Septic tanks and holding tanks. Homeowners commonly intertwine these two terms, but wrongfully so! A septic tank and a holding tank are two very different things!


A septic tank is your first level of treatment in a typical septic system. A septic tank collects sewage and wastewater that flows from the house and separates the solids from the liquids. Light solids float to the top and heavy solids sink to the bottom. This leaves a clearer layer of water in the middle. This clearer layer, called effluent, exits the septic tank through the outlet pipe and leads into the drainfield, where it disperses into the soil and “disappears”.

THE KEY THING to remember here is that a septic tank has an outlet pipe!


A se holding tank collects household wastewater and stores it for removal. There is no outlet pipe in a holding tank! Wastewater that enters a holding tank remains there until it is pumped out.

THE KEY THING to remember here is that a holding tank does not have an outlet pipe.



Both septic tanks and holding tanks need pumped every so often. However, there is a great deal of difference in the frequency of pumpings between these two tanks.


septic tank needs pumped every one to three years (depending on some varying factors, found here). The reason you pump a septic tank is to remove the solids that build up in the tank over time. If you don’t remove these solids regularly, they will build up and fail the system. The whole septic tank is emptied to make room for more solids to collect again. REMEMBER, the liquids are not of concern here. They can flow freely out of the septic tank into the drainfield.

REMEMBER septic tanks need pumped every one to three years in order to remove built-up solids.


holding tank needs pumped every few weeks or monthly. Depending on the size of the holding tank and the amount of water being used, frequent pumping is needed to empty them because solids and water build up in the tank. There is no drainfield attached to a holding tank. Every drop of water put down the drain in the house collects in the tank. The only way to remove wastewater from a holding tank is to pump it. Holding tanks are sized to hold a few-weeks-to-a-month’s worth of wastewater, based on average water-usage statistics. With normal usage, a holding tank will fill up within that time range and need emptied.

REMEMBER holding tanks needs pumped every few weeks or monthly in order to remove everything.