I do not know what's happening. AFAICT these white PVC caps are cleanouts for the sewer line. (Although one guy who looked at them thought they were cleanouts for the gutter/drainage system--you can see the gutter coming down in the one photo.) All I know is the PVC cap nearest the 4X4 came off/was ajar one day about a month ago, and some soggy white tissue-like stuff and some brown coloring (that may have been feces, but not like chunks or anything) had been splattered in about a 3 ft radius. A friend said get a cap. I did. This one in particular.


I installed it in the PVC cap that had come off. It fit great. I thought the problem was solved.



A friend thought the vent stack on the roof might be clogged but it (if that is indeed the vent stack. It's in the area of the PVC caps but on the other side of the roof) looked okay to me.


Today, the other cap was ajar (you can see who the ground shifted, that was where the cap was leaning). And this time, the radius of the tissues, etc. was about a 10 ft radius but I was surprised it did not hit the building. I circled the area of the splattering on the below photo.


Here are some closeup photos.




So the obvious solution, to my unprofessional mind anyway, was to cap the other PVC cap (there is a 4 inch PVC pipe about 6 inches below ground level), but the friend also sent me this diagram:

And the highlighted text really concerned me. I thought, "What if I plug the remaining cap, and the pressure builds and bursts a pipe on the inside (or something worse)?"

I say that because, again in my unprofessional opinion, it seemed like pressure pushed the PVC caps off. (But the PVC caps were not attached by a coupler or firmly affixed to the PVC pipes below by anything other than the asphalt surrounding them.)

One last observation. I've been living here 12 years and never once had a problem with either PVC cap. A friend speculated that perhaps the city (they tore up the street in front of the building and put in new storm sewers) doing the construction somehow caused the PVC caps to come off and spew the tissue-like stuff etc.

So, get another PVC test plug (like in the photo) and install it in the PVC pipe beneath the white PVC cap that overflowed/spewed recently? Call the Public Works dept? A plumber? Something else?

Thank you.

 

I am confused. Why did you post a picture of a test cap but then photos of threaded caps being used. Then you mention test caps again? You have a picture of two capped pipes then say you are going to cap "the other" cap???

If you have caps in place and are getting poo juice and toilet paper on the driveway the pipe is probably broken underground. Possibly someone drove over it.

 

Too many large pictures create a slow loading thread.

You've got a problem there that may be out of your control.
You're experiencing problems between your house and the city sewer system.
That says to me your city has some sewer issues.
There should not be pressure between your house and city sewer system.

If you had a vent problem you'd have smells inside the house as well as extremely slow draining issues and likely overflow of lower connected units.

You may just have a clog between your house and the city sewer system. The force from flushing on the second floor could cause high pressure at those cleanouts. Those clean out fittings are supposed to be glued to the pipe and the covers screw in. If they had been installed properly you would definitely have had overflows inside the house.

You could certainly check with Public Works on a system issue. Typically if there is a problem on the street it affects more homes. See if your neighbors are having problems. If no.... probably time to call a plumber and start by snaking or checking with a camera.... the line to the street.

 

Pilot Dane Sorry for the confusion. My bad. The white PVC cap nearest the 4X4 emitted the discharge a couple of weeks ago. So I removed that white PVC cap and installed the Sioux Chief plug securely. (So beneath that white cap nearest the 4X4 is the Sioux Chief plug.) It was only recently that the other white PVC cap was ajar and emitted another discharge. The PVC caps are not threaded, and they were not attached by a coupler or firmly affixed to the PVC pipes below by anything other than the asphalt surrounding them.

PJmax Thanks a lot, Pete. Appreciate the explanation. I will be talking to the Public Works guy as a starting point.

 

The Public Works guy said get a plumber with a camera on the snake.

 

If your clean out fittings are merely pressed into place and not glued they can pop off if the sewer backs up.

 

The white caps screw into the specially threaded rims of the white cleanout pipe. I do not see how sewage could be spewed 3 feet away without perturbing the water in toilet bowls inside (unless there was a drain line check valve in the house main drain).

The red and black cap preses into the cleanout and tightening the nut in front expands the cap to engage the threads in the rim of the cleanout.