distance to leach field?

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brunolund

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is there alimony to how faraway from the tank a field can be? thinking of replacing mine, and would like to go bigger. I have lots of room, but the best spot is about 6-8 hundred feet from the tank. does that matter?
 
This would be something you would need to ask your local Department of Health & Sanitation (sometimes called Healthy and Hospitals- name varies by state) and ask about. I don't know about the line going out to the D-box for the individual field lines, but IIRC, the field lines themselves can't be longer than 100ft. If you need more than 100ft you have to split them up.

The lines also can't have more than 12" of soil on top or else the soil compaction can interfere with percolation rate. At least that is the rule where I live.

What type of field lines were you thinking of getting? Perforated pipe and gravel or Infiltrator system segments?
 
perforated pipe and gravel. it is the distance from septic tank to dbox I was wondering about
 
Looking at https://www.extension.purdue.edu/extmedia/id/id-170-w.html it says "A 2 percent slope is required from the house sewer pipe to the septic tank, while a 1 percent slope is sufficient for the pipe carrying septic effluent to the distribution box. To ensure that absorption field trenches are located in the more permeable soil horizons, the septic tank and distribution box should be installed at as shallow a depth as possible, with a minimum soil cover of at least 6 inches." That means it needs 1/8" per ft slope.

I don't know if the effluent pipe has the same rules about allowed length-- but the rule is usually that it can't exceed one pipe diameter in drop (otherwise it closes off the air and creates a vacuum so water won't flow).

If it does follow those rules, then the pipe length should not exceed 32'. (From what I read the required size of effluent pipe is 4" diameter).

Anyone know more on this? Am I correct? If not, please let me know.

But before you can put field lines anywhere, it has to be approved by your local health inspector and you will need a permit.

You will likely be asked to do a percolation test (unless the health inspector does it for you) to see how much length you need on your field lines. You will also need to check if there is a slope to the area-- it needs to be relatively flat.

Also, if your jurisdiction allows, you might want to consider getting infiltrator systems instead of pipe and gravel. It requires deeper and wider trenches, but does not require gravel, they can be shorter in length, and they can curve around. They are essentially 4' long dome segments that click together easily.

IIRC, you get charged per foot on the digging so the longer the run the more expensive it is. Depending on how long your field lines need to be, I'm not sure which method would be cheaper.

With my soil percolation rate and size of my septic tank, I would have needed 300' of perforated pipe (so three 100ft trenches). I ended up getting the Infiltrator Equalizer36 Quick4 instead so I only needed 2 shorter runs.
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TL: DR?

Probably max length from septic tank outlet to D-box is no more than 32ft (if I'm correct).
 
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the effluent is currently pumped from the tank to the field. it is pumped through 1 1/4" line approx 80' now.
 
the effluent is currently pumped from the tank to the field. it is pumped through 1 1/4" line approx 80' now.

Is your perforated pipe 1 1/4" or is the outlet pipe from the septic tank to D-box 1 1/4"?

I didn't know the pipe was allowed to be that small. Does it slope or is it level?

When you say "pumped" do you mean that you have a mechanical system that pumps it out?
 
yes. my system has a pump that draws out of the septic tank, and pumps it out to the field through the 1 1/4" poly pipe. then it goes into the dbox and out to the drain lines in gravel. my field is too small I believe, and older. it started leaking a bit last year.
 
yes. my system has a pump that draws out of the septic tank, and pumps it out to the field through the 1 1/4" poly pipe. then it goes into the dbox and out to the drain lines in gravel. my field is too small I believe, and older. it started leaking a bit last year.

Ah. I may have been wrong about the length of the pipe because I realized that was for trap arms. I don't think there is a limit on length of pipes after a vent.

I'm only somewhat familiar with non-mechanical systems. Since you have a pump that actively pushes water out, then I'm guessing there probably should not be a limit on the length so long as the leach field will still remain on your property and will still be within the limits. I think it might not even have to slope if it is pumped out.

Do you have an aerobic effluent treatment system then? (3 tanks or chambers: inlet, aerobic treatment, and pump)?

Is the water essentially cleaned or treated before being pumped?

Sorry if I'm not any help.

Anyone who knows about mechanical systems around?
 
it goes into atwo chamber septic tank, then is pumped out of the liquid side and out to the field.
 
Ok. I wish I knew more about mechanical systems. I'm afraid I can't be of any help.

Before you get anything done though, you would legally have to contact your local department of health. Mine gave me a pamphlet about septic tanks and leach fields and answered a few questions. The inspector should be able to answer your questions on any length limitations. Even if you don't set up an appointment, sometimes you can call and ask. Some places have e-mail for their health inspectors (mine doesn't) so you can try e-mailing or calling to ask questions.
 

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