Septic System Distribution Box

The septic system distribution box is a critical part of your system’s operation. Its job is to route effluent from the septic tank to the drain field. If a distribution box becomes faulty, the septic effluent will be routed to only a portion of the drain field. This situation could lead to overload of the field which is often characterized by lush green growth, wet or soggy earth and/or the tell tale smell of sewage.

As you can see in the accompanying pictures, after many years of use, there is a very strong possibility of a sludge build up. This occurs when solids are able to exit the septic tank. Tanks must be pumped out every five years by qualified septic contractors. Tree roots also enter the distribution box and clog drain field lines, as evidenced in these pictures as well.

The D-Boxes originally installed in the community were composed of concrete. Concrete boxes typically last 20 years. As a result of sludge buildup, invasion of theD-Box by tree roots, failure to have the septic tank drained, etc, some neighbors have had to replace old D-Boxes. The costs to do so run roughly between $1200 and $3500. Most of the new boxes being installed are plastic and are not susceptible to the deterioration associated with the concrete type.

The installation and backfill during the replacement of the plastic boxes is critical. Any repair or replacement of distribution boxes must be done with a permit issued by the Fairfax County Health Department and by a contractor that is licensed by the Health Department.

The Health Department must also inspect any repair/replacement prior to the backfill of the boxes. If you have questions about replacement of your Distribution Box or any matters relating to your septic system you can call the county at 703-246-2201. The County can also provide a list ofcontractors per your request.

Corroded Outlet PipeSludge Build UpTree Roots


Septic Systems ExplainedSeptic Systems Maintenance