Strong overlap with existing septic management. Verify lid access before building over it.
A new shed pad is being framed, a patio is being laid, a deck is extending into the yard, or a heavy gravel driveway is being poured.
The septic tank access lids, the pump chamber, the distribution box (D-box), or the delicate drainfield/leach field.
County health department septic as-built diagrams. Look for green plastic lids flush with the grass, or slightly depressed areas of the yard. Check pump records from the last time the system was serviced.
Many older septic tanks do not have risers brought to the surface. A perfectly flat, unmarked patch of grass could be sitting exactly 12 inches above a 1,000-gallon concrete tank lid.
Building a permanent shed or deck over a septic lid makes mandatory pumping impossible. You will have to crane the shed away, tear down the deck, or abandon the tank and install a new system. Driving heavy equipment over a drainfield can crush it, resulting in a full system replacement costing tens of thousands.
Any time a structure is being built in the backyard of a home on a septic system, or heavy machinery will traverse the yard. Exact locations must be marked.
Contact a Septic Contractor to locate and flag the system before you cover.
Call 877-735-2796 to connect with local specialists
Building over your septic? If you're specifically trying to locate your septic tank before a backyard project, this step-by-step guide walks you through finding lids, reading as-built diagrams, and knowing exactly what to mark before the heavy equipment arrives.