Cesspools and Seepage Pits

Cesspools

The cesspool is the forerunner to the modern septic system. The cesspool is simply a vertical pit dug into the earth. The pit is lined with a porous cement, or block, or stone. The area outside the liner is filled with gravel. All the wastewater from the home is routed 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 far from 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. Avoid putting grease and food down the drains. See the septic system care page on this web site.

Seepage Pits

Although many people confuse cesspools with seepage pits and Vic versa, they serve different purposes in treating wastewater. A seepage pit is similar to a cesspool in construction consisting 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, 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. Because of their construction seepage pits are not as efficient at processing effluent as drainfields or soil absorption beds.