more sludge and creates less anarobic bacteria to digest this sludge so it accumulates in the tank making the need to have it serviced sooner a greater likely hood, It also contributes to failure of the system because of non digested solids clogging the drain fields. Just my opinion as a Master Licensed Plumber for over 30 years and still working at a trade I enjoy.

    • John,

      There's two schools of thought on this. One says keep as much food out of the tank as possible. Another says a healthy tank can digest and break down the waste. The disposer grinds up the waste creating far more surface area making breakdown easy. If you REALLY want to enhance the bacteria in the tank to help them, you add one-half cup of Certified organic oxygen bleach each week to the tank. Things break down faster in the presence of oxygen. Septic tanks are devoid of oxygen because the methane gas production forces it out of the tank.

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