Septic System Baffles

RCI Septic Service • January 26, 2023

Baffles are an important part of the septic system. They are placed at the inlet and outlet pipes on the tank, this help process your wastewater on a daily basis. Baffles in older tanks are made of concrete which can deteriorate and crumble after time, baffles in newer tanks are made of plastic such as SDR-35 or SCH40 pipe and are much more durable.


The inlet baffle is situated at the junction between the tank and main sewer line leading from the house. It’s designed to assist wastewater to flow smoothly into the tank guiding it down so it comes up on the outside top of the tank. The top of the T-baffle allows airflow and it also protects solids from blocking the inlet pipe.


The outlet baffle keeps the solids and bacteria from exiting the tank and entering the leach field system which could possibly cause failure over time. The outlet baffle on some newer tanks, Enviro systems or Elgen systems, may have an effluent filter to further prevent solids from exiting the tank. We recommend this filter be rinsed every 6 months so that it doesn’t plug up and cause a back-up into the home.


When we pump your tank, we always do a visual inspection of the baffles to assure they are functioning properly and clean the filter if there is one. 

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