How to Relocate the Drain Field of a Septic System

Select a site for the new drain field. Consult your local plumbing codes for regulations on how far away from the house the field needs to be sited and how deep you will need to dig the pipe trenches.

Remove any shrubbery from around the new field. Dig trenches for the pipes in the final location at the required depth per the plumbing codes. These codes will vary from location to location, but generally the drainpipes need to be buried about a foot below ground.

Use a spade and pickaxe to remove any shrubbery from above the surface of the existing drain field.

Locate the drain field pipes by inserting a metal probe about a foot or so into the earth. If available, consult your drain field plan that was used during construction to help pinpoint the pipes. Once you've found the head or tail of the pipe, work your way back along the length of the pipe to find the other end. Mark the locations with stakes.

Use a sharp spade to cut the top layer of sod into parallel strips. Gently insert the spade underneath the edge of the sod and carefully separate the sod from the dirt underneath. Roll up the sod as you work your way down the pipe length or cut it into square pieces. On the house side of the pipes, uncover the pipe tees where the pipes tie together to the main septic tank.

Turn off the outlet supply at the septic tank. This will allow you to work without having to worry about sewage seeping out.

Disconnect the main pipe tee from the septic tank outlet line. Newer septic systems are typically connected with PVC pipes. These can be cut with a handsaw or rotary drilling tool. For metal pipes, loosen the coupling with a plumber's wrench then pull the pipes apart.If no coupling is present, try using a pipe wrench to loosen the pipe. If that still doesn't dislodge the pipe, use a rotary cutting tool with a metal cutting blade to cut the pipes apart.

Lift the pipes out of the drain field. If you plan on reusing the old pipes, check them for damage caused by roots or rust and replace them as needed.

Spread rocks, gravel or another material, as required by your local codes, in the bottom of the pipe trenches. Lay the pipes out in the drain field and connect them to the drain tee at the head, either by glue (PVC) or couplings (metal).

Reroute the main septic tank line to the new drain field. Either reroute the pipe or lay a new one from the septic tank to the connection tee at the head of the field.

Cover the pipes with soil and turf.

Turn the outlet valve back on at the septic tank.