As the owner of a custom home, you can be sure that the builder and landscaper didn’t build anything like a patio over your septic tank, right? Unfortunately this exact situation is more common than you think.
As part of preparation for our septic inspections, we obtain a copy of the septic records (which usually includes a drawing of the system location) and compare that with online pictures of the house (through the listing service and aerial map views).
In many cases, we can spot a problem before we visit the site. Which is exactly what happened in this case. Based on my research before we visited the property, I suspected the tank was located under a flagstone patio.
When I inquired about the tank location with the homeowner, they were appalled that such a thing would even be possible. After all, they had the utmost regard for the landscaper who had designed and built the patio.
Unfortunately, my suspicion was correct; this home’s tank had two compartments and two lids. One was located just outside the flagstone, so we were able to expose it and pump that side of the tank.
However, the other lid was under the flagstone. This prevented us from pumping the tank and inspecting the system thoroughly.
This two compartment scenario is widely unknown to homeowners; often we find they thought they were being careful not to build over the access lid, but didn’t realize there is a second lid on their septic tank.