The ideal depth of a septic drain field is 18 to 36 inches below the surface. The trenches must be deep enough to allow proper wastewater distribution and filtration while remaining shallow enough for oxygen to reach the soil, promoting bacterial activity that helps break down contaminants. In areas with high groundwater or poor drainage, shallower systems like mound drain fields may be required.

Yes. A metal detector is one of the quickest and easiest ways to find your septic tank. However, metal detectors can be too expensive (costing upward of $300 in some cases), and not everyone has a metal detector just lying around. If that’s the case for you, you can also take a long metal rod and poke it into the ground at regular intervals until you hit something—likely your septic tank lid.

Adding a thin layer of dirt over a septic drain field is fine, especially if soil erosion has occurred. However, adding too much dirt can compact the soil, reducing the drain field’s ability to absorb and filter wastewater properly. Avoid using heavy clay soil, as it can prevent proper drainage. Instead, use a light layer of topsoil and plant grass to help with soil stability.

A septic perc test is done by drilling a hole into the ground, filling the hole with water, and testing to see how long it drains. While simple, the test itself provides a great deal of information about your yard. The last thing you want to do is skip a perc test only to discover your yard doesn’t drain sewage effectively.