Septic Main Sewer Line

[Pettrix]

My calculator says 3.75 inches
.25 for 10 feet
150 feet = 15 10 sections
So 15*.25 = 3.75納/QUOTE]


I swapped inches for feet so my 3.75 was feet, not inches, but you are correct. It's 3.75 inches

 

[bnold]

1/8” per foot is typical for plumbing

150’x1/8” per foot = 18.75” fall

1% is typical for site sewer lines...
1% @ 150’ = 1.5’ or 18” fall

 

[PILOON]

Re slopes:
You also don't want too steep a slope as the sewage will rush downhill and pile up to create a jamb.
Another precaution is to make clean cuts when joining fittings and even de burring the inside edges.
I like a chopsaw for perfect cuts.
As to de burring, I've seen burrs and rough cuts catch and trap J cloths rags etc that occasionally find their way in there.

 

[MossRoad]

Don't forget about putting in enough cleanouts on long lines either. Snakes are only so long.

 

[riptides]

Don't forget about putting in enough cleanouts on long lines either. Snakes are only so long.

Good one.

 

[4570Man]

Don't forget about putting in enough cleanouts on long lines either. Snakes are only so long.

I’m not sure what the distance is but it’s code to have clean outs in it at that distance.

 

[MossRoad]

It's also a good idea to have a cleanout directly outside the house regardless of distance to the septic tank, street hookup, etc... it keeps the goop outside of the house if there's a need to use it.

 

[4570Man]

It's also a good idea to have a cleanout directly outside the house regardless of distance to the septic tank, street hookup, etc... it keeps the goop outside of the house if there's a need to use it.

I never do. It’s code to have one within 10’ of where the line exists the house on the inside and I usually put the tank within 10’ of the structure so 20’ max distance. My experience is the #1 clog location is the baffle at the pipe exit inside the tank.

 

[MossRoad]

I never do. It’s code to have one within 10’ of where the line exists the house on the inside and I usually put the tank within 10’ of the structure so 20’ max distance. My experience is the #1 clog location is the baffle at the pipe exit inside the tank.

Yes, however, we're talking about long runs in this thread, not 10' from the structure. Regardless, I'd rather have a plumber snake a pipe from outside my house than in my basement.

 

[Ford850]

Main septic lines are usually required to have 1/8” - 1/4” fall per foot, not 10’.
1/8” - 1/4” fall per 10’ is usually for drainage tile (water).