Not sure where your septic tank is buried? Here are five reliable ways to find it.
Most counties require septic permits and keep records of system locations, including a site map. Contact your county health department and request the septic permit file for your property. This is the most reliable starting point and often free.
Your septic tank is connected to your home's main drain line. Locate where the main drain exits the house (usually through the foundation), then probe the soil in a straight line 10–25 feet from that exit point.
A soil probe pushed into the soil will find the hard surface of the tank lid. Probe systematically in a grid pattern once you've identified the probable area. You'll feel resistance change when you hit concrete or fiberglass.
Look for slight depressions, mounds, or differences in grass color in a line from your house. Older tanks sometimes cause uneven settling. Plastic or concrete access risers may be visible at or near grade on newer installations.
Septic locating services use electronic transmitters inserted into drain lines to pinpoint tank location precisely. Many pump-out companies offer this for $50–$100. Worth it if other methods fail.
Once located, mark the tank and drain field on a property sketch and keep it with your home records. Install risers if the lid is buried deep to prevent future excavation.
Use our free calculator to get the right tank size for your home in under 2 minutes.
Use the Free Calculator →Most residential septic tanks are 10–25 feet from the house, connected by the main drain line. The drain field is further out — typically 20–100 feet beyond the tank.
Yes — a plumber can run a camera down your drain line and use a locator to trace the pipe to the tank. Septic pumping companies also offer locating services.
Probing with a metal rod is safe and won't damage a properly installed tank. Hand digging once you've located the lid area is also fine. Do not use powered equipment over the tank or drain field.
Older homes may predate county septic records. Use the drain pipe method, use a probe, or hire an electronic locating service. A local pump company may also have knowledge of common tank placements in older neighborhoods.