Many septic system owners want to know when their tank is full so they know when to schedule a pumping. The problem is there are multiple definitions of a “full” septic tank, and only one way — opening the tank lids — to confirm it. Just because a septic system appears to be functioning properly, doesn’t mean it’s not full and in need of a pumping.
There are three ways your septic tank may be considered “full.”
At this level, the tank’s outlet pipe allows liquids to flow in your septic system’s absorption area. The water level falls when the septic tank is pumped, but fills back to this normal level as the system is used.
As the tank reaches its normal fill level and the system continues being used, toilet paper and waste accumulate and get “trapped” in the tank (liquids continue flowing out of the outlet pipe to the absorption area).
Some of this paper and solid waste breaks down, but it cannot all magically disappear by itself — the septic tank must be routinely pumped and this sludge removed (most septic tanks should be pumped every 3-5 years).
A septic tank is considered “overfull” when the water level is at the very top of the tank. If the septic system’s absorption field stops accepting the water, it sits in the outflow pipe and backs up, overfilling the tank.
No matter how long it’s been since you last pumped your septic tank, it’s “full” to a certain degree. But if it’s been 3-5 years since you last had it pumped, it’s probably time to do so.
Don’t wait until you have a problem to pump out your tank — by then, it’s usually too late to solve anything. Waiting too long between pumpings allows the sludge to continue accumulating, and can cause damage to your drainfield.
Van Delden Wastewater Systems has been installing and maintaining septic systems in the Texas Hill Country since 1937. Give us a call at 830.249.4000 (Boerne) or 210.698.2000 (San Antonio) to schedule a septic pumping.