Cesspools and Seepage Pits

Cesspools and seepage pits

Cesspools and Seepage Pits

Cesspools and seepage pits are the predecessors of the modern day septic system.  Older houses may still be utilizing these systems especially if they have not been sold in the last 100 years.  So what is a cesspool and seepage pit?


The cesspool is the forerunner to the modern day septic system. The cesspool is simply a vertical pit dug into the earth. This pit is lined with a porous cement, or block, or stone. Gravel fills the area outside of the liner.   Wastewater from the home is channeled to the cesspool. The solids fall to the bottom where they are partially digested by bacteria and microorganisms that occur there naturally. The effluent leaches out into the gravel and soil surrounding the pit.

Today, cesspools are not the best method of dealing with household wastewater. If your home has one and it is working properly, keep it carefully maintained by having it pumped regularly. Avoiding putting grease and food down the drains will help keep it working properly.

Seepage Pits

Many people confuse cesspools with seepage pits. They serve different purposes in treating wastewater. A seepage pit is similar to a cesspool in construction. It  consists of a large pit lined with concrete rings, or porous masonry block to support the walls of the pit, and a surrounding bed of gravel. The difference is that only effluent that has come from a septic tank enters a seepage pit. The effluent has already been through the first stage of processing in the tank. Once it enters the seepage pit it is temporarily stored there until it gradually seeps through the walls and into the surrounding soil. A biomat forms in the bottom of the pit and as the pit ages the biomat grows thick clogging the pores of the pit walls. Seepage pits are not as efficient at processing effluent as drainfields or soil absorption beds.

The most serious concern with both cesspools and seepage pits involves the water table.  They are both closer to the water table, and therefore, they do not protect our groundwater as well as a modern septic system.


All Clear Septic can answer all your septic questions and help you maintain the system you utilize.  Call 508-763-4431 or visit www.allclearseptic.com and ask the experts.   Whatever town you reside in, whether Middleboro, MA or Portsmouth, RI, etc. we can answer all your questions.

This blog was posted on www.allclearseptic.com on February 24, 2016.

0 replies

Leave a Reply

Want to join the discussion?
Feel free to contribute!

Leave a Reply