Install a septic tank riser system by exposing the top of the tank, installing the adapter ring and risers, and adding the new lid. A riser system eliminates the need to dig to expose the lids each time the tank requires service.
The first step in installing a riser system involves a final dig to expose the top of the tank. If you do not know the location of the tank, contact the local building department for a drawing that shows its location. Single compartment tanks generally have a single central lid, while dual chamber tanks have a lid for each compartment. Each large lid requires a riser. The height of the riser depends on the depth of the tank and on whether you prefer exposing the lids to eliminate all digging or burying them just below the surface of the ground to camouflage them.
Remove the existing tank lids and install the adapter ring on the tank with concrete. Once the concrete is dry, add as many risers as the system requires to bring the new lids to the correct height. Use the manufacturer’s recommendation to connect risers for a watertight seal. Place the new lids on the risers, and backfill the hole around the risers with soil. For buried risers, place sod on top of the soil.