If your septic system was installed after the late 1980s, chances are it is a two-compartment tank that uses a dividing wall. The wall traps most of the paper and waste in the first compartment of your septic tank, keeping the sludge level lighter in the second compartment where the liquids exit the tank toward the drainfield.
More and more we are seeing these dividing walls detaching from septic tanks and leaning one way or the other inside the tanks, especially when the wall is made of plastic (most walls are made of concrete and are very sturdy, although we see those detach too).
A leaning or fallen dividing wall can cause two main issues.
The first is that your septic system begins functioning as a single-compartment tank (instead of using two compartments). This does not devastate the system, but it can make cleaning the tank more difficult — if the wall falls flat on the floor of the septic tank, any solids trapped underneath cannot be removed, forcing you to pump the tank more frequently.
The second issue occurs when the dividing wall falls towards the outlet side of the tank. Sometimes this fall breaks off the outlet baffle, allowing scum to flow freely out to the drainfield and causing premature drainfield failure. Once your drainfield is clogged up with sludge, it’s likely you would need to install a new drainfield or a whole new system.
Re-attaching a leaning or fallen dividing wall is not an option. In most cases a fallen wall means replacing the entire septic tank — and due to changes in septic regulations getting a new septic tank may require getting a totally new septic system.
The best way to prevent a falling dividing wall is to pump out your septic tank every 3-5 years, especially if the wall in your tank is made of plastic.
Routine pumpings prevent heavy sludge from building up and pushing over an improperly-secured dividing wall.
We pumped our first septic tank over 75 years ago, so there’s not much we haven’t seen. Call us at 210.698.2000 (San Antonio) or 830.249.4000 (Boerne) or contact us online to schedule a septic pumping.