Ongoing Stoppages

[gjunkie]

I purchased my first home in September. We did not have any issues at first, but for the past month or so the main line has been getting clogged regularly (the drain cleaner is on his way out for the third time, and I have managed to clear the line myself a couple of times (hose/hand snake).

The drain cleaner thinks we are going to have continual problems unless we make a change. I tend to agree -- the existing layout makes no sense (The septic tank was moved a couple years ago -- it used to be under the large deck. At that time they obviously simply extended the line around the deck to the new septic). The slope is minimal everywhere in the system.

Here's the existing layout:


And here is my first draft of my new layout:


This should not be TOO much work to do: Worst part will be removing a section of the deck. The ground is very diggable fortunately. All of the plumbing under the house is exposed -- the pipe goes underground at around the edge of the deck.

So.. am I on the right track? What should I be considering before I jump in and start digging?

Happy Monday

Chris

 

[hj]

It looks good, and since you are not changing anything at the terminals, and assuming they are already done correctly, you should not have any problems.

 

[Sponsor]

 

[Jadnashua]

By shortening the run and eliminating some bends, you should end up with a bit more slope, so that may help as well. Try to maintain at least 1/4" per foot slope in any one of the lines and ensure there are no dips or humps. The 4" technically can work with less pitch, but the smaller lines can't.

 

[gjunkie]

So it finally stopped raining, and I started digging. Good times. I feel pretty comfortable about this project, except for the actual connection of the new pipe to the septic tank. Looks like the existing pipe is mortared into place. Do I simply need to chip that mortar out and re-mortar my new pipe in place? Am I taking a big risk by chipping out the mortar (e.g. do I risk damaging the tank)? Is there another material I should use? The approx direction at which the new pipe will enter is shown. There is MAYBE just barely enough space to attach a (45?) bend to the existing pipe, but I would rather have it enter directly into the tank, rather than joining to the existing pipe somehow (the whole point of this is to make the path as efficient as possible, since the slope is minimal)

TIA for you comments and suggestions.

 

[MACPLUMB]

Yes you can chip that fitting out, and redo like you posted but you need the pipe going straight into the side wall of the tank because you need to install a baffle tee inside the tank,
this is just a standard San tee installed in the vertical plane open on the top and the bottom !
This must be there even if you have to have tank pumped to do it right !
A plumber would use hydraulic cement to patch around the new pipe !

 

[gjunkie]

Thanks for the info. The exsting pipe is nowhere near perpendicular to the tank.. I don;t recall seeing a tee like what you describe when the tank was inspected (but my memory is terrible). I will take the lid off tomorrow and take better photos.

what is the purpose of the baffle tee?

 

[MACPLUMB]

IT IS TO STOP THE INFLOW RUSH OF WATER FROM DISTURBING THE BIOMASS THAT FLOATS ON TOP,

THIS IS WHERE THE MOST IMPORTANT PART OF THE SEPTIC TANK WORKS !

BACTERIA DISSOLVING THE WASTES INTO LIQUID !

WHERE YOU BRAKE THIS UP IT SLOWS DOWN THE PROCESS !

ALSO SINCE YOU HAVE TANK DUG UP AND EXPOSED IT IS ALSO A GOOD IDEAL TO ADD A POST FILTER ON


THE OUTLET TO THE DRAIN FIELD !

http://www.thenaturalhome.com/septic.html

SCROLL DOWN ON PAGE TO SEE THE OUTLET FILTER

 

[hj]

The "baffle" probably constructed as part of that tank, rather than a sanitary tee. IF it is a sanitary tee, which is not likely unless the pipe out of the tank is 4" I.D. S&D pipe which would then need an adapter bushing to connect to standard pipe, then remove the concrete, cut the pipe, and rotate it square with the tank.

 

[gjunkie]

I opened the tank, and there is indeed a "sani-tee" baffle on the end of the pipe. I noticed that the incoming pipe is 3in, not 4in as I had previously thought. I have attached updated before and after diagrams, and an image of the existing baffle in the tank.

So, questions:

1. Is it normal to use 3in pipe coming into the septic? I would have expected 4in, and I was planning to use 4in.

2. The existing pipe does not enter the tank at a 90 degree angle, and the new pipe will not either (unless I include a bend). I am not totally clear on whether this is OK. Intuition tells me that it is better to have as few bends as possible, but perhaps there is a good reason for having the pipe (baffle) terminate in the exact center of the tank (thus requiring that the pipe be exactly perpendicular to the tank).

 

[MACPLUMB]

Follow your red line with 4" abs,
they used 3" before for whatever reason but you can go back with 4" and a tee baffle

 

[gjunkie]

It's more fun doodling on the computer than crawling under the house. So, well, here I am. It turns out that I have more vertical "room" to deal with than I was expecting. So instead of a constant shallow slope from fixture to septic, I am going to have something more like the attached.

My main question is about the run from B. It will be 1/4in per foot to where it meets the line from the septic. There, my plan is to use a 45 connected to a long-bend 90 (set at 45 degrees). Is this the right way to go?

 

[Chefwong]

OT: GJUNKIE...
what program are you using to doodle with.
Love it...looks like I could similar to keep track on how my proposed electrical runs will be...

 

[gjunkie]

Adobe Illustrator. Far from the optimum tool, but it's what I have (story of my life LOL)

 

[Chefwong]

AI-- way outta my league.
Closest thing is MS Visio (project manager) where I can grab icons and ~snap~ ressize, etc