Sarratt Septic

What is a distribution box?

A distribution box is also known as a d-box.

It splits the liquid flow from the septic tank into two or more leachfield lines.

D-boxes are notoriously finicky.

When a d-box is out of level by as little as a 1/16 of an inch, liquid tends to

 flow down one line of the drainfield over the others.

Overtime this causes premature failure of the leachfield line.

A shovel full of dirt can easily thrown a d-box out of level.

D-boxes are a known problem in the industry.

The standard solution is to use levelers (a.k.a. speed levelers).

But these are not a magic bullet. Levelers just help some.

I recommend:

Besides a shovel full of dirt, what really causes a d-box to be out of level is a

little frost heave.

Over a few years time they will shift ¼ or even ½ inch out of level.

Go ahead and get in the habit of adjusting your d-box every year in the


The best way to prevent frost heave is to do what they do under railroad

 tracks, place the d-box on a nice thick (1.5' at least) bed of gravel that goes

below the frost depth.

What is the frost depth? It varies throughout the State.

In the mountains it is about 1' so you do 1.5' of gravel unless you are above

4000 feet then go ahead and do 2' of gravel. On the coast it is probably 6” so

go ahead and do 1'.

Use clean washed gravel compacted in 3 or 6” lifts.

Use the more expensive levelers—they work better.

Ideally, use a tipping-style distribution box--I manufacture these or a flout--I

install these.

My Tipping Distribution Box Story>

Sarratt Septic

Ph 828-447-5184