There are two options for sending the effluent from a septic tank to
the leach field. Old style septic tanks are piped so the effulent flows
to all the pipes of the leach field, and no D-box (diverter box) is
In a parallel system, an attempt is made to send equal amounts of wastewater to each pipe of the drainfield. There may be an accessible gate / valve that the homeowner is supposed to change annually, so select a different pipe as the primary recipient.
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