Garbage Disposals & Septic Systems

Garbage Disposals & Septic Systems: What is your take on using a garbage disposal when the sewage system for the home is a septic tank with a drain field? Do you know there are items that should never be devoured in a disposal on a septic system? 

Many contractors will argue with me but I learned many years ago from a Caldwell county soil scientist that one should NEVER use a garbage disposal on a septic system. But it does depend on the location of the baffle wall opening in the tank. The septic tank works because the waste that flows into the 2-sided tank sinks to the bottom of the first tank to be eaten by bacteria. The foods from the disposal don't sink. When the baffle is close to the top of the wall, these miniscule particles float on top of the wastewater over the baffle wall straight into the T that serves the field. It is this T that clogs and won't allow the wastewater to get to the drain field. The tank overflows and that is a mess. On newer tanks, the baffle is located in the middle of the baffle wall, to keep the floating foods out of the T. But, still some foods expand between the disposal and the tank and clog the inlet baffle. If the system has 2 tanks, as in a pump tank when the wastewater is pumped up to the field, then the system has a better chance of not clogging.

   

Here's a list of what to NOT put in a disposal on a septic system: celery, asparagus and corn husks; coffee grounds, egg shells and potato skins; bones, seeds and pits; oil, fat and grease; beans, rice and pasta; cigarette butts, rubber bands, bread ties, pull tabs, sponges, wipes. The non-organic items are not capable of breaking down, so they will either get stuck in the lines or stay trapped inside the septic tank.

For all the skinny on all the DOs & DONTs of disposals & septic systems, check out the Advanced Septic Services website.